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Sample records for acora garwood classic

  1. 33 CFR 100.913 - ACORA Garwood Classic Offshore Race, Algonac, MI.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... HOMELAND SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.913 ACORA Garwood... stopping at the point of origin. (NAD 83). (b) Special Local Regulations. The regulations of §...

  2. 33 CFR 100.913 - ACORA Garwood Classic Offshore Race, Algonac, MI.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... HOMELAND SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.913 ACORA Garwood... stopping at the point of origin. (NAD 83). (b) Special Local Regulations. The regulations of §...

  3. 33 CFR 100.913 - ACORA Garwood Classic Offshore Race, Algonac, MI.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... shoreline of Harsens Island to north/south line beginning at position 42°37′16″ N, 082°31′11″ W (approx. 500... (approx. 300 ft offshore from the Russell Boat Club), then west along the shoreline of Algonac,...

  4. 33 CFR 100.913 - ACORA Garwood Classic Offshore Race, Algonac, MI.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... waters of St. Clair River's North Channel, Algonac, Michigan, bounded by a north/south line beginning at... to a point of land on Harsens Island (position 42°36′49″ N, 082°33′34″ W) extending east along the shoreline of Harsens Island to north/south line beginning at position 42°37′16″ N, 082°31′11″ W (approx....

  5. 33 CFR 100.913 - ACORA Garwood Classic Offshore Race, Algonac, MI.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... waters of St. Clair River's North Channel, Algonac, Michigan, bounded by a north/south line beginning at... to a point of land on Harsens Island (position 42°36′49″ N, 082°33′34″ W) extending east along the shoreline of Harsens Island to north/south line beginning at position 42°37′16″ N, 082°31′11″ W (approx....

  6. Cold Desert Fluvial Sedimentation and Buried Ice Geology: Garwood Valley (Antarctica) as a Guide to Martian Delta and Gully Geomorphology, Mineralogy, and Biomarker Distribution

    NASA Astrophysics Data System (ADS)

    Levy, J.; Fountain, A. G.; O'Connor, J. E.

    2011-12-01

    The cold, polar desert environmental conditions of the McMurdo Dry Valleys serve as an analog for the physical processes thought to affect Mars. Garwood Valley, one of the McMurdo Dry Valleys (78°S, 164°E) has a mean annual temperature of ~255 K and experiences <50 mm of water-equivalent snowfall per year (most of which sublimates). During the last glacial maximum, the West Antarctic/Ross Ice Sheet ice filled and blocked the lower end of Garwood Valley. Despite surface temperatures ~12 K lower than at present (243 K average), alpine glacier and ice sheet melt in Garwood Valley was sufficient to form a lake in the resulting closed basin, which partly filled with a thick (>8 m) stack of deltaic and lacustrine sediments. In places, the delta sediments overlie remnants of the valley-filling ice plug. The delta sediments are found in a complex composed of three stepped surfaces that suggest sequential lowering of the lake level via incision through the valley-filling ice plug. The delta stratigraphy has been exposed by erosion, driven by massive ice melt and lateral erosion by the modern Garwood River (an alpine glacier-fed river that flows during austral summer). Garwood delta sediments contain LGM-aged algal mats, carbonates, phyllosilicates, and diatomaceous biomarker beds. Fossil algal mats are largely concentrated in delta foreset/topset beds, while carbonate and diatom-bearing layers are common in bottomsets. Mean annual temperatures have remained well below 273 K in Garwood Valley since delta emplacement, resulting in preservation of the lake deposits as ice-cemented permafrost. Where the active layer (summer thawing) intersects massive buried ice deposits, deltaic and glacial drift sediments are mobilized to form gullies, providing modern examples of cold desert gully formation processes in a high-purity ice substrate. These Antarctic conditions are strongly analogous to the climate and hydrological environment anticipated at Holden and Eberswalde craters

  7. Cosmogenic 10Be ages from the Meirs and Garwood Valleys, Denton Hills, West Antarctica, suggest an absence in LGM Ice Sheet expansion.

    NASA Astrophysics Data System (ADS)

    Fink, David; Joy, Kurt; Storey, Bryan

    2014-05-01

    It has been hypothesised that during interglacials, thinning of the Ross Ice Shelf allowed a more open water environment with increased local precipitation. This resulted in outlet glaciers, which drain the Transantarctic Mountains and fed by the East Antarctic Ice Sheet, advancing during moist warmer periods, apparently out of phase with colder arid dry periods. Significantly the ice core record during these warm periods also shows increased accumulation continent wide The geomorphology of the Denton Hills in the Royal Society Range, West Antarctica, is a result of Miocene fluvial incision reworked by subsequent glacial advances throughout the Quaternary. The Garwood and Miers glacial valleys drain ice across the Denton Hills into the Shelf, and should thus show maximum extent during interstadials. To understand the chronology of late Quaternary glaciations, 15 granitic boulders from terminal moraines were sampled for 10Be and 26Al cosmogenic dating. Obtaining reliable exposure ages of erratics within moraines that represent timing of deposition (i.e. glacial advances) is problematic in polar regions, where glacial activity is principally controlled by ice sheet dynamics. Recycling of previously exposed debris, uncertainty in provenance of glacially transported boulders and a lack of a post-depositional hydrologic process to remove previously exposed material from a valley system, leads to ambiguities in multiple exposure ages from a single coeval glacial landform. More importantly, cold-based ice advance can leave a landform unmodified resulting in young erratics deposited on bedrock that shows weathering and/or inconsistent age-altitude relationships. Primarily, inheritance becomes a difficulty in qualifying exposure ages from polar regions. Preliminary results from the Garwood and Miers Valleys indicate that glaciers in the Denton Hills had begun to retreat from their last maximum positions no later than 23-37 ka, and thus the local last glacial maximum

  8. Classics Online.

    ERIC Educational Resources Information Center

    Clayman, Dee L.

    1995-01-01

    Appraises several databases devoted to classical literature. Thesaurus Linguae Graecae (TLG) contains the entire extant corpus of ancient Greek literature, including works on lexicography and historiography, extending into the 15th century. Other works awaiting completion are the Database of Classical Bibliography and a CD-ROM pictorial dictionary…

  9. Classical integrability

    NASA Astrophysics Data System (ADS)

    Torrielli, Alessandro

    2016-08-01

    We review some essential aspects of classically integrable systems. The detailed outline of the sections consists of: 1. Introduction and motivation, with historical remarks; 2. Liouville theorem and action-angle variables, with examples (harmonic oscillator, Kepler problem); 3. Algebraic tools: Lax pairs, monodromy and transfer matrices, classical r-matrices and exchange relations, non-ultralocal Poisson brackets, with examples (non-linear Schrödinger model, principal chiral field); 4. Features of classical r-matrices: Belavin-Drinfeld theorems, analyticity properties, and lift of the classical structures to quantum groups; 5. Classical inverse scattering method to solve integrable differential equations: soliton solutions, spectral properties and the Gel’fand-Levitan-Marchenko equation, with examples (KdV equation, Sine-Gordon model). Prepared for the Durham Young Researchers Integrability School, organised by the GATIS network. This is part of a collection of lecture notes.

  10. Classical Novae

    NASA Astrophysics Data System (ADS)

    Bode, Michael F.; Evans, Aneurin

    2012-07-01

    Preface; 1. Novae - a historical perspective Hilmar W. Duerbeck; 2. Properties of novae: an overview Brian Warner; 3. The evolution of nova-producing binary stars Icko Iben, Jr and Masayuki Y. Fujimoto; 4. Thermonuclear processes S. Starrfield, C. Iliadis and W. R. Hix; 5. Nova atmospheres and winds P. H. Hauschildt; 6. Observational mysteries and theoretical challenges Jordi Jose and Steven N. Shore; 7. Radio emission from novae E. R. Seaquist and M. F. Bode; 8. Infrared studies of classical novae Robert D. Gehrz; 9. Optical and ultraviolet evolution Steven N. Shore; 10. X-ray emission from classical novae in outburst Joachim Krautter; 11. Gamma-rays from classical novae Margarita Hernanz; 12. Resolved nova remnants T. J. O'Brien and M. F. Bode; 13. Dust and molecules in nova environments A. Evans and J. M. C. Rawlings; 14. Extragalactic novae Allen Shafter; Index.

  11. Classical Mechanics

    NASA Astrophysics Data System (ADS)

    Chow, Tai L.

    1995-05-01

    Bring Classical Mechanics To Life With a Realistic Software Simulation! You can enhance the thorough coverage of Chow's Classical Mechanics with a hands-on, real-world experience! John Wiley & Sons, Inc. is proud to announce a new computer simulation for classical mechanics. Developed by the Consortium for Upper-Level Physics Software (CUPS), this simulation offers complex, often realistic calculations of models of various physical systems. Classical Mechanics Simulations (54881-2) is the perfect complement to Chow's text. Like all of the CUPS simulations, it is remarkably easy to use, yet sophisticated enough for explorations of new ideas. Other Important Features Include: * Six powerful simulations include: The Motion Generator, Rotation of Three-Dimensional Objects, Coupled Oscillators, Anharmonic Oscillators, Gravitational Orbits, and Collisions * Pascal source code for all programs is supplied and a number of exercises suggest specific ways the programs can be modified. * Simulations usually include graphical (often animated) displays. The entire CUPS simulation series consists of nine book/software simulations which comprise most of the undergraduate physics major's curriculum.

  12. What classicality? Decoherence and Bohr's classical concepts

    NASA Astrophysics Data System (ADS)

    Schlosshauer, Maximilian; Camilleri, Kristian

    2011-03-01

    Niels Bohr famously insisted on the indispensability of what he termed "classical concepts." In the context of the decoherence program, on the other hand, it has become fashionable to talk about the "dynamical emergence of classicality" from the quantum formalism alone. Does this mean that decoherence challenges Bohr's dictum—for example, that classical concepts do not need to be assumed but can be derived? In this paper we'll try to shed some light down the murky waters where formalism and philosophy cohabitate. To begin, we'll clarify the notion of classicality in the decoherence description. We'll then discuss Bohr's and Heisenberg's take on the quantum—classical problem and reflect on different meanings of the terms "classicality" and "classical concepts" in the writings of Bohr and his followers. This analysis will allow us to put forward some tentative suggestions for how we may better understand the relation between decoherence-induced classicality and Bohr's classical concepts.

  13. The Classical Vacuum.

    ERIC Educational Resources Information Center

    Boyer, Timothy H.

    1985-01-01

    The classical vacuum of physics is not empty, but contains a distinctive pattern of electromagnetic fields. Discovery of the vacuum, thermal spectrum, classical electron theory, zero-point spectrum, and effects of acceleration are discussed. Connection between thermal radiation and the classical vacuum reveals unexpected unity in the laws of…

  14. The Classics Revivified.

    ERIC Educational Resources Information Center

    Matthews, Dorothy, Ed.

    1979-01-01

    The eight articles in this bulletin suggest methods of introducing classical literature into the English curriculum. Article titles are: "Ideas for Teaching Classical Mythology"; "What Novels Should High School Students Read?"; "Enlivening the Classics for Live Students"; "Poetry in Performance: The Value of Song and Oral Interpretation in…

  15. Absolutely classical spin states

    NASA Astrophysics Data System (ADS)

    Bohnet-Waldraff, F.; Giraud, O.; Braun, D.

    2017-01-01

    We introduce the concept of "absolutely classical" spin states, in analogy to absolutely separable states of bipartite quantum systems. Absolutely classical states are states that remain classical (i.e., a convex sum of projectors on coherent states of a spin j ) under any unitary transformation applied to them. We investigate the maximal size of the ball of absolutely classical states centered on the maximally mixed state and derive a lower bound for its radius as a function of the total spin quantum number. We also obtain a numerical estimate of this maximal radius and compare it to the case of absolutely separable states.

  16. Nonzero Classical Discord

    NASA Astrophysics Data System (ADS)

    Gheorghiu, Vlad; de Oliveira, Marcos C.; Sanders, Barry C.

    2015-07-01

    Quantum discord is the quantitative difference between two alternative expressions for bipartite mutual information, given respectively in terms of two distinct definitions for the conditional entropy. By constructing a stochastic model of shared states, classical discord can be similarly defined, quantifying the presence of some stochasticity in the measurement process. Therefore, discord can generally be understood as a quantification of the system's state disturbance due to local measurements, be it quantum or classical. We establish an operational meaning of classical discord in the context of state merging with noisy measurement and thereby show the quantum-classical separation in terms of a negative conditional entropy.

  17. The Classics, Con Brio

    ERIC Educational Resources Information Center

    Hansen, James

    1978-01-01

    Sponsored by a consortium of 30 American universities, Rome's Intercollegiate Center for Classical Studies offers a year of study to American undergraduate classics majors. Instructors are also American and normally stay only a year; teaching assistants are always ex-students of the center. Extensive field trips are an important part of the…

  18. Classic-Ada(TM)

    NASA Technical Reports Server (NTRS)

    Valley, Lois

    1989-01-01

    The SPS product, Classic-Ada, is a software tool that supports object-oriented Ada programming with powerful inheritance and dynamic binding. Object Oriented Design (OOD) is an easy, natural development paradigm, but it is not supported by Ada. Following the DOD Ada mandate, SPS developed Classic-Ada to provide a tool which supports OOD and implements code in Ada. It consists of a design language, a code generator and a toolset. As a design language, Classic-Ada supports the object-oriented principles of information hiding, data abstraction, dynamic binding, and inheritance. It also supports natural reuse and incremental development through inheritance, code factoring, and Ada, Classic-Ada, dynamic binding and static binding in the same program. Only nine new constructs were added to Ada to provide object-oriented design capabilities. The Classic-Ada code generator translates user application code into fully compliant, ready-to-run, standard Ada. The Classic-Ada toolset is fully supported by SPS and consists of an object generator, a builder, a dictionary manager, and a reporter. Demonstrations of Classic-Ada and the Classic-Ada Browser were given at the workshop.

  19. Classical/Non‐classical Polyoxometalate Hybrids

    PubMed Central

    Santiago‐Schübel, Beatrix; Willbold, Sabine; Heß, Volkmar

    2016-01-01

    Abstract Two polyanions [SeI V 2PdII 4WVI 14O56H]11− and [SeI V 4PdII 4WVI 28O108H12]12− are the first hybrid polyoxometalates in which classical (Group 5/6 metal based) and non‐classical (late transition‐metal based) polyoxometalate units are joined. Requiring no supporting groups, this co‐condensation of polyoxotungstate and isopolyoxopalladate constituents also provides a logical link between POM‐PdII coordination complexes and the young subclass of polyoxopalladates. Solid‐state, solution, and gas‐phase studies suggest interesting specific reactivities for these hybrids and point to several potential derivatives and functionalization strategies. PMID:27617918

  20. Classical-Quantum Limits

    NASA Astrophysics Data System (ADS)

    Oliynyk, Todd A.

    2016-12-01

    We introduce a new approach to analyzing the interaction between classical and quantum systems that is based on a limiting procedure applied to multi-particle Schrödinger equations. The limit equations obtained by this procedure, which we refer to as the classical-quantum limit, govern the interaction between classical and quantum systems, and they possess many desirable properties that are inherited in the limit from the multi-particle quantum system. As an application, we use the classical-quantum limit equations to identify the source of the non-local signalling that is known to occur in the classical-quantum hybrid scheme of Hall and Reginatto. We also derive the first order correction to the classical-quantum limit equation to obtain a fully consistent first order approximation to the Schrödinger equation that should be accurate for modeling the interaction between particles of disparate mass in the regime where the particles with the larger masses are effectively classical.

  1. A Classical Science Transformed.

    ERIC Educational Resources Information Center

    Kovalevsky, Jean

    1979-01-01

    Describes how satellites and other tools of space technology have transformed classical geodesy into the science of space geodynamics. The establishment and the activities of the French Center for Geodynamic and Astronomical Research Studies (CERGA) are also included. (HM)

  2. The classical Bloch equations

    NASA Astrophysics Data System (ADS)

    Frimmer, Martin; Novotny, Lukas

    2014-10-01

    Coherent control of a quantum mechanical two-level system is at the heart of magnetic resonance imaging, quantum information processing, and quantum optics. Among the most prominent phenomena in quantum coherent control are Rabi oscillations, Ramsey fringes, and Hahn echoes. We demonstrate that these phenomena can be derived classically by use of a simple coupled-harmonic-oscillator model. The classical problem can be cast in a form that is formally equivalent to the quantum mechanical Bloch equations with the exception that the longitudinal and the transverse relaxation times (T1 and T2) are equal. The classical analysis is intuitive and well suited for familiarizing students with the basic concepts of quantum coherent control, while at the same time highlighting the fundamental differences between classical and quantum theories.

  3. Classical confined particles

    NASA Technical Reports Server (NTRS)

    Horzela, Andrzej; Kapuscik, Edward

    1993-01-01

    An alternative picture of classical many body mechanics is proposed. In this picture particles possess individual kinematics but are deprived from individual dynamics. Dynamics exists only for the many particle system as a whole. The theory is complete and allows to determine the trajectories of each particle. It is proposed to use our picture as a classical prototype for a realistic theory of confined particles.

  4. Randomness: Quantum versus classical

    NASA Astrophysics Data System (ADS)

    Khrennikov, Andrei

    2016-05-01

    Recent tremendous development of quantum information theory has led to a number of quantum technological projects, e.g. quantum random generators. This development had stimulated a new wave of interest in quantum foundations. One of the most intriguing problems of quantum foundations is the elaboration of a consistent and commonly accepted interpretation of a quantum state. Closely related problem is the clarification of the notion of quantum randomness and its interrelation with classical randomness. In this short review, we shall discuss basics of classical theory of randomness (which by itself is very complex and characterized by diversity of approaches) and compare it with irreducible quantum randomness. We also discuss briefly “digital philosophy”, its role in physics (classical and quantum) and its coupling to the information interpretation of quantum mechanics (QM).

  5. Classicism and Romanticism.

    ERIC Educational Resources Information Center

    Huddleston, Gregory H.

    1993-01-01

    Describes one teacher's methods for introducing to secondary English students the concepts of Classicism and Romanticism in relation to pictures of gardens, architecture, music, and literary works. Outlines how the unit leads to a writing assignment based on collected responses over time. (HB)

  6. Classical Mythology. Fourth Edition.

    ERIC Educational Resources Information Center

    Morford, Mark P. O.; Lenardon, Robert J.

    Designed for students with little or no background in classical literature, this book introduces the Greek and Roman myths of creation, myths of the gods, Greek sagas and local legends, and presents contemporary theories about the myths. Drawing on Homer, Hesiod, Pindar, Vergil, and others, the book provides many translations and paraphrases of…

  7. Renewing Literary Classics.

    ERIC Educational Resources Information Center

    Karolides, Nicholas J., Ed.

    1983-01-01

    The articles in this journal issue suggest techniques for classroom use of literature that has "withstood the test of time." The titles of the articles and their authors are as follows: (1) "The Storytelling Connection for the Classics" (Mary Ellen Martin); (2) "Elizabeth Bennet: A Liberated Woman" (Geneva Marking);…

  8. Careers in the Classics

    ERIC Educational Resources Information Center

    Lum, Lydia

    2005-01-01

    America's few Black classics professors have overcome contempt and criticism to contribute a unique perspective to the study of the ancient world. Dr. Patrice Rankine, an associate professor from Purdue University, has grown used to the irony. As one of the few Black classicists teaching at an American university, he has drawn plenty of skepticism…

  9. Classics in What Sense?

    ERIC Educational Resources Information Center

    Camic, Charles

    2008-01-01

    They seem the perfect bookends for the social psychologist's collection of "classics" of the field. Two volumes, nearly identical in shape and weight and exactly a century old in 2008--each professing to usher "social psychology" into the world as they both place the hybrid expression square in their titles but then proceed to stake out the field…

  10. Children's Classics. Fifth Edition.

    ERIC Educational Resources Information Center

    Jordan, Alice M.

    "Children's Classics," a 1947 article by Alice M. Jordan reprinted from "The Horn Book Magazine," examines the dynamics and appeal of some of the most famous books for young readers, including "Alice in Wonderland,""The Wind in the Willows,""Robinson Crusoe," and "Andersen's Fairy Tales." Paul Hein's annotated bibliography, a revision of Jordan's…

  11. Teaching Tomorrow's Classics.

    ERIC Educational Resources Information Center

    Tighe, Mary Ann; Avinger, Charles

    1994-01-01

    Describes young adult novels that may prove to be classics of the genre. Discusses "The "Chocolate War" by Robert Cormier, "The Outsiders" by S. E. Hinton, "The Witch of Blackbird Pond" by Elizabeth George Speare, and "On Fortune's Wheel" by Cynthia Voight. (HB)

  12. Getting into Classical Chinese

    ERIC Educational Resources Information Center

    Kent, George W.

    1976-01-01

    The world of classical Chinese is distant both in time and space from the world of the English-speaking American. The instructor must not, however, use a no-attention-to-meaning approach assuming some words are untranslateable or create confusion in discussing the nature of Chinese script. (CFM)

  13. Observations of classical cepheids

    NASA Technical Reports Server (NTRS)

    Pel, J. W.

    1980-01-01

    The observations of classical Cepheids are reviewed. The main progress that has been made is summarized and some of the problems yet to be solved are discussed. The problems include color excesses, calibration of color, duplicity, ultraviolet colors, temperature-color relations, mass discrepancies, and radius determination.

  14. Classical Demonstration of Polarization.

    ERIC Educational Resources Information Center

    Bauman, Robert P.; Moore, Dennis R.

    1980-01-01

    Presents a classical demonstration of polarization for high school students. The initial state of this model, which demonstrates the important concepts of the optical and quantum problems, was developed during the 1973 summer program on lecture demonstration at the U.S. Naval Academy. (HM)

  15. Classical galactosaemia revisited.

    PubMed

    Bosch, Annet M

    2006-08-01

    Classical galactosaemia (McKusick 230400) is an: autosomal recessive disorder of galactose metabolism, caused by a deficiency of the enzyme galactose-1-phosphate uridyltransferase (GALT; EC 2.7.712). Most patients present in the neonatal period, after ingestion of galactose, with jaundice, hepatosplenomegaly, hepatocellular insufficiency, food intolerance, hypoglycaemia, renal tubular dysfunction, muscle hypotonia, sepsis and cataract. The gold standard for diagnosis of classical galactosaemia is measurement of GALT activity in erythrocytes. Gas-chromatographic determination of urinary sugars and sugar alcohols demonstrates elevated concentrations of galactose and galactitol. The only therapy for patients with classical galactosaemia is a galactose-restricted diet, and initially all galactose must be removed from the diet as soon as the diagnosis is suspected. After the neonatal period, a lactose-free diet is advised in most countries, without restriction of galactose-containing fruit and vegetables. In spite of the strict diet, long-term complications such as retarded mental development, verbal dyspraxia, motor abnormalities and hypergonadotrophic hypogonadism are frequently seen in patients with classical galactosaemia. It has been suggested that these complications may result from endogenous galactose synthesis or from abnormal galactosylation. Novel therapeutic strategies, aiming at the prevention of galactose 1-phosphate production, should be developed. In the meantime, the follow-up protocol for patients with GALT deficiency should focus on early detection, evaluation and, if possible, early intervention in problems of motor, speech and cognitive development.

  16. The classic project

    NASA Astrophysics Data System (ADS)

    Iselin, F. Christoph

    1997-02-01

    Exchange of data and algorithms among accelerator physics programs is difficult because of unnecessary differences in input formats and internal data structures. To alleviate these problems a C++ class library called CLASSIC (Class Library for Accelerator System Simulation and Control) is being developed with the goal to provide standard building blocks for computer programs used in accelerator design. It includes modules for building accelerator lattice structures in computer memory using a standard input language, a graphical user interface, or a programmed algorithm. It also provides simulation algorithms. These can easily be replaced by modules which communicate with the control system of the accelerator. Exchange of both data and algorithm between different programs using the CLASSIC library should present no difficulty.

  17. Classical swine fever.

    PubMed

    Moennig, V; Becher, P; Beer, M

    2013-01-01

    Classical swine fever is a serious and economically important transboundary disease threatening pig production globally. The infection may occur in backyard pigs, feral pig populations and domestic pigs. Whereas there are proven control strategies for the latter pig population, control in backyard pigs with poor biosecurity settings or in wild boar populations of high density still poses a problem in some parts of the world. Laboratory diagnostic methods, efficacious vaccines and contingency plans are in place in most industrialised countries. So far modified live vaccines (MLV) are still the first choice for rapid and reliable immune protection. Since antibodies elicited by conventional MLV cannot be distinguished from antibodies after natural infection, considerable efforts are put into the development of a live marker vaccine accompanied by a serological test. Nevertheless, some remaining gaps with respect to the diagnosis of and vaccination against classical swine fever have been identified.

  18. Classical Vs. Superfluid Turbulence

    NASA Astrophysics Data System (ADS)

    Roche, P.-E.

    2008-11-01

    Thanks to a zero-viscosity, superfluids offer a unique testing ground for hydrodynamic models, in particular for turbulence ones. In Kolmogorov's turbulence model, viscosity is well known to damp the kinetic energy of the smallest eddies, and thus to introduce a cut-off at one end of the turbulent cascade. Significant differences between this ``classical'' turbulence and the turbulence of a superfluid are therefore expected, but --surprisingly- most experiments rather evidenced strong similarities. We will give an overview of a set of experiments designed to compare in details the classical versus superfluid turbulences, up to a record mass flow of superfluid (700g/s of He @ 1.6K). Then, we will focus on some unexpected vorticity measurements, which can be interpreted assuming that the superfluid vortices are passively advected by the largest scales of the flow, in contrast with the ``classical'' turbulence counterpart. Numerical simulations -based on regular DNS- will be presented to complete this interpretation. In collaboration with C. Barenghi, University of Newcastle; B. Castaing and E. Levèque, ENSL, Lyon; S. David, IEF, CNRS, Orsay; B. Rousset, SBT/CEA, Grenoble; and P. Tabeling, H. Willaime MMN, ESPCI, Paris.

  19. Entanglement with classical fields

    SciTech Connect

    Lee, K.F.; Thomas, J.E.

    2004-05-01

    We experimentally demonstrate a simple classical-field optical heterodyne method which employs postselection to reproduce the polarization correlations of a four-particle entangled state. We give a heuristic argument relating this method to the measurement of multiple quantum fields by correlated homodyne detection. We suggest that using multiple classical fields and postselection, one can reproduce the polarization correlations obtained in quantum experiments which employ multiple single-photon sources and linear optics to prepare multiparticle entangled states. Our experimental scheme produces four spatially separated beams which are separately detected by mixing with four independent optical local oscillators (LO) of variable polarization. Analog multiplication of the four beat signals enables projection onto a four-particle polarization-state basis. Appropriate band pass filtering is used to produce a signal proportional to the projections of the maximally entangled four-field polarization state, H{sub 1})H{sub 2})H{sub 3})H{sub 4})+V{sub 1})V{sub 2})V{sub 3})V{sub 4}), onto the product of the four LO polarizations. Since the data from multiple observers is combined prior to postselection, this method does not constitute a test of nonlocality. However, we reproduce the polarization correlations of the 32 elements in the truth table from the quantum mechanical Greenberger-Horne-Zeilinger experiments on the violation of local realism. We also demonstrate a form of classical entanglement swapping in a four-particle basis.

  20. Semi-classical Electrodynamics

    NASA Astrophysics Data System (ADS)

    Lestone, John

    2016-03-01

    Quantum electrodynamics is complex and its associated mathematics can appear overwhelming for those not trained in this field. We describe semi-classical approaches that can be used to obtain a more intuitive physical feel for several QED processes including electro-statics, Compton scattering, pair annihilation, the anomalous magnetic moment, and the Lamb shift, that could be taught easily to undergraduate students. Any physicist who brings their laptop to the talk will be able to build spread sheets in less than 10 minutes to calculate g/2 =1.001160 and a Lamb shift of 1057 MHz.

  1. Fano Interference in Classical Oscillators

    ERIC Educational Resources Information Center

    Satpathy, S.; Roy, A.; Mohapatra, A.

    2012-01-01

    We seek to illustrate Fano interference in a classical coupled oscillator by using classical analogues of the atom-laser interaction. We present an analogy between the dressed state picture of coherent atom-laser interaction and a classical coupled oscillator. The Autler-Townes splitting due to the atom-laser interaction is analogous to the…

  2. Classical Trajectories and Quantum Spectra

    NASA Technical Reports Server (NTRS)

    Mielnik, Bogdan; Reyes, Marco A.

    1996-01-01

    A classical model of the Schrodinger's wave packet is considered. The problem of finding the energy levels corresponds to a classical manipulation game. It leads to an approximate but non-perturbative method of finding the eigenvalues, exploring the bifurcations of classical trajectories. The role of squeezing turns out decisive in the generation of the discrete spectra.

  3. Perspective: Quantum or classical coherence?

    PubMed

    Miller, William H

    2012-06-07

    Some coherence effects in chemical dynamics are described correctly by classical mechanics, while others only appear in a quantum treatment--and when these are observed experimentally it is not always immediately obvious whether their origin is classical or quantum. Semiclassical theory provides a systematic way of adding quantum coherence to classical molecular dynamics and thus provides a useful way to distinguish between classical and quantum coherence. Several examples are discussed which illustrate both cases. Particularly interesting is the situation with electronically non-adiabatic processes, where sometimes whether the coherence effects are classical or quantum depends on what specific aspects of the process are observed.

  4. Supersymmetry in classical mechanics

    NASA Astrophysics Data System (ADS)

    Suen, W. M.; Wong, C. W.; Young, K.

    2000-06-01

    The concept of supersymmetry extended to classical mechanics relates one-parameter families of Hamiltonians H( ξ, x, p)= p2+ V( ξ, x), such that the mapping from the phase space of H( ξ1, x, p) to that of H( ξ2, x, p) preserves time-evolution and conserves total energy; as a result, equal-energy periodic orbits in the two have the same period. While t-evolution is a contact transformation generated by H, ξ-evolution is a generalized contact transformation generated by a function K, and preserves phase volume except for a point sink (source) as ξ increases (decreases). Closed-form solutions of ξ-evolution include several well-known examples.

  5. The classical vacuum

    NASA Astrophysics Data System (ADS)

    Boyer, T. H.

    1985-08-01

    The history of vacuum concepts is reviewed, noting that no way is known to physically produce a true void. Even at absolute zero, a pattern of electromagnetic wave fluctuations are still present. The fluctuations are called zero-point radiation (ZPR). To be invariant to Lorentz transformation, ZPR has a spectral intensity proportional to the cube of each frequency. ZPR does not change in response to compression and produces a force between objects that is inversely proportional to the 4th power of the separation distance. The ZPR scale value has been measured to be one-half of the Planck constant, and is the measure of the energy of a harmonic oscillator, such as the electron, in a vacuum. Finally, since gravitational accelerations always occur in the physical space, a minimum thermal radiation can also be found for the vacuum, implying that a fixed relationship exists between thermal radiation and the classical vacuum.

  6. Supersymmetric classical cosmology

    SciTech Connect

    Escamilla-Rivera, Celia; Obregón, Octavio; Ureña-López, L. Arturo E-mail: octavio@fisica.ugto.mx

    2010-12-01

    In this work a supersymmetric cosmological model is analyzed in which we consider a general superfield action of a homogeneous scalar field supermultiplet interacting with the scale factor in a supersymmetric FRW model. There appear fermionic superpartners associated with both the scale factor and the scalar field, and classical equations of motion are obtained from the super-Wheeler-DeWitt equation through the usual WKB method. The resulting supersymmetric Einstein-Klein-Gordon equations contain extra radiation and stiff matter terms, and we study their solutions in flat space for different scalar field potentials. The solutions are compared to the standard case, in particular those corresponding to the exponential potential, and their implications for the dynamics of the early Universe are discussed in turn.

  7. Classical and quantum ghosts

    NASA Astrophysics Data System (ADS)

    Sbisà, Fulvio

    2015-01-01

    The aim of these notes is to provide a self-contained review of why it is generically a problem when a solution of a theory possesses ghost fields among the perturbation modes. We define what a ghost field is and we show that its presence is associated with a classical instability whenever the ghost field interacts with standard fields. We then show that the instability is more severe at quantum level, and that perturbative ghosts can exist only in low energy effective theories. However, if we do not consider very ad hoc choices, compatibility with observational constraints implies that low energy effective ghosts can exist only at the price of giving up Lorentz invariance or locality above the cut-off, in which case the cut-off has to be much lower that the energy scales we currently probe in particle colliders. We also comment on the possible role of extra degrees of freedom which break Lorentz invariance spontaneously.

  8. Grassmannization of classical models

    NASA Astrophysics Data System (ADS)

    Pollet, Lode; Kiselev, Mikhail N.; Prokof'ev, Nikolay V.; Svistunov, Boris V.

    2016-11-01

    Applying Feynman diagrammatics to non-fermionic strongly correlated models with local constraints might seem generically impossible for two separate reasons: (i) the necessity to have a Gaussian (non-interacting) limit on top of which the perturbative diagrammatic expansion is generated by Wick’s theorem, and (ii) Dyson’s collapse argument implying that the expansion in powers of coupling constant is divergent. We show that for arbitrary classical lattice models both problems can be solved/circumvented by reformulating the high-temperature expansion (more generally, any discrete representation of the model) in terms of Grassmann integrals. Discrete variables residing on either links, plaquettes, or sites of the lattice are associated with the Grassmann variables in such a way that the partition function (as well as all correlation functions) of the original system and its Grassmann-field counterpart are identical. The expansion of the latter around its Gaussian point generates Feynman diagrams. Our work paves the way for studying lattice gauge theories by treating bosonic and fermionic degrees of freedom on equal footing.

  9. Extended symmetrical classical electrodynamics.

    PubMed

    Fedorov, A V; Kalashnikov, E G

    2008-03-01

    In this paper, we discuss a modification of classical electrodynamics in which "ordinary" point charges are absent. The modified equations contain additional terms describing the induced charges and currents. The densities of the induced charges and currents depend on the vector k and the vectors of the electromagnetic field, E and B . It is shown that the vectors E and B can be defined in terms of two four-potentials and the components of k are the components of a four-tensor of the third rank. The Lagrangian of the modified electrodynamics is defined. The conditions are derived at which only one four-potential determines the behavior of the electromagnetic field. It is also shown that static modified electrodynamics can describe the electromagnetic field in the inner region of an electric monopole. In the outer region of the electric monopole the electric field is governed by the Maxwell equations. It follows from boundary conditions at the interface between the inner and outer regions of the monopole that the vector k has a discrete spectrum. The electric and magnetic fields, energy, and angular momentum of the monopole are found for different eigenvalues of k .

  10. Innovation: the classic traps.

    PubMed

    Kanter, Rosabeth Moss

    2006-11-01

    Never a fad, but always in or out of fashion, innovation gets rediscovered as a growth enabler every half dozen years. Too often, though, grand declarations about innovation are followed by mediocre execution that produces anemic results, and innovation groups are quietly disbanded in cost-cutting drives. Each managerial generation embarks on the same enthusiastic quest for the next new thing. And each generation faces the same vexing challenges- most of which stem from the tensions between protecting existing revenue streams critical to current success and supporting new concepts that may be crucial to future success. In this article, Harvard Business School professor Rosabeth Moss Kanter reflects on the four major waves of innovation enthusiasm she's observed over the past 25 years. She describes the classic mistakes companies make in innovation strategy, process, structure, and skills assessment, illustrating her points with a plethora of real-world examples--including AT&T Worldnet, Timberland, and Ocean Spray. A typical strategic blunder is when managers set their hurdles too high or limit the scope of their innovation efforts. Quaker Oats, for instance, was so busy in the 1990s making minor tweaks to its product formulas that it missed larger opportunities in distribution. A common process mistake is when managers strangle innovation efforts with the same rigid planning, budgeting, and reviewing approaches they use in their existing businesses--thereby discouraging people from adapting as circumstances warrant. Companies must be careful how they structure fledgling entities alongside existing ones, Kanter says, to avoid a clash of cultures and agendas--which Arrow Electronics experienced in its attempts to create an online venture. Finally, companies commonly undervalue and underinvest in the human side of innovation--for instance, promoting individuals out of innovation teams long before their efforts can pay off. Kanter offers practical advice for avoiding

  11. A Classic Beauty

    NASA Technical Reports Server (NTRS)

    2007-01-01

    M51, whose name comes from being the 51st entry in Charles Messier's catalog, is considered to be one of the classic examples of a spiral galaxy. At a distance of about 30 million light-years from Earth, it is also one of the brightest spirals in the night sky. A composite image of M51, also known as the Whirlpool Galaxy, shows the majesty of its structure in a dramatic new way through several of NASA's orbiting observatories. X-ray data from NASA's Chandra X-ray Observatory reveals point-like sources (purple) that are black holes and neutron stars in binary star systems. Chandra also detects a diffuse glow of hot gas that permeates the space between the stars. Optical data from the Hubble Space Telescope (green) and infrared emission from the Spitzer Space Telescope (red) both highlight long lanes in the spiral arms that consist of stars and gas laced with dust. A view of M51 with the Galaxy Evolution Explorer telescope shows hot, young stars that produce lots of ultraviolet energy (blue).

    The textbook spiral structure is thought be the result of an interaction M51 is experiencing with its close galactic neighbor, NGC 5195, which is seen just above. Some simulations suggest M51's sharp spiral shape was partially caused when NGC 5195 passed through its main disk about 500 million years ago. This gravitational tug of war may also have triggered an increased level of star formation in M51. The companion galaxy's pull would be inducing extra starbirth by compressing gas, jump-starting the process by which stars form.

  12. Dynamical Symmetries in Classical Mechanics

    ERIC Educational Resources Information Center

    Boozer, A. D.

    2012-01-01

    We show how symmetries of a classical dynamical system can be described in terms of operators that act on the state space for the system. We illustrate our results by considering a number of possible symmetries that a classical dynamical system might have, and for each symmetry we give examples of dynamical systems that do and do not possess that…

  13. Operator Formulation of Classical Mechanics.

    ERIC Educational Resources Information Center

    Cohn, Jack

    1980-01-01

    Discusses the construction of an operator formulation of classical mechanics which is directly concerned with wave packets in configuration space and is more similar to that of convential quantum theory than other extant operator formulations of classical mechanics. (Author/HM)

  14. Teaching and Demonstrating Classical Conditioning.

    ERIC Educational Resources Information Center

    Sparrow, John; Fernald, Peter

    1989-01-01

    Discusses classroom demonstrations of classical conditioning and notes tendencies to misrepresent Pavlov's procedures. Describes the design and construction of the conditioner that is used for demonstrating classical conditioning. Relates how students experience conditioning, generalization, extinction, discrimination, and spontaneous recovery.…

  15. Quantum reduplication of classical solitons

    NASA Astrophysics Data System (ADS)

    Sveshnikov, Konstantin

    1993-09-01

    The possible existence of a series of quantum copies of classical soliton solutions is discussed, which do not exist when the effective Planck constant of the theory γ tends to zero. Within the conventional weak-coupling expansion in √ γ such non-classical solitons are O(√ γ) in energy and therefore lie in between the true classical solutions and elementary quantum excitations. Analytic results concerning the shape functions, masses and characteristic scales of such quantum excitations are given for soliton models of a self-interacting scalar field. Stability properties and quantization of fluctuations in the neighborhood of these configurations are also discussed in detail.

  16. Classical and quantum Malus laws

    NASA Astrophysics Data System (ADS)

    Wódkiewicz, Krzysztof

    1995-04-01

    The classical and the quantum Malus laws for light and spin are discussed. It is shown that for spin 1/2, the quantum Malus law is equivalent in form to the classical Malus law provided the statistical average involves a quasidistribution function that can become negative. A generalization of Malus's law for arbitrary spin s is obtained in the form of a Feynman path-integral representation for the Malus amplitude. The classical limit of the Malus amplitude for s-->∞ is discussed.

  17. Quantum localization of classical mechanics

    NASA Astrophysics Data System (ADS)

    Batalin, Igor A.; Lavrov, Peter M.

    2016-07-01

    Quantum localization of classical mechanics within the BRST-BFV and BV (or field-antifield) quantization methods are studied. It is shown that a special choice of gauge fixing functions (or BRST-BFV charge) together with the unitary limit leads to Hamiltonian localization in the path integral of the BRST-BFV formalism. In turn, we find that a special choice of gauge fixing functions being proportional to extremals of an initial non-degenerate classical action together with a very special solution of the classical master equation result in Lagrangian localization in the partition function of the BV formalism.

  18. Experimental contextuality in classical light

    PubMed Central

    Li, Tao; Zeng, Qiang; Song, Xinbing; Zhang, Xiangdong

    2017-01-01

    The Klyachko, Can, Binicioglu, and Shumovsky (KCBS) inequality is an important contextuality inequality in three-level system, which has been demonstrated experimentally by using quantum states. Using the path and polarization degrees of freedom of classical optics fields, we have constructed the classical trit (cetrit), tested the KCBS inequality and its geometrical form (Wright’s inequality) in this work. The projection measurement has been implemented, the clear violations of the KCBS inequality and its geometrical form have been observed. This means that the contextuality inequality, which is commonly used in test of the conflict between quantum theory and noncontextual realism, may be used as a quantitative tool in classical optical coherence to describe correlation characteristics of the classical fields. PMID:28291227

  19. Classical Foundations: Leah Rochel Johnson

    ERIC Educational Resources Information Center

    Lum, Lydia

    2005-01-01

    This article discusses the accomplishments of Leah Rochel Johnson, Assistant Professor of Classics and Ancient Mediterranean Studies and History, Pennsylvania State University. It provides insight into her values and beliefs and testimony from those who work most closely with her.

  20. Experimental contextuality in classical light

    NASA Astrophysics Data System (ADS)

    Li, Tao; Zeng, Qiang; Song, Xinbing; Zhang, Xiangdong

    2017-03-01

    The Klyachko, Can, Binicioglu, and Shumovsky (KCBS) inequality is an important contextuality inequality in three-level system, which has been demonstrated experimentally by using quantum states. Using the path and polarization degrees of freedom of classical optics fields, we have constructed the classical trit (cetrit), tested the KCBS inequality and its geometrical form (Wright’s inequality) in this work. The projection measurement has been implemented, the clear violations of the KCBS inequality and its geometrical form have been observed. This means that the contextuality inequality, which is commonly used in test of the conflict between quantum theory and noncontextual realism, may be used as a quantitative tool in classical optical coherence to describe correlation characteristics of the classical fields.

  1. Quantum money with classical verification

    SciTech Connect

    Gavinsky, Dmitry

    2014-12-04

    We propose and construct a quantum money scheme that allows verification through classical communication with a bank. This is the first demonstration that a secure quantum money scheme exists that does not require quantum communication for coin verification. Our scheme is secure against adaptive adversaries - this property is not directly related to the possibility of classical verification, nevertheless none of the earlier quantum money constructions is known to possess it.

  2. New Perspective on Classical Electromagnetism

    DTIC Science & Technology

    2013-04-01

    R. Feynman , R. Leighton, and M. Sands, The Feynman Lectures in Physics vol II (Addison-Wesley, Reading, MA, 1964). 6. W.K.H. Panofsky and M...of the basics of classical electromagnetism is provided by recognizing a previously overlooked law of induction as well as the physical reality of the...classical electromagnetism is provided by recognizing a previously overlooked law of induction as well as the physical reality of the vector potential

  3. Classical theory of radiating strings

    NASA Technical Reports Server (NTRS)

    Copeland, Edmund J.; Haws, D.; Hindmarsh, M.

    1990-01-01

    The divergent part of the self force of a radiating string coupled to gravity, an antisymmetric tensor and a dilaton in four dimensions are calculated to first order in classical perturbation theory. While this divergence can be absorbed into a renormalization of the string tension, demanding that both it and the divergence in the energy momentum tensor vanish forces the string to have the couplings of compactified N = 1 D = 10 supergravity. In effect, supersymmetry cures the classical infinities.

  4. Quantum money with classical verification

    NASA Astrophysics Data System (ADS)

    Gavinsky, Dmitry

    2014-12-01

    We propose and construct a quantum money scheme that allows verification through classical communication with a bank. This is the first demonstration that a secure quantum money scheme exists that does not require quantum communication for coin verification. Our scheme is secure against adaptive adversaries - this property is not directly related to the possibility of classical verification, nevertheless none of the earlier quantum money constructions is known to possess it.

  5. Classical approach in atomic physics

    NASA Astrophysics Data System (ADS)

    Solov'ev, E. A.

    2011-12-01

    The application of a classical approach to various quantum problems - the secular perturbation approach to quantization of a hydrogen atom in external fields and a helium atom, the adiabatic switching method for calculation of a semiclassical spectrum of a hydrogen atom in crossed electric and magnetic fields, a spontaneous decay of excited states of a hydrogen atom, Gutzwiller's approach to Stark problem, long-lived excited states of a helium atom discovered with the help of Poincaré section, inelastic transitions in slow and fast electron-atom and ion-atom collisions - is reviewed. Further, a classical representation in quantum theory is discussed. In this representation the quantum states are treated as an ensemble of classical states. This approach opens the way to an accurate description of the initial and final states in classical trajectory Monte Carlo (CTMC) method and a purely classical explanation of tunneling phenomenon. The general aspects of the structure of the semiclassical series such as renormgroup symmetry, criterion of accuracy and so on are reviewed as well.

  6. Hermeneutic reading of classic texts.

    PubMed

    Koskinen, Camilla A-L; Lindström, Unni Å

    2013-09-01

    The purpose of this article is to broaden the understandinfg of the hermeneutic reading of classic texts. The aim is to show how the choice of a specific scientific tradition in conjunction with a methodological approach creates the foundation that clarifies the actual realization of the reading. This hermeneutic reading of classic texts is inspired by Gadamer's notion that it is the researcher's own research tradition and a clearly formulated theoretical fundamental order that shape the researcher's attitude towards texts and create the starting point that guides all reading, uncovering and interpretation. The researcher's ethical position originates in a will to openness towards what is different in the text and which constantly sets the researcher's preunderstanding and research tradition in movement. It is the researcher's attitude towards the text that allows the text to address, touch and arouse wonder. Through a flexible, lingering and repeated reading of classic texts, what is different emerges with a timeless value. The reading of classic texts is an act that may rediscover and create understanding for essential dimensions and of human beings' reality on a deeper level. The hermeneutic reading of classic texts thus brings to light constantly new possibilities of uncovering for a new envisioning and interpretation for a new understanding of the essential concepts and phenomena within caring science.

  7. Quantum remnants in the classical limit

    NASA Astrophysics Data System (ADS)

    Kowalski, A. M.; Plastino, A.

    2016-09-01

    We analyze here the common features of two dynamical regimes: a quantum and a classical one. We deal with a well known semi-classic system in its route towards the classical limit, together with its purely classic counterpart. We wish to ascertain i) whether some quantum remnants can be found in the classical limit and ii) the details of the quantum-classic transition. The so-called mutual information is the appropriate quantifier for this task. Additionally, we study the Bandt-Pompe's symbolic patterns that characterize dynamical time series (representative of the semi-classical system under scrutiny) in their evolution towards the classical limit.

  8. Classical anomalies for spinning particles

    NASA Astrophysics Data System (ADS)

    Gamboa, Jorge; Plyushchay, Mikhail

    1998-02-01

    We discuss the phenomenon of classical anomaly. It is observed for 3D Berezin-Marinov (BM), Barducci-Casalbuoni-Lusanna (BCL) and Cortés-Plyushchay-Velázquez (CPV) pseudoclassical spin particle models. We show that quantum mechanically these different models correspond to the same P, T-invariant system of planar fermions, but the quantum system has global symmetries being not reproducible classically in full in any of the models. We demonstrate that the specific U(1) gauge symmetry characterized by the opposite coupling constants of spin s = + {1}/{2} and s = - {1}/{2} states has a natural classical analog in the CPV model but can be reproduced in the BM and BCL models in an obscure and rather artificial form. We also show that the BM and BCL models quantum mechanically are equivalent in any odd-dimensional space-time, but describe different quantum systems in even space-time dimensions.

  9. From classical to quantum criticality

    NASA Astrophysics Data System (ADS)

    Podolsky, Daniel; Shimshoni, Efrat; Silvi, Pietro; Montangero, Simone; Calarco, Tommaso; Morigi, Giovanna; Fishman, Shmuel

    2014-06-01

    We study the crossover from classical to quantum phase transitions at zero temperature within the framework of ϕ4 theory. The classical transition at zero temperature can be described by the Landau theory, turning into a quantum Ising transition with the addition of quantum fluctuations. We perform a calculation of the transition line in the regime where the quantum fluctuations are weak. The calculation is based on a renormalization group analysis of the crossover between classical and quantum transitions, and is well controlled even for space-time dimensionality D below 4. In particular, for D =2 we obtain an analytic expression for the transition line which is valid for a wide range of parameters, as confirmed by numerical calculations based on the density matrix renormalization group. This behavior could be tested by measuring the phase diagram of the linear-zigzag instability in systems of trapped ions or repulsively interacting dipoles.

  10. Entropy concepts in classical electrodynamics

    NASA Astrophysics Data System (ADS)

    Cole, Daniel C.

    2002-11-01

    Aspects of entropy and related thermodynamic analyses are discussed here that have been deduced in recent years in the area of classical electrodynamics. A motivating factor for most of this work has been an attempted theory of nature often called, "stochastic electrodynamics" (SED). This theory involves classical electrodynamics (Maxwell's equations plus the relativistic version of Newton's second law of motion for particles), but with the consideration that motion and fluctuations should not necessarily be assumed to reduce to zero at temperature T = 0. Both fairly subtle and rather blatant assumptions were often imposed in early thermodynamic analyses of electrodynamic systems that prevented the analyses from being sufficiently general to account for these "zero-point" properties, which hindered classical physics from being able to better account for quantum mechanical phenomena observed in nature. In turn, such thermodynamic considerations have helped motivate many of the key ideas of SED.

  11. Optimum Onager: The Classical Mechanics of a Classical Siege Engine

    ERIC Educational Resources Information Center

    Denny, Mark

    2009-01-01

    The onager is a throwing weapon of classical antiquity, familiar to both the ancient Greeks and Romans. Here we analyze the dynamics of onager operation and derive the optimum angle for launching a projectile to its maximum range. There is plenty of scope for further considerations about increasing onager range, and so by thinking about how this…

  12. Overview of Classical Swine Fever (Hog Cholera, Classical Swine fever)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Classical swine fever is a contagious often fatal disease of pigs clinically characterized by high body temperature, lethargy, yellowish diarrhea, vomits and purple skin discoloration of ears, lower abdomen and legs. It was first described in the early 19th century in the USA. Later, a condition i...

  13. Quantum teleportation without classical channel

    NASA Astrophysics Data System (ADS)

    Al Amri, M.; Li, Zheng-Hong; Zubairy, M. Suhail

    2016-11-01

    For the first time, we show how quantum teleportation can be achieved without the assistance of classical channels. Our protocol does not need any pre-established entangled photon pairs beforehand. Just by utilizing quantum Zeno effect and couterfactual communication idea, we can achieve two goals; entangling a photon and an atom and also disentangling them by non-local interaction. Information is completely transferred from atom to photon with controllable disentanglement processes. More importantly, there is no need to confirm teleportation results via classical channels.

  14. Classical three-box 'paradox'

    NASA Astrophysics Data System (ADS)

    Kirkpatrick, K. A.

    2003-05-01

    A simple classical probabilistic system (a simple card game) classically exemplifies Aharonov and Vaidman's 'three-box 'paradox'' (1991 J. Phys. A: Math. Gen. 24 2315), implying that the three-box example is neither quantal nor a paradox and leaving one with less difficulty to busy the interpreters of quantum mechanics. An ambiguity in the usual expression of the retrodiction formula is shown to have misled Albert et al (1985 Phys. Rev. Lett. 54 5) to a result not, in fact, 'curious'; the discussion illustrates how to avoid this ambiguity.

  15. Comparing classical and quantum equilibration

    NASA Astrophysics Data System (ADS)

    Malabarba, Artur S. L.; Farrelly, Terry; Short, Anthony J.

    2016-09-01

    By using a physically relevant and theory independent definition of measurement-based equilibration, we show quantitatively that equilibration is easier for quantum systems than for classical systems, in the situation where the initial state of the system is completely known (a pure state). This shows that quantum equilibration is a fundamental aspect of many quantum systems, while classical equilibration relies on experimental ignorance. When the state is not completely known (a mixed state), this framework also shows that quantum equilibration requires weaker conditions.

  16. Classical Music as Enforced Utopia

    ERIC Educational Resources Information Center

    Leech-Wilkinson, Daniel

    2016-01-01

    In classical music composition, whatever thematic or harmonic conflicts may be engineered along the way, everything always turns out for the best. Similar utopian thinking underlies performance: performers see their job as faithfully carrying out their master's (the composer's) wishes. The more perfectly they represent them, the happier the…

  17. Classical and molecular genetic mapping

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A brief history of classical genetic mapping in soybean [Glycine max (L.) Merr.] is described. Detailed descriptions are given of the development of molecular genetic linkage maps based upon various types of DNA markers Like many plant and animal species, the first molecular map of soybean was bas...

  18. Classics in Reading: A Survey.

    ERIC Educational Resources Information Center

    Froese, Victor

    1982-01-01

    Frank Smith and Kenneth Goodman were the most frequently cited authors; Bond and Dykstra's "The Cooperative Research Program in First Grade Reading Instruction" and Chall's "Learning to Read: The Great Debate" the most frequently cited works in a survey that asked graduate faculty in reading to name "classics" in reading research. (FL)

  19. Teaching Classical Mechanics Using Smartphones

    ERIC Educational Resources Information Center

    Chevrier, Joel; Madani, Laya; Ledenmat, Simon; Bsiesy, Ahmad

    2013-01-01

    A number of articles published in this column have dealt with topics in classical mechanics. This note describes some additional examples employing a smartphone and the new software iMecaProf. Steve Jobs presented the iPhone as "perfect for gaming." Thanks to its microsensors connected in real time to the numerical world, physics…

  20. Classical simulation of entangled states

    NASA Astrophysics Data System (ADS)

    Bharath, H. M.; Ravishankar, V.

    2014-06-01

    Characterization of nonclassicality or quantumness of a state is fundamental to foundations of quantum mechanics and quantum information. At the heart of the problem is the question whether there exist classical systems—howsoever complicated—that can mimic a given quantum state. Whilst this has been traditionally addressed through the violation of Bell inequality or nonseparability, we show that it is possible to go beyond them, by introducing the concept of classical simulation. Focusing on the two-qubit case, we show that, while for pure states, classical simulability is equivalent to existence of a local hidden variable (LHV) model, the conditions for simulability can be weaker for mixed states, demanding what we call only a generalized LHV description. Consequently, quantum states which defy a classical simulation—which we call exceptional—may require conditions which are more stringent than violation of Bell inequalities. We illustrate these features with a number of representative examples and discuss the underlying reasons, by employing fairly simple arguments.

  1. Relative Clauses in Classical Nahuatl

    ERIC Educational Resources Information Center

    Langacker, Ronald W.

    1975-01-01

    Jane Rosenthal's paper on relative clauses in Classical Nahuatl is discussed, and it is argued that she misses an important generalization. An alternative analysis to a class of relative pronouns and new rules for the distribution of relative pronouns are proposed. (SC)

  2. Vowel intelligibility in classical singing.

    PubMed

    Gregg, Jean Westerman; Scherer, Ronald C

    2006-06-01

    Vowel intelligibility during singing is an important aspect of communication during performance. The intelligibility of isolated vowels sung by Western classically trained singers has been found to be relatively low, in fact, decreasing as pitch rises, and it is lower for women than for men. The lack of contextual cues significantly deteriorates vowel intelligibility. It was postulated in this study that the reduced intelligibility of isolated sung vowels may be partly from the vowels used by the singers in their daily vocalises. More specifically, if classically trained singers sang only a few American English vowels during their vocalises, their intelligibility for American English vowels would be less than for those classically trained singers who usually vocalize on most American English vowels. In this study, there were 21 subjects (15 women, 6 men), all Western classically trained performers as well as teachers of classical singing. They sang 11 words containing 11 different American English vowels, singing on two pitches a musical fifth apart. Subjects were divided into two groups, those who normally vocalize on 4, 5, or 6 vowels, and those who sing all 11 vowels during their daily vocalises. The sung words were cropped to isolate the vowels, and listening tapes were created. Two listening groups, four singing teachers and five speech-language pathologists, were asked to identify the vowels intended by the singers. Results suggest that singing fewer vowels during daily vocalises does not decrease intelligibility compared with singing the 11 American English vowels. Also, in general, vowel intelligibility was lower with the higher pitch, and vowels sung by the women were less intelligible than those sung by the men. Identification accuracy was about the same for the singing teacher listeners and the speech-language pathologist listeners except for the lower pitch, where the singing teachers were more accurate.

  3. No return to classical reality

    NASA Astrophysics Data System (ADS)

    Jennings, David; Leifer, Matthew

    2016-01-01

    At a fundamental level, the classical picture of the world is dead, and has been dead now for almost a century. Pinning down exactly which quantum phenomena are responsible for this has proved to be a tricky and controversial question, but a lot of progress has been made in the past few decades. We now have a range of precise statements showing that whatever the ultimate laws of nature are, they cannot be classical. In this article, we review results on the fundamental phenomena of quantum theory that cannot be understood in classical terms. We proceed by first granting quite a broad notion of classicality, describe a range of quantum phenomena (such as randomness, discreteness, the indistinguishability of states, measurement-uncertainty, measurement-disturbance, complementarity, non-commutativity, interference, the no-cloning theorem and the collapse of the wave-packet) that do fall under its liberal scope, and then finally describe some aspects of quantum physics that can never admit a classical understanding - the intrinsically quantum mechanical aspects of nature. The most famous of these is Bell's theorem, but we also review two more recent results in this area. Firstly, Hardy's theorem shows that even a finite-dimensional quantum system must contain an infinite amount of information, and secondly, the Pusey-Barrett-Rudolph theorem shows that the wave function must be an objective property of an individual quantum system. Besides being of foundational interest, results of this sort now find surprising practical applications in areas such as quantum information science and the simulation of quantum systems.

  4. Classical Analog to Entanglement Reversibility

    NASA Astrophysics Data System (ADS)

    Chitambar, Eric; Fortescue, Ben; Hsieh, Min-Hsiu

    2015-08-01

    In this Letter we study the problem of secrecy reversibility. This asks when two honest parties can distill secret bits from some tripartite distribution pX Y Z and transform secret bits back into pX Y Z at equal rates using local operation and public communication. This is the classical analog to the well-studied problem of reversibly concentrating and diluting entanglement in a quantum state. We identify the structure of distributions possessing reversible secrecy when one of the honest parties holds a binary distribution, and it is possible that all reversible distributions have this form. These distributions are more general than what is obtained by simply constructing a classical analog to the family of quantum states known to have reversible entanglement. An indispensable tool used in our analysis is a conditional form of the Gács-Körner common information.

  5. Invariants from classical field theory

    SciTech Connect

    Diaz, Rafael; Leal, Lorenzo

    2008-06-15

    We introduce a method that generates invariant functions from perturbative classical field theories depending on external parameters. By applying our methods to several field theories such as Abelian BF, Chern-Simons, and two-dimensional Yang-Mills theory, we obtain, respectively, the linking number for embedded submanifolds in compact varieties, the Gauss' and the second Milnor's invariant for links in S{sup 3}, and invariants under area-preserving diffeomorphisms for configurations of immersed planar curves.

  6. Classical photometry of prefractal surfaces.

    PubMed

    Shkuratov, Yuriy; Petrov, Dmitriy; Videen, Gorden

    2003-11-01

    Using the scale invariance of classical photometry, we develop an approach to finding the photometric function of prefractal structures that form a random topography. The photometric function of the prefractal surfaces is found as the general solution of the resulting differential equation in partial derivatives. The function depends on two parameters: the number of hierarchical levels of the prefractal structures and the roughness parameter of the single-level generation. As a limiting case, the approach includes our previous theory that considered fractoids.

  7. Psoriasis: classical and emerging comorbidities*

    PubMed Central

    de Oliveira, Maria de Fátima Santos Paim; Rocha, Bruno de Oliveira; Duarte, Gleison Vieira

    2015-01-01

    Psoriasis is a chronic inflammatory systemic disease. Evidence shows an association of psoriasis with arthritis, depression, inflammatory bowel disease and cardiovascular diseases. Recently, several other comorbid conditions have been proposed as related to the chronic inflammatory status of psoriasis. The understanding of these conditions and their treatments will certainly lead to better management of the disease. The present article aims to synthesize the knowledge in the literature about the classical and emerging comorbidities related to psoriasis. PMID:25672294

  8. Quantum to classical randomness extractors

    NASA Astrophysics Data System (ADS)

    Wehner, Stephanie; Berta, Mario; Fawzi, Omar

    2013-03-01

    The goal of randomness extraction is to distill (almost) perfect randomness from a weak source of randomness. When the source yields a classical string X, many extractor constructions are known. Yet, when considering a physical randomness source, X is itself ultimately the result of a measurement on an underlying quantum system. When characterizing the power of a source to supply randomness it is hence a natural question to ask, how much classical randomness we can extract from a quantum system. To tackle this question we here introduce the notion of quantum-to-classical randomness extractors (QC-extractors). We identify an entropic quantity that determines exactly how much randomness can be obtained. Furthermore, we provide constructions of QC-extractors based on measurements in a full set of mutually unbiased bases (MUBs), and certain single qubit measurements. As the first application, we show that any QC-extractor gives rise to entropic uncertainty relations with respect to quantum side information. Such relations were previously only known for two measurements. As the second application, we resolve the central open question in the noisy-storage model [Wehner et al., PRL 100, 220502 (2008)] by linking security to the quantum capacity of the adversary's storage device.

  9. Optimum Onager: The Classical Mechanics of a Classical Siege Engine

    NASA Astrophysics Data System (ADS)

    Denny, Mark

    2009-12-01

    The onager is a throwing weapon of classical antiquity, familiar to both the ancient Greeks and Romans. Here we analyze the dynamics of onager operation and derive the optimum angle for launching a projectile to its maximum range. There is plenty of scope for further considerations about increasing onager range, and so by thinking about how this machine might be improved, a student can gain insight beyond the equations of motion and can test hypotheses on readily available working models. Some of these performance improvements are considered in this paper.

  10. Classical Optics and its Applications

    NASA Astrophysics Data System (ADS)

    Mansuripur, Masud

    2009-02-01

    Preface; Introduction; 1. Abbe's sine condition; 2. Fourier optics; 3. Effect of polarization on diffraction in systems of high numerical aperture; 4. Gaussian beam optics; 5. Coherent and incoherent imaging; 6. First-order temporal coherence in classical optics; 7. The Van Cittert-Zernike theorem; 8. Partial polarization, Stokes parameters, and the Poincarè Sphere; 9. Second-order coherence and the Hanbury Brown - Twiss experiment; 10. What in the world are surface plasmons?; 11. Surface plasmon polaritons on metallic surfaces; 12. The Faraday effecy; 13. The magneto-optical Kerr effect; 14. The Sagnac interferometer; 15. Fabry-Perot etalons in polarized light; 16. The Ewald-Oseen extinction theorem; 17. Reciprocity in classical Linear optics; 18. Optical pulse compression; 19. The uncertainty principle in classical optics; 20. Omni-directional dielectric mirrors; 21. Optical vortices; 22. Geometric-optical rays, Poynting's vector, and field momenta; 23. Doppler shift, stellar aberration, and convection of light by moving Media; 24. Diffraction gratings; 25. Diffractive optical elements; 26. The talbot effect; 27. Some quirks of total internal reflection; 28. Evanescent coupling; 29. Internal and external conical refraction; 30. Transmission of light through small elliptical apertures; 31. The method of Fox and Li; 32. The beam propagation method; 33. Launching light into a Fiber; 34. The optics of demiconductor fiode Laser; 35. Michelson's dtellar interferometer; 36. Bracewell's interferometric telescope; 37. Scanning optical microscopy; 38. Zernike's method of phase contrast; 39. Polarization microscopy; 40. Nomarski's differential interference contrast microscope; 41. The Van Leeuwenhoek microscope; 42. Projection photolithography; 43. Interaction of light with subwavelength structures; 44 The Ronchi test; 45. The Shack-Hartmann Wavefront sensor; 46. Ellipsometry; 47. Holography and holographic interferometry; 48. Self-focusing in non-linear optical media; 49

  11. Classical analog of quantum phase

    SciTech Connect

    Ord, G.N.

    1992-07-01

    A modified version of the Feynman relativistic chessboard model (FCM) is investigated in which the paths involved are spirals in the space-time. Portions of the paths in which the particle`s proper time is reversed are interpreted in terms of antiparticles. With this intepretation the particle-antiparticle field produced by such trajectories provides a classical analog of the phase associated with particle paths in the unmodified FCM. It is shwon that in the nonrelativistic limit the resulting kernel is the correct Dirac propagator and that particle-antiparticle symmetry is in this case responsible for quantum interference. 7 refs., 3 figs.

  12. Superadditivity of classical capacity revisited

    SciTech Connect

    Pilyavets, Oleg V.; Karpov, Evgueni A.; Schäfer, Joachim

    2014-12-04

    We introduce new type of superadditivity for classical capacity of quantum channels, which involves the properties of channels’ environment. By imposing different restrictions on the total energy contained in channels’ environment we can consider different types of superadditivity. Using lossy bosonic and additive noise quantum channels as examples, we demonstrate that their capacities can be either additive or superadditive depending on the values of channels parameters. The parameters corresponding to transition between the additive and superadditive cases are related with recently found critical and supercritical parameters for Gaussian channels.

  13. Classical dynamics on Snyder spacetime

    NASA Astrophysics Data System (ADS)

    Mignemi, S.

    2015-04-01

    We study the classical dynamics of a particle in Snyder spacetime, adopting the formalism of constrained Hamiltonian systems introduced by Dirac. We show that the motion of a particle in a scalar potential is deformed with respect to special relativity by terms of order βE2. A remarkable result is that in the relativistic Snyder model a consistent choice of the time variable must necessarily depend on the dynamics. This is a consequence of the nontrivial mixing between position and momentum coordinates intrinsic to the Snyder model.

  14. Classics in Chemical Neuroscience: Haloperidol.

    PubMed

    Tyler, Marshall W; Zaldivar-Diez, Josefa; Haggarty, Stephen J

    2017-02-15

    The discovery of haloperidol catalyzed a breakthrough in our understanding of the biochemical basis of schizophrenia, improved the treatment of psychosis, and facilitated deinstitutionalization. In doing so, it solidified the role for chemical neuroscience as a means to elucidate the molecular underpinnings of complex neuropsychiatric disorders. In this Review, we will cover aspects of haloperidol's synthesis, manufacturing, metabolism, pharmacology, approved and off-label indications, and adverse effects. We will also convey the fascinating history of this classic molecule and the influence that it has had on the evolution of neuropsychopharmacology and neuroscience.

  15. Physiological characteristics of classical ballet.

    PubMed

    Schantz, P G; Astrand, P O

    1984-10-01

    The aerobic and anaerobic energy yield during professional training sessions ("classes") of classical ballet as well as during rehearsed and performed ballets has been studied by means of oxygen uptake, heart rate, and blood lactate concentration determinations on professional ballet dancers from the Royal Swedish Ballet in Stockholm. The measured oxygen uptake during six different normal classes at the theatre averaged about 35-45% of the maximal oxygen uptake, and the blood lactate concentration averaged 3 mM (N = 6). During 10 different solo parts of choreographed dance (median length = 1.8 min) representative for moderately to very strenuous dance, an average oxygen uptake (measured during the last minute) of 80% of maximum and blood lactate concentration of 10 mM was measured (N = 10). In addition, heart rate registrations from soloists in different ballets during performance and final rehearsals frequently indicated a high oxygen uptake relative to maximum and an average blood lactate concentration of 11 mM (N = 5). Maximal oxygen uptake, determined in 1971 (N = 11) and 1983 (N = 13) in two different groups of dancers, amounted to on the average 51 and 56 ml X min-1 X kg-1 for the females and males, respectively. In conclusion, classical ballet is a predominantly intermittent type of exercise. In choreographed dance each exercise period usually lasts only a few minutes, but can be very demanding energetically, while during the dancers' basic training sessions, the energy yield is low.

  16. Overuse injuries in classical ballet.

    PubMed

    Khan, K; Brown, J; Way, S; Vass, N; Crichton, K; Alexander, R; Baxter, A; Butler, M; Wark, J

    1995-05-01

    Successful management of classical ballet dancers with overuse injuries requires an understanding of the art form, precise knowledge of anatomy and awareness of certain conditions. Turnout is the single most fundamental physical attribute in classical ballet and 'forcing turnout' frequently contributes to overuse injuries. Common presenting conditions arising from the foot and ankle include problems at the first metatarsophalangeal joint, second metatarsal stress fractures, flexor hallucis longus tendinitis and anterior and posterior ankle impingement syndromes. Persistent shin pain in dancers is often due to chronic compartment syndrome, stress fracture of the posteromedial or anterior tibia. Knee pain can arise from patellofemoral syndrome, patellar tendon insertional pathologies, or a combination of both. Hip and back problems are also prevalent in dancers. To speed injury recovery of dancers, it is important for the sports medicine team to cooperate fully. This permits the dancer to benefit from accurate diagnosis, technique correction where necessary, the full range of manual therapies to joint and soft tissue, appropriate strengthening programmes and maintenance of dance fitness during any time out of class with Pilates-based exercises and nutrition advice. Most overuse ballet conditions respond well to a combination of conservative therapies. Those dancers that do require surgical management still depend heavily on ballet-specific rehabilitation for a complete recovery.

  17. Teaching classical mechanics using smartphones

    NASA Astrophysics Data System (ADS)

    Chevrier, Joel; Madani, Laya; Ledenmat, Simon; Bsiesy, Ahmad

    2013-09-01

    A number of articles published in this column have dealt with topics in classical mechanics. This note describes some additional examples employing a smartphone and the new software iMecaProf.4 Steve Jobs presented the iPhone as "perfect for gaming."5 Thanks to its microsensors connected in real time to the numerical world, physics teachers could add that smartphones are "perfect for teaching science." The software iMecaProf displays in real time the measured data on a screen. The visual representation is built upon the formalism of classical mechanics. iMecaProf receives data 100 times a second from iPhone sensors through a Wi-Fi connection using the application Sensor Data.6 Data are the three components of the acceleration vector in the smartphone frame and smartphone's orientation through three angles (yaw, pitch, and roll). For circular motion (uniform or not), iMecaProf uses independent measurements of the rotation angle θ, the angular speed dθ/dt, and the angular acceleration d2θ/dt2.

  18. Friedreich Ataxia in Classical Galactosaemia.

    PubMed

    Neville, Siobhán; O'Sullivan, Siobhan; Sweeney, Bronagh; Lynch, Bryan; Hanrahan, Donncha; Knerr, Ina; Lynch, Sally Ann; Crushell, Ellen

    2016-01-01

    Movement disorders such as ataxia are a recognized complication of classical galactosaemia, even in diet-compliant patients. Here, we report the coexistence of classical galactosaemia and Friedreich ataxia (FRDA) in nine children from seven Irish Traveller families. These two autosomal recessive disorders, the loci for which are located on either side of the centromere of chromosome 9, appear to be in linkage disequilibrium in this subgroup. Both conditions are known to occur with increased frequency amongst the Irish Traveller population.Each member of our cohort had been diagnosed with galactosaemia in the neonatal period, and all are homozygous for the common Q188R mutation in the GALT gene. Eight of the nine patients later presented with progressive ataxia, between the ages of 5-13 years. Another child presented in cardiac failure secondary to dilated cardiomyopathy at 7 years of age. He was not ataxic at presentation and, one year from diagnosis, his neurological examination remains normal. The diagnosis of FRDA was confirmed by detecting the common pathogenic GAA expansion in both alleles of the frataxin gene (FXN) in each patient.Neurological symptoms are easily attributed to an underlying diagnosis of galactosaemia. It is important to consider a diagnosis of Friedreich ataxia in a child from the Irish Traveller population with galactosaemia who presents with ataxia or cardiomyopathy.

  19. Classically spinning and isospinning solitons

    NASA Astrophysics Data System (ADS)

    Battye, Richard A.; Haberichter, Mareike

    2012-09-01

    We investigate classically spinning topological solitons in (2+1)- and (3+1)-dimensional models; more explicitely spinning sigma model solitons in 2+1 dimensions and Skyrme solitons in 2+1 and 3+1 dimensions. For example, such types of solitons can be used to describe quasiparticle excitations in ferromagnetic quantum Hall systems or to model spin and isospin states of nuclei. The standard way to obtain solitons with quantised spin and isospin is the semiclassical quantization procedure: One parametrizes the zero-mode space - the space of energy-degenerate soliton configurations generated from a single soliton by spatial translations and rotations in space and isospace - by collective coordinates which are then taken to be time-dependent. This gives rise to additional dynamical terms in the Hamiltonian which can then be quantized following semiclassical quantization rules. A simplification which is often made in the literature is to apply a simple adiabatic approximation to the (iso)rotational zero modes of the soliton by assuming that the soliton's shape is rotational frequency independent. Our numerical results on classically spinning arbitrarily deforming soliton solutions clearly show that soliton deformation cannot be ignored.

  20. Diminuendo: Classical Music and the Academy

    ERIC Educational Resources Information Center

    Asia, Daniel

    2010-01-01

    How is the tradition of Western classical music faring on university campuses? Before answering this question, it is necessary to understand what has transpired with classical music in the wider culture, as the relationship between the two is so strong. In this article, the author discusses how classical music has taken a big cultural hit in…

  1. Africa in Classical Antiquity: A Curriculum Resource

    ERIC Educational Resources Information Center

    Masciantonio, Rudolph

    1977-01-01

    A curriculum resource developed by the School District of Philadelphia deals with Africa in Classical Antiquity. Each unit contains suggestions for lower, middle and upper schools. Topics covered are: history of Africa; great Africans in the Graeco-Roman world; racial attitudes; blacks in classical art, and Africa in classical literature. (CHK)

  2. Africa in Classical Antiquity: A Curriculum Resource.

    ERIC Educational Resources Information Center

    Masciantonio, Rudolph; And Others

    This curriculum resource is intended primarily to assist teachers of Latin and Greek to infuse material on Africa in classical antiquity into the curriculum at all levels. It gathers together background information on the role of Africa in classical antiquity that has not been treated in traditional classical language courses. The resource guide…

  3. Reexamining the Quantum-Classical Relation

    NASA Astrophysics Data System (ADS)

    Bokulich, Alisa

    2008-10-01

    1. Intertheoretic relations: are imperialism and isolationism our only options?; 2. Heisenberg's closed theories and pluralistic realism; 3. Dirac's open theories and the reciprocal correspondence principle; 4. Bohr's generalization of classical mechanics; 5. Semiclassical mechanics: putting quantum flesh on classical bones; 6. Can classical structures explain quantum phenomena?; 7. A structural approach to intertheoretic relations; References; Index.

  4. Introducing the Classics to Reluctant Readers.

    ERIC Educational Resources Information Center

    Lazarus, Lissa J.

    Using the pocket classics can be a painless way to introduce the classics to eighth-grade students. Condensed versions of the classics can take the sting out of the reading, stimulate students' interest, and help prepare them for high school. To offer students in one eighth-grade class some control over their own learning, a contract system was…

  5. Un-renormalized classical electromagnetism

    SciTech Connect

    Ibison, Michael . E-mail: ibison@earthtech.org

    2006-02-15

    This paper follows in the tradition of direct-action versions of electromagnetism having the aim of avoiding a balance of infinities wherein a mechanical mass offsets an infinite electromagnetic mass so as to arrive at a finite observed value. However, the direct-action approach ultimately failed in that respect because its initial exclusion of self-action was later found to be untenable in the relativistic domain. Pursing the same end, this paper examines instead a version of electromagnetism wherein mechanical action is excluded and self-action is retained. It is shown that the resulting theory is effectively interacting due to the presence of infinite forces. A vehicle for the investigation is a pair of classical point charges in a positronium-like arrangement for which the orbits are found to be self-sustaining and naturally quantized.

  6. DOE Fundamentals Handbook: Classical Physics

    SciTech Connect

    Not Available

    1992-06-01

    The Classical Physics Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of physical forces and their properties. The handbook includes information on the units used to measure physical properties; vectors, and how they are used to show the net effect of various forces; Newton's Laws of motion, and how to use these laws in force and motion applications; and the concepts of energy, work, and power, and how to measure and calculate the energy involved in various applications. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility systems and equipment.

  7. Classical mechanics of nonconservative systems.

    PubMed

    Galley, Chad R

    2013-04-26

    Hamilton's principle of stationary action lies at the foundation of theoretical physics and is applied in many other disciplines from pure mathematics to economics. Despite its utility, Hamilton's principle has a subtle pitfall that often goes unnoticed in physics: it is formulated as a boundary value problem in time but is used to derive equations of motion that are solved with initial data. This subtlety can have undesirable effects. I present a formulation of Hamilton's principle that is compatible with initial value problems. Remarkably, this leads to a natural formulation for the Lagrangian and Hamiltonian dynamics of generic nonconservative systems, thereby filling a long-standing gap in classical mechanics. Thus, dissipative effects, for example, can be studied with new tools that may have applications in a variety of disciplines. The new formalism is demonstrated by two examples of nonconservative systems: an object moving in a fluid with viscous drag forces and a harmonic oscillator coupled to a dissipative environment.

  8. Classically Stable Nonsingular Cosmological Bounces

    NASA Astrophysics Data System (ADS)

    Ijjas, Anna; Steinhardt, Paul J.

    2016-09-01

    One of the fundamental questions of theoretical cosmology is whether the Universe can undergo a nonsingular bounce, i.e., smoothly transit from a period of contraction to a period of expansion through violation of the null energy condition (NEC) at energies well below the Planck scale and at finite values of the scale factor such that the entire evolution remains classical. A common claim has been that a nonsingular bounce either leads to ghost or gradient instabilities or a cosmological singularity. In this Letter, we consider a well-motivated class of theories based on the cubic Galileon action and present a procedure for explicitly constructing examples of a nonsingular cosmological bounce without encountering any pathologies and maintaining a subluminal sound speed for comoving curvature modes throughout the NEC violating phase. We also discuss the relation between our procedure and earlier work.

  9. Classically Stable Nonsingular Cosmological Bounces.

    PubMed

    Ijjas, Anna; Steinhardt, Paul J

    2016-09-16

    One of the fundamental questions of theoretical cosmology is whether the Universe can undergo a nonsingular bounce, i.e., smoothly transit from a period of contraction to a period of expansion through violation of the null energy condition (NEC) at energies well below the Planck scale and at finite values of the scale factor such that the entire evolution remains classical. A common claim has been that a nonsingular bounce either leads to ghost or gradient instabilities or a cosmological singularity. In this Letter, we consider a well-motivated class of theories based on the cubic Galileon action and present a procedure for explicitly constructing examples of a nonsingular cosmological bounce without encountering any pathologies and maintaining a subluminal sound speed for comoving curvature modes throughout the NEC violating phase. We also discuss the relation between our procedure and earlier work.

  10. Classical Cosmology Through Animation Stories

    NASA Astrophysics Data System (ADS)

    Mijic, Milan; Kang, E. Y. E.; Longson, T.; State LA SciVi Project, Cal

    2010-05-01

    Computer animations are a powerful tool for explanation and communication of ideas, especially to a younger generation. Our team completed a three part sequence of short, computer animated stories about the insight and discoveries that lead to the understanding of the overall structure of the universe. Our principal characters are Immanuel Kant, Henrietta Leavitt, and Edwin Hubble. We utilized animations to model and visualize the physical concepts behind each discovery and to recreate the characters, locations, and flavor of the time. The animations vary in length from 6 to 11 minutes. The instructors or presenters may wish to utilize them separately or together. The animations may be used for learning classical cosmology in a visual way in GE astronomy courses, in pre-college science classes, or in public science education setting.

  11. Gamma Rays from Classical Novae

    NASA Technical Reports Server (NTRS)

    1997-01-01

    NASA at the University of Chicago, provided support for a program of theoretical research into the nature of the thermonuclear outbursts of the classical novae and their implications for gamma ray astronomy. In particular, problems which have been addressed include the role of convection in the earliest stages of nova runaway, the influence of opacity on the characteristics of novae, and the nucleosynthesis expected to accompany nova outbursts on massive Oxygen-Neon-Magnesium (ONeMg) white dwarfs. In the following report, I will identify several critical projects on which considerable progress has been achieved and provide brief summaries of the results obtained:(1) two dimensional simulation of nova runaway; (2) nucleosynthesis of nova modeling; and (3) a quasi-analytic study of nucleosynthesis in ONeMg novae.

  12. GALK inhibitors for classic galactosemia.

    PubMed

    Lai, Kent; Boxer, Matthew B; Marabotti, Anna

    2014-06-01

    Classic galactosemia is an inherited metabolic disease for which, at present, no therapy is available apart from galactose-restricted diet. However, the efficacy of the diet is questionable, since it is not able to prevent the insurgence of chronic complications later in life. In addition, it is possible that dietary restriction itself could induce negative side effects. Therefore, there is a need for an alternative therapeutic approach that can avert the manifestation of chronic complications in the patients. In this review, the authors describe the development of a novel class of pharmaceutical agents that target the production of a toxic metabolite, galactose-1-phosphate, considered as the main culprit for the cause of the complications, in the patients.

  13. Gastrointestinal Health in Classic Galactosemia.

    PubMed

    Shaw, Kelly A; Mulle, Jennifer G; Epstein, Michael P; Fridovich-Keil, Judith L

    2016-07-01

    Classic galactosemia (CG) is an autosomal recessive disorder of galactose metabolism that affects approximately 1/50,000 live births in the USA. Following exposure to milk, which contains large quantities of galactose, affected infants may become seriously ill. Early identification by newborn screening with immediate dietary galactose restriction minimizes or prevents the potentially lethal acute symptoms of CG. However, more than half of individuals with CG still experience long-term complications including cognitive disability, behavioral problems, and speech impairment. Anecdotal reports have also suggested frequent gastrointestinal (GI) problems, but this outcome has not been systematically addressed. In this study we explored the prevalence of GI symptoms among 183 children and adults with CG (cases) and 190 controls. Cases reported 4.5 times more frequent constipation (95% CI 1.8-11.5) and 4.2 times more frequent nausea (95% CI 1.2-15.5) than controls. Cases with genotypes predicting residual GALT activity reported less frequent constipation than cases without predicted GALT activity but this difference was not statistically significant. Because the rigor of dietary galactose restriction varies among individuals with galactosemia, we further tested whether GI symptoms associated with diet in infancy. Though constipation was almost four times as common among cases reporting a more restrictive diet in infancy, this difference was not statistically significant. These data confirm that certain GI symptoms are more common in classic galactosemia compared to controls and suggest that future studies should investigate associations with residual GALT activity and dietary galactose restriction in early life.

  14. Classical vs. non-classical pathways of mineral formation (Invited)

    NASA Astrophysics Data System (ADS)

    De Yoreo, J. J.

    2013-12-01

    Recent chemical analyses, microscopy studies and computer simulations suggest many minerals nucleate through aggregation of pre-nucleation clusters and grow by particle-mediated processes that involve amorphous or disordered precursors. Still other analyses, both experimental and computational, conclude that even simple mineral systems like calcium carbonate form via a barrier-free process of liquid-liquid separation, which is followed by dehydration of the ion-rich phase to form the solid products. However, careful measurements of calcite nucleation rates on a variety of ionized surfaces give results that are in complete agreement with the expectations of classical nucleation theory, in which clusters growing through ion-by-ion addition overcome a free energy barrier through the natural microscopic density fluctuations of the system. Here the challenge of integrating these seemingly disparate observations and analyses into a coherent picture of mineral formation is addressed by considering the energy barriers to calcite formation predicted by the classical theory and the changes in those barriers brought about by the introduction of interfaces and clusters, both stable and metastable. Results from a suite of in situ TEM, AFM, and optical experiments combined with simulations are used to illustrate the conclusions. The analyses show that the expected barrier to homogeneous calcite nucleation is prohibitive even at concentrations exceeding the solubility limit of amorphous calcium carbonate. However, as demonstrated by experiments on self-assembled monolayers, the introduction of surfaces that moderately decrease the interfacial energy associated with the forming nucleus can reduce the magnitude of the barrier to a level that is easily surmounted under typical laboratory conditions. In the absence of such surfaces, experiments that proceed by continually increasing supersaturation with time can easily by-pass direct nucleation of calcite and open up pathways through

  15. Open questions in classical gravity

    SciTech Connect

    Mannheim, P.D. )

    1994-04-01

    In this work, the authors discuss some outstanding open questions regarding the validity and uniqueness of the standard second-order Newton-Einstein classical gravitational theory. On the observational side the authors discuss the degree to which the realm of validity of Newton's law of gravity can actually be extended to distances much larger than the solar system distance scales on which the law was originally established. On the theoretical side the authors identify some commonly accepted (but actually still open to question) assumptions which go into the formulation of the standard second-order Einstein theory in the first place. In particular, it is shown that while the familiar second-order Poisson gravitational equation (and accordingly its second-order covariant Einstein generalization) may be sufficient to yield Newton's law of gravity they are not in fact necessary. The standard theory thus still awaits the identification of some principle which would then make it necessary too. It is shown that current observational information does not exclusively mandate the standard theory, and that the conformal invariant fourth-order theory of gravity considered recently by Mannheim and Kazanas is also able to meet the constraints of data, and in fact to do so without the need for any so far unobserved nonluminous or dark matter. 37 refs., 7 figs.

  16. Relaxation properties in classical diamagnetism

    NASA Astrophysics Data System (ADS)

    Carati, A.; Benfenati, F.; Galgani, L.

    2011-06-01

    It is an old result of Bohr that, according to classical statistical mechanics, at equilibrium a system of electrons in a static magnetic field presents no magnetization. Thus a magnetization can occur only in an out of equilibrium state, such as that produced through the Foucault currents when a magnetic field is switched on. It was suggested by Bohr that, after the establishment of such a nonequilibrium state, the system of electrons would quickly relax back to equilibrium. In the present paper, we study numerically the relaxation to equilibrium in a modified Bohr model, which is mathematically equivalent to a billiard with obstacles, immersed in a magnetic field that is adiabatically switched on. We show that it is not guaranteed that equilibrium is attained within the typical time scales of microscopic dynamics. Depending on the values of the parameters, one has a relaxation either to equilibrium or to a diamagnetic (presumably metastable) state. The analogy with the relaxation properties in the Fermi Pasta Ulam problem is also pointed out.

  17. Pembrolizumab in classical Hodgkin's lymphoma.

    PubMed

    Maly, Joseph; Alinari, Lapo

    2016-09-01

    Pembrolizumab is a humanized monoclonal antibody directed against programmed cell death protein 1 (PD-1), a key immune-inhibitory molecule expressed on T cells and implicated in CD4+ T-cell exhaustion and tumor immune-escape mechanisms. Classical Hodgkin's lymphoma (cHL) is a unique B-cell malignancy in the sense that malignant Reed-Sternberg (RS) cells represent a small percentage of cells within an extensive immune cell infiltrate. PD-1 ligands are upregulated on RS cells as a consequence of both chromosome 9p24.1 amplification and Epstein-Barr virus infection and by interacting with PD-1 promote an immune-suppressive effect. By augmenting antitumor immune response, pembrolizumab and nivolumab, another monoclonal antibody against PD-1, have shown significant activity in patients with relapsed/refractory cHL as well as an acceptable toxicity profile with immune-related adverse events that are generally manageable. In this review, we explore the rationale for targeting PD-1 in cHL, review the clinical trial results supporting the use of checkpoint inhibitors in this disease, and present future directions for investigation in which this approach may be used.

  18. Ordering in classical Coulombic systems.

    SciTech Connect

    Schiffer, J. P.

    1998-01-22

    The author discusses the properties of classical Coulombic matter at low temperatures. It has been well known for some time [1,2] that infinite Coulombic matter will crystallize in body-centered cubic form when the quantity {Lambda} (the dimensionless ratio of the average two-particle Coulomb energy to the kinetic energy per particle) is larger than {approximately}175. But the systems of such particles that have been produced in the laboratory in ion traps, or ion beams, are finite with surfaces defined by the boundary conditions that have to be satisfied. This results in ion clouds with sharply defined curved surfaces, and interior structures that show up as a set of concentric layers that are parallel to the outer surface. The ordering does not appear to be cubic, but the charges on each shell exhibit a ''hexatic'' pattern of equilateral triangles that is the characteristic of liquid crystals. The curvature of the surfaces prevents the structures on successive shells from interlocking in any simple fashion. This class of structures was first found in simulations [3] and later in experiments [4].

  19. Structure of classical affine and classical affine fractional W-algebras

    SciTech Connect

    Suh, Uhi Rinn

    2015-01-15

    We introduce a classical BRST complex (See Definition 3.2.) and show that one can construct a classical affine W-algebra via the complex. This definition clarifies that classical affine W-algebras can be considered as quasi-classical limits of quantum affine W-algebras. We also give a definition of a classical affine fractional W-algebra as a Poisson vertex algebra. As in the classical affine case, a classical affine fractional W-algebra has two compatible λ-brackets and is isomorphic to an algebra of differential polynomials as a differential algebra. When a classical affine fractional W-algebra is associated to a minimal nilpotent, we describe explicit forms of free generators and compute λ-brackets between them. Provided some assumptions on a classical affine fractional W-algebra, we find an infinite sequence of integrable systems related to the algebra, using the generalized Drinfel’d and Sokolov reduction.

  20. Classical underpinnings of gravitationally induced quantum interference

    SciTech Connect

    Mannheim, P.D.

    1998-02-01

    We show that the gravitational modification of the phase of a neutron beam [the Colella-Overhauser-Werner (COW) experiment] has a classical origin, being due to the time delay that classical particles experience in traversing a background gravitational field. Similarly, we show that classical light waves also undergo a phase shift in traversing a gravitational field. We show that the COW experiment respects the equivalence principle even in the presence of quantum mechanics. {copyright} {ital 1998} {ital The American Physical Society}

  1. Diagrammar in classical scalar field theory

    SciTech Connect

    Cattaruzza, E.; Gozzi, E.; Francisco Neto, A.

    2011-09-15

    In this paper we analyze perturbatively a g{phi}{sup 4}classical field theory with and without temperature. In order to do that, we make use of a path-integral approach developed some time ago for classical theories. It turns out that the diagrams appearing at the classical level are many more than at the quantum level due to the presence of extra auxiliary fields in the classical formalism. We shall show that a universal supersymmetry present in the classical path-integral mentioned above is responsible for the cancelation of various diagrams. The same supersymmetry allows the introduction of super-fields and super-diagrams which considerably simplify the calculations and make the classical perturbative calculations almost 'identical' formally to the quantum ones. Using the super-diagrams technique, we develop the classical perturbation theory up to third order. We conclude the paper with a perturbative check of the fluctuation-dissipation theorem. - Highlights: > We provide the Feynman diagrams of perturbation theory for a classical field theory. > We give a super-formalism which links the quantum diagrams to the classical ones. > We check perturbatively the fluctuation-dissipation theorem.

  2. Classical teleportation of a quantum Bit

    PubMed

    Cerf; Gisin; Massar

    2000-03-13

    Classical teleportation is defined as a scenario where the sender is given the classical description of an arbitrary quantum state while the receiver simulates any measurement on it. This scenario is shown to be achievable by transmitting only a few classical bits if the sender and receiver initially share local hidden variables. Specifically, a communication of 2.19 bits is sufficient on average for the classical teleportation of a qubit, when restricted to von Neumann measurements. The generalization to positive-operator-valued measurements is also discussed.

  3. Classical Solution Thermodynamics: A Retrospective View.

    ERIC Educational Resources Information Center

    Van Ness, H. C.; Abbott, M. M.

    1985-01-01

    Examines topics related to classical solution thermodynamics, considering energy, enthalpy, and the Gibbs function. Applicable mathematical equations are introduced and discussed when appropriate. (JN)

  4. Primitive Ontology and the Classical World

    NASA Astrophysics Data System (ADS)

    Allori, Valia

    In this chapter, I present the common structure of quantum theories with a primitive ontology (PO), and discuss in what sense the classical world emerges from quantum theories as understood in this framework. In addition, I argue that the PO approach is better at analyzing the classical limit than the rival wave function ontology approach or any other approach in which the classical world is non-reductively "emergent:" even if the classical limit within this framework needs to be fully developed, the difficulties are technical rather than conceptual, while this is not true for the alternatives.

  5. Classical and semiclassical aspects of chemical dynamics

    SciTech Connect

    Gray, S.K.

    1982-08-01

    Tunneling in the unimolecular reactions H/sub 2/C/sub 2/ ..-->.. HC/sub 2/H, HNC ..-->.. HCN, and H/sub 2/CO ..-->.. H/sub 2/ + CO is studied with a classical Hamiltonian that allows the reaction coordinate and transverse vibrational modes to be considered directly. A combination of classical perturbation theory and the semiclassical WKB method allows tunneling probabilities to be obtained, and a statistical theory (RRKM) is used to construct rate constants for these reactions in the tunneling regime. In this fashion, it is found that tunneling may be important, particularly for low excitation energies. Nonadiabatic charge transfer in the reaction Na + I ..-->.. Na /sup +/ + I/sup -/ is treated with classical trajectories based on a classical Hamiltonian that is the analogue of a quantum matrix representation. The charge transfer cross section obtained is found to agree reasonably well with the exact quantum results. An approximate semiclassical formula, valid at high energies, is also obtained. The interaction of radiation and matter is treated from a classical viewpoint. The excitation of an HF molecule in a strong laser is described with classical trajectories. Quantum mechanical results are also obtained and compared to the classical results. Although the detailed structure of the pulse time averaged energy absorption cannot be reproduced classically, classical mechanics does predict the correct magnitude of energy absorption, as well as certain other qualitative features. The classical behavior of a nonrotating diatomic molecule in a strong laser field is considered further, by generating a period advance map that allows the solution over many periods of oscillation of the laser to be obtained with relative ease. Classical states are found to form beautiful spirals in phase space as time progresses. A simple pendulum model is found to describe the major qualitative features. (WHM)

  6. Why/How Does Classics Matter?

    ERIC Educational Resources Information Center

    Cartledge, Paul

    2005-01-01

    Classics is in the news--or on the screen: "Gladiator" a few years ago, "Troy" very recently, "Alexander" as I write. How significant is this current Hollywood fascination with the ancient Greeks and Romans? Or should we take far more seriously the decline of the teaching of the Classical languages in schools, a…

  7. Velopharyngeal Port Status during Classical Singing

    ERIC Educational Resources Information Center

    Tanner, Kristine; Roy, Nelson; Merrill, Ray M.; Power, David

    2005-01-01

    Purpose: This investigation was undertaken to examine the status of the velopharyngeal (VP) port during classical singing. Method: Using aeromechanical instrumentation, nasal airflow (mL/s), oral pressure (cm H[subscript 2]O), and VP orifice area estimates (cm[squared]) were studied in 10 classically trained sopranos during singing and speaking.…

  8. Rediscovering the Classics: The Project Approach.

    ERIC Educational Resources Information Center

    Townsend, Ruth; Lubell, Marcia

    Focusing on seven classics of literature that are most challenging for teachers and students, but which are also a part of the high school literary canon, this book shares ways to create a learner-centered classroom for the study of literature. For each of the seven classics, the book "walks teachers through" the teaching-learning…

  9. Tarnished Gold: Classical Music in America

    ERIC Educational Resources Information Center

    Asia, Daniel

    2010-01-01

    A few articles have appeared recently regarding the subject of the health of classical music (or more broadly, the fine arts) in America. These include "Classical Music's New Golden Age," by Heather Mac Donald, in the "City Journal" and "The Decline of the Audience," by Terry Teachout, in "Commentary." These articles appeared around the time of…

  10. Linguistic Investigations into Ellipsis in Classical Sanskrit

    NASA Astrophysics Data System (ADS)

    Gillon, Brendan S.

    Ellipsis is a common phenomenon of Classical Sanskrit prose. No inventory of the forms of ellipsis in Classical Sanskrit has been made. This paper presents an inventory, based both on a systematic investigation of one text and on examples based on sundry reading.

  11. Converting Projects from STK Classic to STK

    SciTech Connect

    Foucar, James G.

    2014-08-01

    The version of STK (Sierra ToolKit) that has long been provided with Trilinos is no longer supported by the core develop- ment team. With the introduction of a the new STK library into Trilinos, the old STK has been renamed to stk classic. This document contains a rough guide of how to port a stk classic code to STK.

  12. Classical and Quantum-Mechanical State Reconstruction

    ERIC Educational Resources Information Center

    Khanna, F. C.; Mello, P. A.; Revzen, M.

    2012-01-01

    The aim of this paper is to present the subject of state reconstruction in classical and in quantum physics, a subject that deals with the experimentally acquired information that allows the determination of the physical state of a system. Our first purpose is to explain a method for retrieving a classical state in phase space, similar to that…

  13. Milgram's Obedience Study: A Contentious Classic Reinterpreted

    ERIC Educational Resources Information Center

    Griggs, Richard A.

    2017-01-01

    Given the many older criticisms of Milgram's obedience study and the more damning recent criticisms based on analyses of materials available in the Milgram archives at Yale, this study has become a contentious classic. Yet, current social psychology textbooks present it as an uncontentious classic, with no coverage of the recent criticisms and…

  14. Factors Influencing the Learning of Classical Mechanics.

    ERIC Educational Resources Information Center

    Champagne, Audrey B.; And Others

    1980-01-01

    Describes a study investigating the combined effect of certain variables on student achievement in classical mechanics. The purpose was to (1) describe preinstructional knowledge and skills; (2) correlate these variables with the student's success in learning classical mechanics; and (3) develop hypothesis about relationships between these…

  15. Classic and Romantic in Irish Curriculum Development.

    ERIC Educational Resources Information Center

    McKernan, Jim

    Recent trends in curriculum development in Irish post-primary schools are traced according to two models: the classic-centrist and the romantic-decentralist. The classic model, initiated by agencies external to the school, views curriculum development as a science and focuses on accountability and competency-based teaching and testing. The…

  16. The Classical Performing Arts of India.

    ERIC Educational Resources Information Center

    Curtiss, Marie Joy

    A monograph of the numerous activities that have contributed to the current renaissance of India's classical performing arts covers the theoretical aspects, musical instruments, the main schools of classical dance, and drama. Besides the basic research described, the total project produced a set of 300 slides with annotated listing, picturing the…

  17. New Classical and New Keynesian Macroeconomics.

    ERIC Educational Resources Information Center

    Vane, Howard; Snowdon, Brian

    1992-01-01

    Summarizes underlying tenets and policy implications of new classical and new Keynesian macroeconomics. Compares new approaches with orthodox Keynesian and monetarist schools of thought. Identifies the fundamental difference between new classical and new Keynesian models as the assumption regarding the speed of wage and price adjustment following…

  18. Teaching the Classics in High School.

    ERIC Educational Resources Information Center

    Shelley, Anne Crout

    1998-01-01

    Discusses why the classics can be difficult to teach in high schools. Offers suggestions for making difficult literature more approachable for high school students by scaffolding students' engagement with classic texts; building background knowledge; developing vocabulary; facilitating the reading of the text; and through enrichment an extension.…

  19. A Classical Rhetoric for "Powerful" Argumentation.

    ERIC Educational Resources Information Center

    Wiethoff, William E.

    1980-01-01

    Analyzes a 1976 House of Representatives' debate in light of classical writings on the problem of defining and using "power" for rhetorical ends. Outlines the classical solution of powerful diction, brevity, and figures of speech for intensifying the impact of already compelling argument and applies these to the contemporary analysis.…

  20. Quantum phase uncertainties in the classical limit

    NASA Technical Reports Server (NTRS)

    Franson, James D.

    1994-01-01

    Several sources of phase noise, including spontaneous emission noise and the loss of coherence due to which-path information, are examined in the classical limit of high field intensities. Although the origin of these effects may appear to be quantum-mechanical in nature, it is found that classical analogies for these effects exist in the form of chaos.

  1. Classical transport in disordered systems

    NASA Astrophysics Data System (ADS)

    Papaioannou, Antonios

    This thesis reports on the manifestation of structural disorder on molecular transport and it consists of two parts. Part I discusses the relations between classical transport and the underlying structural complexity of the system. Both types of molecular diffusion, namely Gaussian and non- Gaussian are presented and the relevant time regimes are discussed. In addition the concept of structural universality is introduced and connected with the diffusion metrics. One of the most robust techniques for measuring molecular mean square displacements is magnetic resonance. This method requires encoding and subsequently reading out after an experimentally controlled time, a phase φ to the spins using magnetic field gradients. The main limitation for probing short diffusion lengths L(t) ˜ 1micro m with magnetic resonance is the requirement to encode and decode the phase φ in very short time intervals. Therefore, to probe such displacements a special probe was developed equipped with a gradient coil capable of delivering magnetic field gradients of approximately 90 G/cmA . The design of the probe is reported. Part I also includes a discussion of experiments of transport in two qualitatively different disordered phantoms and reports on a direct observation of universality in one-dimension. The results reveal the universal power law scaling of the diffusion coefficient at the long-time regime and illustrate the essence of structural universality by experimentally determining the structure correlation function of the phantoms. In addition, the scaling of the diffusive permeability of the phantoms with respect to the pore size is investigated. Additional work presented includes a detailed study of adsorption of methane gas in Vycor disordered glass. The techniques described in Part I of this thesis are widely used for measuring structural parameters of porous media, such as the surface-to-volume ratio or diffusive permeability. Part II of this thesis discusses the

  2. NUCLEAR THERMOMETERS FOR CLASSICAL NOVAE

    SciTech Connect

    Downen, Lori N.; Iliadis, Christian; Jose, Jordi; Starrfield, Sumner

    2013-01-10

    Classical novae are stellar explosions occurring in binary systems, consisting of a white dwarf and a main-sequence companion. Thermonuclear runaways on the surface of massive white dwarfs, consisting of oxygen and neon, are believed to reach peak temperatures of several hundred million kelvin. These temperatures are strongly correlated with the underlying white dwarf mass. The observational counterparts of such models are likely associated with outbursts that show strong spectral lines of neon in their shells (neon novae). The goals of this work are to investigate how useful elemental abundances are for constraining the peak temperatures achieved during these outbursts and determine how robust 'nova thermometers' are with respect to uncertain nuclear physics input. We present updated observed abundances in neon novae and perform a series of hydrodynamic simulations for several white dwarf masses. We find that the most useful thermometers, N/O, N/Al, O/S, S/Al, O/Na, Na/Al, O/P, and P/Al, are those with the steepest monotonic dependence on peak temperature. The sensitivity of these thermometers to thermonuclear reaction rate variations is explored using post-processing nucleosynthesis simulations. The ratios N/O, N/Al, O/Na, and Na/Al are robust, meaning they are minimally affected by uncertain rates. However, their dependence on peak temperature is relatively weak. The ratios O/S, S/Al, O/P, and P/Al reveal strong dependences on temperature and the poorly known {sup 30}P(p, {gamma}){sup 31}S rate. We compare our model predictions to neon nova observations and obtain the following estimates for the underlying white dwarf masses: 1.34-1.35 M {sub Sun} (V838 Her), 1.18-1.21 M {sub Sun} (V382 Vel), {<=}1.3 M {sub Sun} (V693 CrA), {<=}1.2 M {sub Sun} (LMC 1990 no. 1), and {<=}1.2 M {sub Sun} (QU Vul).

  3. Quantum simulation of classical thermal states.

    PubMed

    Dür, W; Van den Nest, M

    2011-10-21

    We establish a connection between ground states of local quantum Hamiltonians and thermal states of classical spin systems. For any discrete classical statistical mechanical model in any spatial dimension, we find an associated quantum state such that the reduced density operator behaves as the thermal state of the classical system. We show that all these quantum states are unique ground states of a universal 5-body local quantum Hamiltonian acting on a (polynomially enlarged) qubit system on a 2D lattice. The only free parameters of the quantum Hamiltonian are coupling strengths of two-body interactions, which allow one to choose the type and dimension of the classical model as well as the interaction strength and temperature. This opens the possibility to study and simulate classical spin models in arbitrary dimension using a 2D quantum system.

  4. Classical field approach to quantum weak measurements.

    PubMed

    Dressel, Justin; Bliokh, Konstantin Y; Nori, Franco

    2014-03-21

    By generalizing the quantum weak measurement protocol to the case of quantum fields, we show that weak measurements probe an effective classical background field that describes the average field configuration in the spacetime region between pre- and postselection boundary conditions. The classical field is itself a weak value of the corresponding quantum field operator and satisfies equations of motion that extremize an effective action. Weak measurements perturb this effective action, producing measurable changes to the classical field dynamics. As such, weakly measured effects always correspond to an effective classical field. This general result explains why these effects appear to be robust for pre- and postselected ensembles, and why they can also be measured using classical field techniques that are not weak for individual excitations of the field.

  5. Driven topological systems in the classical limit

    NASA Astrophysics Data System (ADS)

    Duncan, Callum W.; Öhberg, Patrik; Valiente, Manuel

    2017-03-01

    Periodically driven quantum systems can exhibit topologically nontrivial behavior, even when their quasienergy bands have zero Chern numbers. Much work has been conducted on noninteracting quantum-mechanical models where this kind of behavior is present. However, the inclusion of interactions in out-of-equilibrium quantum systems can prove to be quite challenging. On the other hand, the classical counterpart of hard-core interactions can be simulated efficiently via constrained random walks. The noninteracting model, proposed by Rudner et al. [Phys. Rev. X 3, 031005 (2013), 10.1103/PhysRevX.3.031005], has a special point for which the system is equivalent to a classical random walk. We consider the classical counterpart of this model, which is exact at a special point even when hard-core interactions are present, and show how these quantitatively affect the edge currents in a strip geometry. We find that the interacting classical system is well described by a mean-field theory. Using this we simulate the dynamics of the classical system, which show that the interactions play the role of Markovian, or time-dependent disorder. By comparing the evolution of classical and quantum edge currents in small lattices, we find regimes where the classical limit considered gives good insight into the quantum problem.

  6. Survival of classic cholera in Bangladesh.

    PubMed

    Siddique, A K; Baqui, A H; Eusof, A; Haider, K; Hossain, M A; Bashir, I; Zaman, K

    1991-05-11

    During the present cholera pandemic the El Tor biotype of Vibrio cholerae has completely displaced the classic biotype, except in Bangladesh. We studied the distribution of these two biotypes in twenty-four rural districts during epidemics in 1988-89; there was clustering of the classic biotype in the southern region and of the El Tor biotype in all other regions. These findings suggest that the southern coastal region is now (and may always have been) the habitat of classic cholera. The selective distribution of V cholerae O1 biotypes in Bangladesh may have been affected by ecological changes occurring in the country.

  7. Failure of classical elasticity in auxetic foams

    NASA Astrophysics Data System (ADS)

    Roh, J. H.; Giller, C. B.; Mott, P. H.; Roland, C. M.

    2013-04-01

    Poisson's ratio, ν, was measured for four materials, a rubbery polymer, a conventional soft foam, and two auxetic foams. We find that for the first two materials, having ν ≥ 0.2, the experimental determinations of Poisson's ratio are in good agreement with values calculated from the shear and tensile moduli using the equations of classical elasticity. However, for the two auxetic materials (ν < 0), the equations of classical elasticity give values significantly different from the measured ν. We offer an interpretation of these results based on a recently published analysis of the bounds on Poisson's ratio for classical elasticity to be applicable.

  8. Coherent quantum states from classical oscillator amplitudes

    NASA Astrophysics Data System (ADS)

    Briggs, John S.; Eisfeld, Alexander

    2012-05-01

    In the first days of quantum mechanics Dirac pointed out an analogy between the time-dependent coefficients of an expansion of the Schrödinger equation and the classical position and momentum variables solving Hamilton's equations. Here it is shown that the analogy can be made an equivalence in that, in principle, systems of classical oscillators can be constructed whose position and momenta variables form time-dependent amplitudes which are identical to the complex quantum amplitudes of the coupled wave function of an N-level quantum system with real coupling matrix elements. Hence classical motion can reproduce quantum coherence.

  9. A classical case of the Gasul phenomenon.

    PubMed

    Sabnis, Girish R; Phadke, Milind S; Kerkar, Prafulla G

    2016-02-01

    This case demonstrates the development of secondary infundibular stenosis in a 10-year-old male child with documented large non-restrictive perimembranous ventricular septal defect in infancy - the classical Gasul phenomenon.

  10. Classic Phenylketonuria: Diagnosis Through Heterozygote Detection

    ERIC Educational Resources Information Center

    Griffin, Robert F.; Elsas, Louis J.

    1975-01-01

    In an attempt to improve the identification of the asymptomatic carrier of classic phenylketonuria (PKU) 59 male and female normal control Ss were differentiated from 18 males and females heterozgous for PKU. (DB)

  11. Secure quantum communication using classical correlated channel

    NASA Astrophysics Data System (ADS)

    Costa, D.; de Almeida, N. G.; Villas-Boas, C. J.

    2016-10-01

    We propose a secure protocol to send quantum information from one part to another without a quantum channel. In our protocol, which resembles quantum teleportation, a sender (Alice) and a receiver (Bob) share classical correlated states instead of EPR ones, with Alice performing measurements in two different bases and then communicating her results to Bob through a classical channel. Our secure quantum communication protocol requires the same amount of classical bits as the standard quantum teleportation protocol. In our scheme, as in the usual quantum teleportation protocol, once the classical channel is established in a secure way, a spy (Eve) will never be able to recover the information of the unknown quantum state, even if she is aware of Alice's measurement results. Security, advantages, and limitations of our protocol are discussed and compared with the standard quantum teleportation protocol.

  12. Three Neglected Advances in Classical Genetics.

    ERIC Educational Resources Information Center

    Miller, Wilmer J.; Hollander, Willard F.

    1995-01-01

    This article describes three advances in classical genetics: improved pedigree charting, use of a standard of reference, and calculation of probabilities in complex assortment. Provides support for the importance of teaching these methods in addition to new techniques. (LZ)

  13. Classical decoherence in a nanomechanical resonator

    NASA Astrophysics Data System (ADS)

    Maillet, Olivier; Fefferman, Andrew; Gazizulin, Rasul; Godfrin, Henri; Bourgeois, Olivier; Collin, Eddy; ULT Grenoble Team

    Decoherence can be viewed either in its quantum picture, where it stands for the loss of phase coherence of a superposition state, or as its classical equivalent, where the phase of an oscillating signal is smeared due to frequency fluctuations. Little is known about quantum coherence of mechanical systems, as opposed to electromagnetic degrees of freedom. Indeed the bridge between quantum and classical physics is under intense investigation, using in particular classical nanomechanical analogues of quantum phenomena. Here we report on a model experiment in which the coherence of a high quality silicon-nitride mechanical resonator is defined in the classical picture. Its intrinsic properties are characterized over an unprecedentedly large dynamic range. By engineering frequency fluctuations, we can create artificial pure dephasing and study its effects on the dynamics of the system. Finally, we develop the methods to characterize pure dephasing that can be applied to a wide range of mechanical devices.

  14. Classical and Quantum Spreading of Position Probability

    ERIC Educational Resources Information Center

    Farina, J. E. G.

    1977-01-01

    Demonstrates that the standard deviation of the position probability of a particle moving freely in one dimension is a function of the standard deviation of its velocity distribution and time in classical or quantum mechanics. (SL)

  15. Classics in the Classroom: Great Expectations Fulfilled.

    ERIC Educational Resources Information Center

    Pearl, Shela

    1986-01-01

    Describes how an English teacher in a Queens, New York, ghetto school introduced her grade nine students to Charles Dickens's "Great Expectations." Focuses on students' responses, which eventually became enthusiastic, and discusses the use of classics within the curriculum. (KH)

  16. Factorizations of one-dimensional classical systems

    SciTech Connect

    Kuru, Senguel; Negro, Javier

    2008-02-15

    A class of one-dimensional classical systems is characterized from an algebraic point of view. The Hamiltonians of these systems are factorized in terms of two functions that together with the Hamiltonian itself close a Poisson algebra. These two functions lead directly to two time-dependent integrals of motion from which the phase motions are derived algebraically. The systems so obtained constitute the classical analogues of the well known factorizable one-dimensional quantum mechanical systems.

  17. Understanding singularities — Classical and quantum

    NASA Astrophysics Data System (ADS)

    Konkowski, Deborah A.; Helliwell, Thomas M.

    2016-01-01

    The definitions of classical and quantum singularities are reviewed. Examples are given of both as well as their utility in general relativity. In particular, the classical and quantum singularity structure of certain interesting conformally static spherically symmetric spacetimes modeling scalar field collapse are reviewed. The spacetimes include the Roberts spacetime, the Husain-Martinez-Nuñez spacetime and the Fonarev spacetime. The importance of understanding spacetime singularity structure is discussed.

  18. Automatic target recognition via classical detection theory

    NASA Astrophysics Data System (ADS)

    Morgan, Douglas R.

    1995-07-01

    Classical Bayesian detection and decision theory applies to arbitrary problems with underlying probabilistic models. When the models describe uncertainties in target type, pose, geometry, surround, scattering phenomena, sensor behavior, and feature extraction, then classical theory directly yields detailed model-based automatic target recognition (ATR) techniques. This paper reviews options and considerations arising under a general Bayesian framework for model- based ATR, including approaches to the major problems of acquiring probabilistic models and of carrying out the indicated Bayesian computations.

  19. Quantum Simulations of Classical Annealing Processes

    NASA Astrophysics Data System (ADS)

    Somma, R. D.; Boixo, S.; Barnum, H.; Knill, E.

    2008-09-01

    We describe a quantum algorithm that solves combinatorial optimization problems by quantum simulation of a classical simulated annealing process. Our algorithm exploits quantum walks and the quantum Zeno effect induced by evolution randomization. It requires order 1/δ steps to find an optimal solution with bounded error probability, where δ is the minimum spectral gap of the stochastic matrices used in the classical annealing process. This is a quadratic improvement over the order 1/δ steps required by the latter.

  20. Quantum and Classical Electrostatics Among Atoms

    NASA Astrophysics Data System (ADS)

    Doerr, T. P.; Obolensky, O. I.; Ogurtsov, A. Y.; Yu, Yi-Kuo

    Quantum theory has been unquestionably successful at describing physics at the atomic scale. However, it becomes more difficult to apply as the system size grows. On the other hand, classical physics breaks down at sufficiently short length scales but is clearly correct at larger distances. The purpose of methods such as QM/MM is to gain the advantages of both quantum and classical regimes: quantum theory should provide accuracy at the shortest scales, and classical theory, with its somewhat more tractable computational demands, allows results to be computed for systems that would be inaccessible with a purely quantum approach. This strategy will be most effective when one knows with good accuracy the length scale at which quantum calculations are no longer necessary and classical calculations are sufficient. To this end, we have performed both classical and quantum calculations for systems comprising a small number of atoms for which experimental data is also available. The classical calculations are fully exact; the quantum calculations are at the MP4(SDTQ)/aug-cc-pV5Z and CCSD(T)/aug-cc-pV5Z levels. The precision of both sets of calculations along with the existence of experimental results allows us to draw conclusions about the range of utility of the respective calculations. This research was supported by the Intramural Research Program of the NIH, NLM and utilized the computational resources of the NIH HPC Biowulf cluster.

  1. Nonlinear atom interferometer surpasses classical precision limit.

    PubMed

    Gross, C; Zibold, T; Nicklas, E; Estève, J; Oberthaler, M K

    2010-04-22

    Interference is fundamental to wave dynamics and quantum mechanics. The quantum wave properties of particles are exploited in metrology using atom interferometers, allowing for high-precision inertia measurements. Furthermore, the state-of-the-art time standard is based on an interferometric technique known as Ramsey spectroscopy. However, the precision of an interferometer is limited by classical statistics owing to the finite number of atoms used to deduce the quantity of interest. Here we show experimentally that the classical precision limit can be surpassed using nonlinear atom interferometry with a Bose-Einstein condensate. Controlled interactions between the atoms lead to non-classical entangled states within the interferometer; this represents an alternative approach to the use of non-classical input states. Extending quantum interferometry to the regime of large atom number, we find that phase sensitivity is enhanced by 15 per cent relative to that in an ideal classical measurement. Our nonlinear atomic beam splitter follows the 'one-axis-twisting' scheme and implements interaction control using a narrow Feshbach resonance. We perform noise tomography of the quantum state within the interferometer and detect coherent spin squeezing with a squeezing factor of -8.2 dB (refs 11-15). The results provide information on the many-particle quantum state, and imply the entanglement of 170 atoms.

  2. Unraveling Quantum Annealers using Classical Hardness.

    PubMed

    Martin-Mayor, Victor; Hen, Itay

    2015-10-20

    Recent advances in quantum technology have led to the development and manufacturing of experimental programmable quantum annealing optimizers that contain hundreds of quantum bits. These optimizers, commonly referred to as 'D-Wave' chips, promise to solve practical optimization problems potentially faster than conventional 'classical' computers. Attempts to quantify the quantum nature of these chips have been met with both excitement and skepticism but have also brought up numerous fundamental questions pertaining to the distinguishability of experimental quantum annealers from their classical thermal counterparts. Inspired by recent results in spin-glass theory that recognize 'temperature chaos' as the underlying mechanism responsible for the computational intractability of hard optimization problems, we devise a general method to quantify the performance of quantum annealers on optimization problems suffering from varying degrees of temperature chaos: A superior performance of quantum annealers over classical algorithms on these may allude to the role that quantum effects play in providing speedup. We utilize our method to experimentally study the D-Wave Two chip on different temperature-chaotic problems and find, surprisingly, that its performance scales unfavorably as compared to several analogous classical algorithms. We detect, quantify and discuss several purely classical effects that possibly mask the quantum behavior of the chip.

  3. The classical model for moment tensors

    NASA Astrophysics Data System (ADS)

    Tape, W.; Tape, C.

    2013-12-01

    A seismic moment tensor is a description of an earthquake source, but the description is indirect. The moment tensor describes seismic radiation rather than the actual physical process that initiates the radiation. A moment tensor 'model' then ties the physical process to the moment tensor. The model is not unique, and the physical process is therefore not unique. In the classical moment tensor model (Aki and Richards, 1980), an earthquake arises from slip along a planar fault, but with the slip not necessarily in the plane of the fault. The model specifies the resulting moment tensor in terms of the slip vector, the fault normal vector, and the Lame elastic parameters, assuming isotropy. We review the classical model in the context of the fundamental lune. The lune is closely related to the space of moment tensors, and it provides a setting that is conceptually natural as well as pictorial. In addition to the classical model, we consider a crack plus double couple model (CDC model) in which a moment tensor is regarded as the sum of a crack tensor and a double couple. A compilation of full moment tensors from the literature reveals large deviations in Poisson's ratio as implied by the classical model. Either the classical model is inadequate or the published full moment tensors have very large uncertainties. We question the common interpretation of the isotropic component as a volume change in the source region.

  4. Effective dynamics of a classical point charge

    SciTech Connect

    Polonyi, Janos

    2014-03-15

    The effective Lagrangian of a point charge is derived by eliminating the electromagnetic field within the framework of the classical closed time path formalism. The short distance singularity of the electromagnetic field is regulated by an UV cutoff. The Abraham–Lorentz force is recovered and its similarity to quantum anomalies is underlined. The full cutoff-dependent linearized equation of motion is obtained, no runaway trajectories are found but the effective dynamics shows acausality if the cutoff is beyond the classical charge radius. The strength of the radiation reaction force displays a pole in its cutoff-dependence in a manner reminiscent of the Landau-pole of perturbative QED. Similarity between the dynamical breakdown of the time reversal invariance and dynamical symmetry breaking is pointed out. -- Highlights: •Extension of the classical action principle for dissipative systems. •New derivation of the Abraham–Lorentz force for a point charge. •Absence of a runaway solution of the Abraham–Lorentz force. •Acausality in classical electrodynamics. •Renormalization of classical electrodynamics of point charges.

  5. Population structure of the Classic period Maya.

    PubMed

    Scherer, Andrew K

    2007-03-01

    This study examines the population structure of Classic period (A.D. 250-900) Maya populations through analysis of odontometric variation of 827 skeletons from 12 archaeological sites in Mexico, Guatemala, Belize, and Honduras. The hypothesis that isolation by distance characterized Classic period Maya population structure is tested using Relethford and Blangero's (Hum Biol 62 (1990) 5-25) approach to R matrix analysis for quantitative traits. These results provide important biological data for understanding ancient Maya population history, particularly the effects of the competing Tikal and Calakmul hegemonies on patterns of lowland Maya site interaction. An overall F(ST) of 0.018 is found for the Maya area, indicating little among-group variation for the Classic Maya sites tested. Principal coordinates plots derived from the R matrix analysis show little regional patterning in the data, though the geographic outliers of Kaminaljuyu and a pooled Pacific Coast sample did not cluster with the lowland Maya sites. Mantel tests comparing the biological distance matrix to a geographic distance matrix found no association between genetic and geographic distance. In the Relethford-Blangero analysis, most sites possess negative or near-zero residuals, indicating minimal extraregional gene flow. The exceptions were Barton Ramie, Kaminaljuyu, and Seibal. A scaled R matrix analysis clarifies that genetic drift is a consideration for understanding Classic Maya population structure. All results indicate that isolation by distance does not describe Classic period Maya population structure.

  6. Quantum-classical crossover in electrodynamics

    SciTech Connect

    Polonyi, Janos

    2006-09-15

    A classical field theory is proposed for the electric current and the electromagnetic field interpolating between microscopic and macroscopic domains. It represents a generalization of the density functional for the dynamics of the current and the electromagnetic field in the quantum side of the crossover and reproduces standard classical electrodynamics on the other side. The effective action derived in the closed time path formalism and the equations of motion follow from the variational principle. The polarization of the Dirac-sea can be taken into account in the quadratic approximation of the action by the introduction of the deplacement field strengths as in conventional classical electrodynamics. Decoherence appears naturally as a simple one-loop effect in this formalism. It is argued that the radiation time arrow is generated from the quantum boundary conditions in time by decoherence at the quantum-classical crossover and the Abraham-Lorentz force arises from the accelerating charge or from other charges in the macroscopic or the microscopic side, respectively. The functional form of the quantum renormalization group, the generalization of the renormalization group method for the density matrix, is proposed to follow the scale dependence through the quantum-classical crossover in a systematical manner.

  7. Exchange potentials for semi-classical electrons.

    PubMed

    Herzfeld, Judith; Ekesan, Solen

    2016-11-09

    Semi-classical electrons offer access to efficient and intuitive simulations of chemical reactions. As for any treatment of fermions, the greatest difficulty is in accounting for anti-symmetry effects. Semi-classical efforts to-date either reference Slater-determinants from ab initio treatments or adopt a heuristic approach inspired by density functional treatments. Here we revisit the problem with a combined approach. We conclude that semi-classical electrons need to reference a non-conventional wave function and find that (1) contrary to earlier suppositions, contributions from the electrostatic terms in the Hamiltonian are of similar magnitude to those from the kinetic terms and (2) the former point to a need to supplement pair potentials with 3-body potentials. The first result explains features of reported heuristic potentials, and the second provides a firm footing for extending the transferability of potentials across a wider range of elements and bonding scenarios.

  8. Non-Classical Inhibition of Carbonic Anhydrase

    PubMed Central

    Lomelino, Carrie L.; Supuran, Claudiu T.; McKenna, Robert

    2016-01-01

    Specific isoforms from the carbonic anhydrase (CA) family of zinc metalloenzymes have been associated with a variety of diseases. Isoform-specific carbonic anhydrase inhibitors (CAIs) are therefore a major focus of attention for specific disease treatments. Classical CAIs, primarily sulfonamide-based compounds and their bioisosteres, are examined as antiglaucoma, antiepileptic, antiobesity, antineuropathic pain and anticancer compounds. However, many sulfonamide compounds inhibit all CA isoforms nonspecifically, diluting drug effectiveness and causing undesired side effects due to off-target inhibition. In addition, a small but significant percentage of the general population cannot be treated with sulfonamide-based compounds due to a sulfa allergy. Therefore, CAIs must be developed that are not only isoform specific, but also non-classical, i.e. not based on sulfonamides, sulfamates, or sulfamides. This review covers the classes of non-classical CAIs and the recent advances in the development of isoform-specific inhibitors based on phenols, polyamines, coumarins and their derivatives. PMID:27438828

  9. Fractionalized Z_{2} Classical Heisenberg Spin Liquids.

    PubMed

    Rehn, J; Sen, Arnab; Moessner, R

    2017-01-27

    Quantum spin systems are by now known to exhibit a large number of different classes of spin liquid phases. By contrast, for classical Heisenberg models, only one kind of fractionalized spin liquid phase, the so-called Coulomb or U(1) spin liquid, has until recently been identified: This exhibits algebraic spin correlations and impurity moments, "orphan spins," whose size is a fraction of that of the underlying microscopic degrees of freedom. Here, we present two Heisenberg models exhibiting fractionalization in combination with exponentially decaying correlations. These can be thought of as a classical continuous spin version of a Z_{2} spin liquid. Our work suggests a systematic search and classification of classical spin liquids as a worthwhile endeavor.

  10. Machian classical and semiclassical emergent time

    NASA Astrophysics Data System (ADS)

    Anderson, Edward

    2014-01-01

    Classical and semiclassical schemes are presented that are timeless at the primary level and recover time from Mach’s ‘time is to be abstracted from change’ principle at the emergent secondary level. The semiclassical scheme is a Machian variant of the semiclassical approach to the problem of time in quantum gravity. The classical scheme is Barbour’s, cast here explicitly as the classical precursor of the semiclassical approach. Thus the two schemes have been married up, as equally-Machian and necessarily distinct, since the latter’s timestandard is abstracted in part from quantum change. I provide perturbative schemes for these in which the timefunction is to be determined rather than assumed. This paper is useful modelling as regards the Halliwell-Hawking arena for the quantum origin of the inhomogeneous cosmological fluctuations.

  11. Quantum approach to classical statistical mechanics.

    PubMed

    Somma, R D; Batista, C D; Ortiz, G

    2007-07-20

    We present a new approach to study the thermodynamic properties of d-dimensional classical systems by reducing the problem to the computation of ground state properties of a d-dimensional quantum model. This classical-to-quantum mapping allows us to extend the scope of standard optimization methods by unifying them under a general framework. The quantum annealing method is naturally extended to simulate classical systems at finite temperatures. We derive the rates to assure convergence to the optimal thermodynamic state using the adiabatic theorem of quantum mechanics. For simulated and quantum annealing, we obtain the asymptotic rates of T(t) approximately (pN)/(k(B)logt) and gamma(t) approximately (Nt)(-c/N), for the temperature and magnetic field, respectively. Other annealing strategies are also discussed.

  12. Classical Ising model test for quantum circuits

    NASA Astrophysics Data System (ADS)

    Geraci, Joseph; Lidar, Daniel A.

    2010-07-01

    We exploit a recently constructed mapping between quantum circuits and graphs in order to prove that circuits corresponding to certain planar graphs can be efficiently simulated classically. The proof uses an expression for the Ising model partition function in terms of quadratically signed weight enumerators (QWGTs), which are polynomials that arise naturally in an expansion of quantum circuits in terms of rotations involving Pauli matrices. We combine this expression with a known efficient classical algorithm for the Ising partition function of any planar graph in the absence of an external magnetic field, and the Robertson-Seymour theorem from graph theory. We give as an example a set of quantum circuits with a small number of non-nearest-neighbor gates which admit an efficient classical simulation.

  13. Quantum and classical optics-emerging links

    NASA Astrophysics Data System (ADS)

    Eberly, J. H.; Qian, Xiao-Feng; Qasimi, Asma Al; Ali, Hazrat; Alonso, M. A.; Gutiérrez-Cuevas, R.; Little, Bethany J.; Howell, John C.; Malhotra, Tanya; Vamivakas, A. N.

    2016-06-01

    Quantum optics and classical optics are linked in ways that are becoming apparent as a result of numerous recent detailed examinations of the relationships that elementary notions of optics have with each other. These elementary notions include interference, polarization, coherence, complementarity and entanglement. All of them are present in both quantum and classical optics. They have historic origins, and at least partly for this reason not all of them have quantitative definitions that are universally accepted. This makes further investigation into their engagement in optics very desirable. We pay particular attention to effects that arise from the mere co-existence of separately identifiable and readily available vector spaces. Exploitation of these vector-space relationships are shown to have unfamiliar theoretical implications and new options for observation. It is our goal to bring emerging quantum-classical links into wider view and to indicate directions in which forthcoming and future work will promote discussion and lead to unified understanding.

  14. Voice disorders in children with classic galactosemia.

    PubMed

    Potter, Nancy L

    2011-04-01

    Children with classic galactosemia are at risk for motor speech disorders resulting from disruptions in motor planning and programming (childhood apraxia of speech or CAS) or motor execution (dysarthria). In the present study of 33 children with classic galactosemia, 21% were diagnosed with CAS, 3% with ataxic dysarthria, and 3% with mixed CAS-dysarthria. Voice disorders due to laryngeal insufficiency were common in children with dysarthria and co-occurred with CAS. Most (58%) of the children with classic galactosemia had decreased respiratory-phonatory support for speech, and 33% had disturbed vocal quality that was indicative of cerebellar dysfunction. Three children, two diagnosed with CAS and one not diagnosed with a motor speech disorder, had vocal tremors. Treatment of voice dysfunction in neurogenic speech disorders is discussed.

  15. Modeling Classical Heat Conduction in FLAG

    SciTech Connect

    Ramsey, Scott D.; Hendon, Raymond Cori

    2015-01-12

    The Los Alamos National Laboratory FLAG code contains both electron and ion heat conduction modules; these have been constructed to be directly relevant to user application problems. However, formal code verification of these modules requires quantitative comparison to exact solutions of the underlying mathematical models. A wide variety of exact solutions to the classical heat conduction equation are available for this purpose. This report summarizes efforts involving the representation of the classical heat conduction equation as following from the large electron-ion coupling limit of the electron and ion 3T temperature equations, subject to electron and ion conduction processes. In FLAG, this limiting behavior is quantitatively verified using a simple exact solution of the classical heat conduction equation. For this test problem, both heat conduction modules produce nearly identical spatial electron and ion temperature profiles that converge at slightly less than 2nd order to the corresponding exact solution.

  16. Observable signatures of a classical transition

    SciTech Connect

    Johnson, Matthew C.; Lin, Wei E-mail: lewisweilin@gmail.com

    2016-03-01

    Eternal inflation arising from a potential landscape predicts that our universe is one realization of many possible cosmological histories. One way to access different cosmological histories is via the nucleation of bubble universes from a metastable false vacuum. Another way to sample different cosmological histories is via classical transitions, the creation of pocket universes through the collision between bubbles. Using relativistic numerical simulations, we examine the possibility of observationally determining if our observable universe resulted from a classical transition. We find that classical transitions produce spatially infinite, approximately open Friedman-Robertson-Walker universes. The leading set of observables in the aftermath of a classical transition are negative spatial curvature and a contribution to the Cosmic Microwave Background temperature quadrupole. The level of curvature and magnitude of the quadrupole are dependent on the position of the observer, and we determine the possible range of observables for two classes of single-scalar field models. For the first class, where the inflationary phase has a lower energy than the vacuum preceding the classical transition, the magnitude of the observed quadrupole generally falls to zero with distance from the collision while the spatial curvature grows to a constant. For the second class, where the inflationary phase has a higher energy than the vacuum preceding the classical transition, the magnitude of the observed quadrupole generically falls to zero with distance from the collision while the spatial curvature grows without bound. We find that the magnitude of the quadrupole and curvature grow with increasing centre of mass energy of the collision, and explore variations of the parameters in the scalar field lagrangian.

  17. Decoherence, chaos, the quantum and the classical

    SciTech Connect

    Zurek, W.H.; Paz, J.P.

    1994-04-01

    The key ideas of the environment-induced decoherence approach are reviewed. Application of decoherence to the transition from quantum to classical in open quantum systems with chaotic classical analogs is described. The arrow of time is, in this context, a result of the information loss to the correlations with the environment. The asymptotic rate of entropy production (which is reached quickly, on the dynamical timescale) is independent of the details of the coupling of the quantum system to the environment, and is set by the Lyapunov exponents. We also briefly outline the existential interpretation of quantum mechanics, justifying the slogan ``No information without representation.``

  18. Classical ultra-relativistic scattering in ADD

    NASA Astrophysics Data System (ADS)

    Gal'tsov, Dmitry V.; Kofinas, Georgios; Spirin, Pavel; Tomaras, Theodore N.

    2009-05-01

    The classical differential cross-section is calculated for high-energy small-angle gravitational scattering in the factorizable model with toroidal extra dimensions. The three main features of the classical computation are: (a) It involves summation over the infinite Kaluza-Klein towers but, contrary to the Born amplitude, it is finite with no need of an ultraviolet cutoff. (b) It is shown to correspond to the non-perturbative saddle-point approximation of the eikonal amplitude, obtained by the summation of an infinite number of ladder graphs of the quantum theory. (c) In the absence of extra dimensions it reproduces all previously known results.

  19. Communication: quantum dynamics in classical spin baths.

    PubMed

    Sergi, Alessandro

    2013-07-21

    A formalism for studying the dynamics of quantum systems embedded in classical spin baths is introduced. The theory is based on generalized antisymmetric brackets and predicts the presence of open-path off-diagonal geometric phases in the evolution of the density matrix. The weak coupling limit of the equation can be integrated by standard algorithms and provides a non-Markovian approach to the computer simulation of quantum systems in classical spin environments. It is expected that the theory and numerical schemes presented here have a wide applicability.

  20. Classical noise, quantum noise and secure communication

    NASA Astrophysics Data System (ADS)

    Tannous, C.; Langlois, J.

    2016-01-01

    Secure communication based on message encryption might be performed by combining the message with controlled noise (called pseudo-noise) as performed in spread-spectrum communication used presently in Wi-Fi and smartphone telecommunication systems. Quantum communication based on entanglement is another route for securing communications as demonstrated by several important experiments described in this work. The central role played by the photon in unifying the description of classical and quantum noise as major ingredients of secure communication systems is highlighted and described on the basis of the classical and quantum fluctuation dissipation theorems.

  1. Classical swine fever in China: a minireview.

    PubMed

    Luo, Yuzi; Li, Su; Sun, Yuan; Qiu, Hua-Ji

    2014-08-06

    Classical swine fever (CSF), caused by Classical swine fever virus (CSFV), is an OIE-listed, highly contagious, often fatal disease of swine worldwide. Currently, the disease is controlled by prophylactic vaccination in China and many other countries using the modified live vaccines derived from C-strain, which was developed in China in the mid-1950s. This minireview summarizes the epidemiology, diagnostic assays, control and challenges of CSF in China. Though CSF is essentially under control, complete eradication of CSF in China remains a challenging task and needs long-term, joint efforts of stakeholders.

  2. Quantization of soluble classical constrained systems

    SciTech Connect

    Belhadi, Z.; Menas, F.; Bérard, A.; Mohrbach, H.

    2014-12-15

    The derivation of the brackets among coordinates and momenta for classical constrained systems is a necessary step toward their quantization. Here we present a new approach for the determination of the classical brackets which does neither require Dirac’s formalism nor the symplectic method of Faddeev and Jackiw. This approach is based on the computation of the brackets between the constants of integration of the exact solutions of the equations of motion. From them all brackets of the dynamical variables of the system can be deduced in a straightforward way.

  3. The classic. Review article: Traffic accidents. 1966.

    PubMed

    Tscherne, H

    2013-09-01

    This Classic Article is a translation of the original work by Prof. Harald Tscherne, Der Straßenunfall [Traffic Accidents]. An accompanying biographical sketch of Prof. Tscherne is available at DOI 10.1007/s11999-013-3011-x . An online version of the original German article is available as supplemental material. The Classic Article is reproduced with permission from Brüder Hollinek & Co. GesmbH, Purkersdorf, Austria. The original article was published in Wien Med Wochenschr. 1966;116:105-108. (Translated by Dr. Roman Pfeifer.).

  4. Are Volume Plasmons Excitable by Classical Light?

    NASA Astrophysics Data System (ADS)

    Höflich, Katja; Gösele, Ulrich; Christiansen, Silke

    2009-08-01

    Volume plasmons are collective eigenmodes of the free-electron gas inside a metal. Because of their longitudinal character and the transversal nature of light, the photoexcitation of volume plasmons is forbidden in classical electrodynamics. Nevertheless, we show their existence for metallic nanoshells using analytical solutions of the classical scattering problem. Solely for the case of a vanishing real part of the shell permittivity, a local maximum at the natural plasma frequency appears in the extinction spectra. For explaining our observations, we suggest a simple physical picture which is supported by examples on silver and gold shells.

  5. Thermodynamic integration from classical to quantum mechanics.

    PubMed

    Habershon, Scott; Manolopoulos, David E

    2011-12-14

    We present a new method for calculating quantum mechanical corrections to classical free energies, based on thermodynamic integration from classical to quantum mechanics. In contrast to previous methods, our method is numerically stable even in the presence of strong quantum delocalization. We first illustrate the method and its relationship to a well-established method with an analysis of a one-dimensional harmonic oscillator. We then show that our method can be used to calculate the quantum mechanical contributions to the free energies of ice and water for a flexible water model, a problem for which the established method is unstable.

  6. Force fields for classical molecular dynamics.

    PubMed

    Monticelli, Luca; Tieleman, D Peter

    2013-01-01

    In this chapter we review the basic features and the principles underlying molecular mechanics force fields commonly used in molecular modeling of biological macromolecules. We start by summarizing the historical background and then describe classical pairwise additive potential energy functions. We introduce the problem of the calculation of nonbonded interactions, of particular importance for charged macromolecules. Different parameterization philosophies are then presented, followed by a section on force field validation. We conclude with a brief overview on future perspectives for the development of classical force fields.

  7. Simulation of Pake doublet with classical spins and correspondence between the quantum and classical approaches

    NASA Astrophysics Data System (ADS)

    Henner, Victor K.; Klots, Andrey; Belozerova, Tatyana

    2016-12-01

    Problems of interacting quantum magnetic moments become exponentially complex with increasing number of particles. As a result, classical equations are often used to model spin systems. In this paper we show that a classical spins based approach can be used to describe the phenomena essentially quantum in nature such as of the Pake doublet.

  8. Comparisons of classical chemical dynamics simulations of the unimolecular decomposition of classical and quantum microcanonical ensembles.

    PubMed

    Manikandan, Paranjothy; Hase, William L

    2012-05-14

    Previous studies have shown that classical trajectory simulations often give accurate results for short-time intramolecular and unimolecular dynamics, particularly for initial non-random energy distributions. To obtain such agreement between experiment and simulation, the appropriate distributions must be sampled to choose initial coordinates and momenta for the ensemble of trajectories. If a molecule's classical phase space is sampled randomly, its initial decomposition will give the classical anharmonic microcanonical (RRKM) unimolecular rate constant for its decomposition. For the work presented here, classical trajectory simulations of the unimolecular decomposition of quantum and classical microcanonical ensembles, at the same fixed total energy, are compared. In contrast to the classical microcanonical ensemble, the quantum microcanonical ensemble does not sample the phase space randomly. The simulations were performed for CH(4), C(2)H(5), and Cl(-)---CH(3)Br using both analytic potential energy surfaces and direct dynamics methods. Previous studies identified intrinsic RRKM dynamics for CH(4) and C(2)H(5), but intrinsic non-RRKM dynamics for Cl(-)---CH(3)Br. Rate constants calculated from trajectories obtained by the time propagation of the classical and quantum microcanonical ensembles are compared with the corresponding harmonic RRKM estimates to obtain anharmonic corrections to the RRKM rate constants. The relevance and accuracy of the classical trajectory simulation of the quantum microcanonical ensemble, for obtaining the quantum anharmonic RRKM rate constant, is discussed.

  9. Unraveling Quantum Annealers using Classical Hardness

    NASA Astrophysics Data System (ADS)

    Martin-Mayor, Victor; Hen, Itay

    2015-10-01

    Recent advances in quantum technology have led to the development and manufacturing of experimental programmable quantum annealing optimizers that contain hundreds of quantum bits. These optimizers, commonly referred to as ‘D-Wave’ chips, promise to solve practical optimization problems potentially faster than conventional ‘classical’ computers. Attempts to quantify the quantum nature of these chips have been met with both excitement and skepticism but have also brought up numerous fundamental questions pertaining to the distinguishability of experimental quantum annealers from their classical thermal counterparts. Inspired by recent results in spin-glass theory that recognize ‘temperature chaos’ as the underlying mechanism responsible for the computational intractability of hard optimization problems, we devise a general method to quantify the performance of quantum annealers on optimization problems suffering from varying degrees of temperature chaos: A superior performance of quantum annealers over classical algorithms on these may allude to the role that quantum effects play in providing speedup. We utilize our method to experimentally study the D-Wave Two chip on different temperature-chaotic problems and find, surprisingly, that its performance scales unfavorably as compared to several analogous classical algorithms. We detect, quantify and discuss several purely classical effects that possibly mask the quantum behavior of the chip.

  10. Can Communicative Principles Enhance Classical Language Acquisition?

    ERIC Educational Resources Information Center

    Overland, Paul; Fields, Lee; Noonan, Jennifer

    2011-01-01

    Is it feasible for nonfluent instructors to teach Biblical Hebrew by communicative principles? If it is feasible, will communicative instruction enhance postsecondary learning of a classical language? To begin answering these questions, two consultants representing second language acquisition (SLA) and technology-assisted language learning led 8…

  11. Using CAS to Solve Classical Mathematics Problems

    ERIC Educational Resources Information Center

    Burke, Maurice J.; Burroughs, Elizabeth A.

    2009-01-01

    Historically, calculus has displaced many algebraic methods for solving classical problems. This article illustrates an algebraic method for finding the zeros of polynomial functions that is closely related to Newton's method (devised in 1669, published in 1711), which is encountered in calculus. By exploring this problem, precalculus students…

  12. Comparison of Classical and Quantum Mechanical Uncertainties.

    ERIC Educational Resources Information Center

    Peslak, John, Jr.

    1979-01-01

    Comparisons are made for the particle-in-a-box, the harmonic oscillator, and the one-electron atom. A classical uncertainty principle is derived and compared with its quantum-mechanical counterpart. The results are discussed in terms of the statistical interpretation of the uncertainty principle. (Author/BB)

  13. Entanglement in Quantum-Classical Hybrid

    NASA Technical Reports Server (NTRS)

    Zak, Michail

    2011-01-01

    It is noted that the phenomenon of entanglement is not a prerogative of quantum systems, but also occurs in other, non-classical systems such as quantum-classical hybrids, and covers the concept of entanglement as a special type of global constraint imposed upon a broad class of dynamical systems. Application of hybrid systems for physics of life, as well as for quantum-inspired computing, has been outlined. In representing the Schroedinger equation in the Madelung form, there is feedback from the Liouville equation to the Hamilton-Jacobi equation in the form of the quantum potential. Preserving the same topology, the innovators replaced the quantum potential with other types of feedback, and investigated the property of these hybrid systems. A function of probability density has been introduced. Non-locality associated with a global geometrical constraint that leads to an entanglement effect was demonstrated. Despite such a quantum like characteristic, the hybrid can be of classical scale and all the measurements can be performed classically. This new emergence of entanglement sheds light on the concept of non-locality in physics.

  14. Selected topics from classical bacterial genetics.

    PubMed

    Raleigh, Elisabeth A; Elbing, Karen; Brent, Roger

    2002-08-01

    Current cloning technology exploits many facts learned from classical bacterial genetics. This unit covers those that are critical to understanding the techniques described in this book. Topics include antibiotics, the LAC operon, the F factor, nonsense suppressors, genetic markers, genotype and phenotype, DNA restriction, modification and methylation and recombination.

  15. Unraveling a classical mechanics brain twister

    NASA Astrophysics Data System (ADS)

    Paris, Norman; Broide, Michael L.

    2011-12-01

    We present a comprehensive analysis of an intriguing classical mechanics problem involving the coupled motion of two blocks. The problem illustrates fundamental physics concepts and theoretical techniques. We solve the equations of motion numerically and gain insight into common misconceptions about this system. The problem provides rich opportunities for student investigations using analytical and numerical methods.

  16. The classical pion field in a nucleus

    NASA Astrophysics Data System (ADS)

    Ripka, Georges

    2008-12-01

    A self-consistent symmetry arises when the nucleon angular momentum j and the isospin t are coupled to a grand spin G. Closed G shells become sources of a classical pion field with a hedgehog shape. Although the amplitude of the pion field, as measured by the chiral angle, is small, it is found to perturb significantly the energies of the nucleon orbits.

  17. Concerning gauge field fluctuations around classical configurations

    SciTech Connect

    Dietrich, Dennis D.

    2009-05-15

    We treat the fluctuations of non-Abelian gauge fields around a classical configuration by means of a transformation from the Yang-Mills gauge field to a homogeneously transforming field variable. We use the formalism to compute the effective action induced by these fluctuations in a static background without Wu-Yang ambiguity.

  18. Essays on Classical Rhetoric and Modern Discourse.

    ERIC Educational Resources Information Center

    Connors, Robert J., Ed.; And Others

    Noting the rediscovery by composition scholars of the tradition of classical rhetoric, this collection of essays explores the resurgence in the teaching of written discourse in college English departments. The 18 articles and their authors are as follows: (1) "The Revival of Rhetoric in America," by Robert Connors, Lisa Ede, and Andrea…

  19. Medical and rehabilitation issues in classical ballet.

    PubMed

    Stretanski, Michael F; Weber, G J

    2002-05-01

    Classical ballet is a demanding professional occupation, with participants who are often underserved in terms of accurate diagnosis and appropriate comprehensive medical care. The view that follows is designed to be as global and insightful as published to date. Specific rehabilitation considerations, dance mechanics, idiosyncratic differential diagnosis, and personality and equipment issues are discussed, and a rational view of dogma is presented.

  20. The Oxford Treasury of Classic Poems.

    ERIC Educational Resources Information Center

    Harrison, Michael, Ed.; Stuart-Clark, Christopher, Ed.

    This book contains over 90 classic poems for children. The collection of poems includes nonsense verse by Lear and Carroll, story poems by Tennyson and Keats, and humorous poems by Belloc and Betjeman. The collection also includes poems by modern poets, such as Charles Causley, Ted Hughes, John Agard, Roger McGough, and Stevie Smith. The…

  1. Foreign Language, the Classics, and College Admissions.

    ERIC Educational Resources Information Center

    LaFleur, Richard A.

    1993-01-01

    This article reports the results of a survey, funded by the American Classical League (ACL) and conducted during 1990-91, that assessed attitudes toward high school foreign-language study, in particular the study of Latin and Greek, in the college admissions process. (21 references) (VWL)

  2. Gender and the Classics Curriculum: A Survey

    ERIC Educational Resources Information Center

    Blundell, Sue

    2009-01-01

    A survey was carried out in 2006 of all the UK universities where Classics and Ancient History degrees are taught at undergraduate level. The results reveal that nearly half of these courses include at least one dedicated gender module, and that the great majority also have gender embedded in the content of modules dealing with other topics.…

  3. Classical Pragmatism on Mind and Rationality

    ERIC Educational Resources Information Center

    Maattanen, Pentti

    2005-01-01

    One of the major changes in twentieth century philosophy was the so-called linguistic turn, in which natural and formal languages became central subjects of study. This meant that theories of meaning became mostly about linguistic meaning, thinking was now analyzed in terms of symbol manipulation, and rules of classical logic formed the nucleus of…

  4. Classic hallucinogens in the treatment of addictions.

    PubMed

    Bogenschutz, Michael P; Johnson, Matthew W

    2016-01-04

    Addictive disorders are very common and have devastating individual and social consequences. Currently available treatment is moderately effective at best. After many years of neglect, there is renewed interest in potential clinical uses for classic hallucinogens in the treatment of addictions and other behavioral health conditions. In this paper we provide a comprehensive review of both historical and recent clinical research on the use of classic hallucinogens in the treatment of addiction, selectively review other relevant research concerning hallucinogens, and suggest directions for future research. Clinical trial data are very limited except for the use of LSD in the treatment of alcoholism, where a meta-analysis of controlled trials has demonstrated a consistent and clinically significant beneficial effect of high-dose LSD. Recent pilot studies of psilocybin-assisted treatment of nicotine and alcohol dependence had strikingly positive outcomes, but controlled trials will be necessary to evaluate the efficacy of these treatments. Although plausible biological mechanisms have been proposed, currently the strongest evidence is for the role of mystical or other meaningful experiences as mediators of therapeutic effects. Classic hallucinogens have an excellent record of safety in the context of clinical research. Given our limited understanding of the clinically relevant effects of classic hallucinogens, there is a wealth of opportunities for research that could contribute important new knowledge and potentially lead to valuable new treatments for addiction.

  5. Metal Ion Modeling Using Classical Mechanics.

    PubMed

    Li, Pengfei; Merz, Kenneth M

    2017-02-08

    Metal ions play significant roles in numerous fields including chemistry, geochemistry, biochemistry, and materials science. With computational tools increasingly becoming important in chemical research, methods have emerged to effectively face the challenge of modeling metal ions in the gas, aqueous, and solid phases. Herein, we review both quantum and classical modeling strategies for metal ion-containing systems that have been developed over the past few decades. This Review focuses on classical metal ion modeling based on unpolarized models (including the nonbonded, bonded, cationic dummy atom, and combined models), polarizable models (e.g., the fluctuating charge, Drude oscillator, and the induced dipole models), the angular overlap model, and valence bond-based models. Quantum mechanical studies of metal ion-containing systems at the semiempirical, ab initio, and density functional levels of theory are reviewed as well with a particular focus on how these methods inform classical modeling efforts. Finally, conclusions and future prospects and directions are offered that will further enhance the classical modeling of metal ion-containing systems.

  6. The Strange World of Classical Physics

    ERIC Educational Resources Information Center

    Green, David

    2010-01-01

    We have heard many times that the commonsense world of classical physics was shattered by Einstein's revelation of the laws of relativity. This is certainly true; the shift from our everyday notions of time and space to those revealed by relativity is one of the greatest stretches the mind can make. What is seldom appreciated is that the laws of…

  7. Metal Ion Modeling Using Classical Mechanics

    PubMed Central

    2017-01-01

    Metal ions play significant roles in numerous fields including chemistry, geochemistry, biochemistry, and materials science. With computational tools increasingly becoming important in chemical research, methods have emerged to effectively face the challenge of modeling metal ions in the gas, aqueous, and solid phases. Herein, we review both quantum and classical modeling strategies for metal ion-containing systems that have been developed over the past few decades. This Review focuses on classical metal ion modeling based on unpolarized models (including the nonbonded, bonded, cationic dummy atom, and combined models), polarizable models (e.g., the fluctuating charge, Drude oscillator, and the induced dipole models), the angular overlap model, and valence bond-based models. Quantum mechanical studies of metal ion-containing systems at the semiempirical, ab initio, and density functional levels of theory are reviewed as well with a particular focus on how these methods inform classical modeling efforts. Finally, conclusions and future prospects and directions are offered that will further enhance the classical modeling of metal ion-containing systems. PMID:28045509

  8. On the emergence of classical gravity

    NASA Astrophysics Data System (ADS)

    Larjo, Klaus

    In this thesis I will discuss how certain black holes arise as an effective, thermodynamical description from non-singular microstates in string theory. This provides a possible solution to the information paradox, and strengthens the case for treating black holes as thermodynamical objects. I will characterize the data defining a microstate of a black hole in several settings, and demonstrate that most of the data is unmeasurable for a classical observer. I will further show that the data that is measurable is universal for nearly all microstates, making it impossible for a classical observer to distinguish between microstates, thus giving rise to an effective statistical description for the black hole. In the first half of the thesis I will work with two specific systems: the half-BPS sector of [Special characters omitted.] = 4 super Yang-Mills the and the conformal field theory corresponding to the D1/D5 system; in both cases the high degree of symmetry present provides great control over potentially intractable computations. For these systems, I will further specify the conditions a quantum mechanical microstate must satisfy in order to have a classical description in terms of a unique metric, and define a 'metric operator' whose eigenstates correspond to classical geometries. In the second half of the thesis I will consider a much broader setting, general [Special characters omitted.] = I superconformal quiver gauge the= ories and their dual gravity theories, and demonstrate that a similar effective description arises also in this setting.

  9. Maxwell and the classical wave particle dualism.

    PubMed

    Mendonça, J T

    2008-05-28

    Maxwell's equations are one of the greatest theoretical achievements in physics of all times. They have survived three successive theoretical revolutions, associated with the advent of relativity, quantum mechanics and modern quantum field theory. In particular, they provide the theoretical framework for the understanding of the classical wave particle dualism.

  10. Louis Guttman's Contributions to Classical Test Theory

    ERIC Educational Resources Information Center

    Zimmerman, Donald W.; Williams, Richard H.; Zumbo, Bruno D.; Ross, Donald

    2005-01-01

    This article focuses on Louis Guttman's contributions to the classical theory of educational and psychological tests, one of the lesser known of his many contributions to quantitative methods in the social sciences. Guttman's work in this field provided a rigorous mathematical basis for ideas that, for many decades after Spearman's initial work,…

  11. Classic Readers Theatre for Young Adults.

    ERIC Educational Resources Information Center

    Barchers, Suzanne I.; Kroll, Jennifer L.

    This book presents 16 original scripts that have been adapted from classic works of literature for use for readers theatre with young adults and ESL (English as a Second Language) students. Adaptations of the following works are included: "Little Women" (Louisa May Alcott); episodes from "Don Quixote" (Miguel de Cervantes; "The Necklace" (Guy de…

  12. Unified classical path theories of pressure broadening.

    NASA Technical Reports Server (NTRS)

    Bottcher, C.

    1971-01-01

    Derivation of a unified classical path theory of pressure broadening, using only elementary concepts. It is shown that the theory of Smith, Cooper and Vidal (1969) is only correct at all frequencies to first order in the number density of perturbers.

  13. An Approach to Teaching Classical Chinese Poetry.

    ERIC Educational Resources Information Center

    Hung, Ming-shui

    1980-01-01

    English translations can be used to teach classical Chinese poetry to students above the intermediate level who have a limited vocabulary. To overcome this deficiency, and to bridge the gap between vernacular and literary Chinese, several texts are suggested. Examples are given to show the benefit of English translations. (PJM)

  14. Unraveling Quantum Annealers using Classical Hardness

    PubMed Central

    Martin-Mayor, Victor; Hen, Itay

    2015-01-01

    Recent advances in quantum technology have led to the development and manufacturing of experimental programmable quantum annealing optimizers that contain hundreds of quantum bits. These optimizers, commonly referred to as ‘D-Wave’ chips, promise to solve practical optimization problems potentially faster than conventional ‘classical’ computers. Attempts to quantify the quantum nature of these chips have been met with both excitement and skepticism but have also brought up numerous fundamental questions pertaining to the distinguishability of experimental quantum annealers from their classical thermal counterparts. Inspired by recent results in spin-glass theory that recognize ‘temperature chaos’ as the underlying mechanism responsible for the computational intractability of hard optimization problems, we devise a general method to quantify the performance of quantum annealers on optimization problems suffering from varying degrees of temperature chaos: A superior performance of quantum annealers over classical algorithms on these may allude to the role that quantum effects play in providing speedup. We utilize our method to experimentally study the D-Wave Two chip on different temperature-chaotic problems and find, surprisingly, that its performance scales unfavorably as compared to several analogous classical algorithms. We detect, quantify and discuss several purely classical effects that possibly mask the quantum behavior of the chip. PMID:26483257

  15. The Classical Version of Stokes' Theorem Revisited

    ERIC Educational Resources Information Center

    Markvorsen, Steen

    2008-01-01

    Using only fairly simple and elementary considerations--essentially from first year undergraduate mathematics--we show how the classical Stokes' theorem for any given surface and vector field in R[superscript 3] follows from an application of Gauss' divergence theorem to a suitable modification of the vector field in a tubular shell around the…

  16. Fertility preservation in female classic galactosemia patients.

    PubMed

    van Erven, Britt; Gubbels, Cynthia S; van Golde, Ron J; Dunselman, Gerard A; Derhaag, Josien G; de Wert, Guido; Geraedts, Joep P; Bosch, Annet M; Treacy, Eileen P; Welt, Corrine K; Berry, Gerard T; Rubio-Gozalbo, M Estela

    2013-07-16

    Almost every female classic galactosemia patient develops primary ovarian insufficiency (POI) as a diet-independent complication of the disease. This is a major concern for patients and their parents, and physicians are often asked about possible options to preserve fertility. Unfortunately, there are no recommendations on fertility preservation in this group. The unique pathophysiology of classic galactosemia with a severely reduced follicle pool at an early age requires an adjusted approach. In this article recommendations for physicians based on current knowledge concerning galactosemia and fertility preservation are made. Fertility preservation is only likely to be successful in very young prepubertal patients. In this group, cryopreservation of ovarian tissue is currently the only available technique. However, this technique is not ready for clinical application, it is considered experimental and reduces the ovarian reserve. Fertility preservation at an early age also raises ethical questions that should be taken into account. In addition, spontaneous conception despite POI is well described in classic galactosemia. The uncertainty surrounding fertility preservation and the significant chance of spontaneous pregnancy warrant counseling towards conservative application of these techniques. We propose that fertility preservation should only be offered with appropriate institutional research ethics approval to classic galactosemia girls at a young prepubertal age.

  17. Studying the Leaders of Classical Antiquity.

    ERIC Educational Resources Information Center

    Moritz, Helen E.

    This paper describes a graduate seminar for educational administrators, using works of ancient Greek and Roman literature as bases for the consideration of organization and leadership problems identified in theoretical literature. The seminar was team taught by professors from the Departments of Educational Administration and Classics at the…

  18. Classical enhancement of quantum vacuum fluctuations

    NASA Astrophysics Data System (ADS)

    De Lorenci, V. A.; Ford, L. H.

    2017-01-01

    We propose a mechanism for the enhancement of vacuum fluctuations by means of a classical field. The basic idea is that if an observable quantity depends quadratically upon a quantum field, such as the electric field, then the application of a classical field produces a cross term between the classical and quantum fields. This cross term may be significantly larger than the purely quantum part, but also undergoes fluctuations driven by the quantum field. We illustrate this effect in a model for light-cone fluctuations involving pulses in a nonlinear dielectric. Vacuum electric field fluctuations produce fluctuations in the speed of a probe pulse, and form an analog model for quantum gravity effects. If the material has a nonzero third-order susceptibility, then the fractional light speed fluctuations are proportional to the square of the fluctuating electric field. Hence the application of a classical electric field can enhance the speed fluctuations. We give an example where this enhancement can be an increase of 1 order of magnitude, increasing the possibility of observing the effect.

  19. Report of the Colloquium on the Classics in Education, 1965.

    ERIC Educational Resources Information Center

    Else, Gerald F., Ed.

    This is the report of an international meeting on the Classics, conducted August 1965 in London, England. Resolutions adopted by the Colloquium, minutes of group sessions, papers, and national reports on the state of classical education are presented. Group sessions discuss the teaching of classical languages, classical literatures, and ancient…

  20. Cholera outbreaks in the classical biotype era.

    PubMed

    Siddique, A K; Cash, Richard

    2014-01-01

    In the Indian subcontinent description of a disease resembling cholera has been mentioned in Sushruta Samita, estimated to have been written between ~400 and 500 BC. It is however not clear whether the disease known today as cholera caused by Vibrio cholerae Vibrio cholerae O1 is the evolutionary progression of the ancient disease. The modern history of cholera began in 1817 when an explosive epidemic broke out in the Ganges River Delta region of Bengal. This was the first of the seven recorded cholera pandemics cholera pandemics that affected nearly the entire world and caused hundreds of thousands of deaths. The bacterium responsible for this human disease was first recognised during the fifth pandemic and was named V. cholerae which was grouped as O1, and was further differentiated into Classical and El Tor biotypes. It is now known that the fifth and the sixth pandemics were caused by the V. cholerae O1 of the Classical biotype Classical biotype and the seventh by the El Tor biotype El Tor biotype . The El Tor biotype of V. cholerae, which originated in Indonesia Indonesia and shortly thereafter began to spread in the early 1960s. Within the span of 50 years the El Tor biotype had invaded nearly the entire world, completely displacing the Classical biotype from all the countries except Bangladesh. What prompted the earlier pandemics to begin is not clearly understood, nor do we know how and why they ended. The success of the seventh pandemic clone over the pre-existing sixth pandemic strain remains largely an unsolved mystery. Why classical biotype eventually disappeared from the world remains to be explained. For nearly three decades (1963-1991) during the Seventh cholera pandemic seventh pandemic, cholera in Bangladesh has recorded a unique history of co-existence of Classical and El Tor biotypes of V. cholerae O1 as epidemic and endemic strain. This long co-existence has provided us with great opportunity to improve our understanding of the disease itself

  1. Classical Photogrammetry and Uav - Selected Ascpects

    NASA Astrophysics Data System (ADS)

    Mikrut, S.

    2016-06-01

    The UAV technology seems to be highly future-oriented due to its low costs as compared to traditional aerial images taken from classical photogrammetry aircrafts. The AGH University of Science and Technology in Cracow - Department of Geoinformation, Photogrammetry and Environmental Remote Sensing focuses mainly on geometry and radiometry of recorded images. Various scientific research centres all over the world have been conducting the relevant research for years. The paper presents selected aspects of processing digital images made with the UAV technology. It provides on a practical example a comparison between a digital image taken from an airborne (classical) height, and the one made from an UAV level. In his research the author of the paper is trying to find an answer to the question: to what extent does the UAV technology diverge today from classical photogrammetry, and what are the advantages and disadvantages of both methods? The flight plan was made over the Tokarnia Village Museum (more than 0.5 km2) for two separate flights: the first was made by an UAV - System FT-03A built by FlyTech Solution Ltd. The second was made with the use of a classical photogrammetric Cesna aircraft furnished with an airborne photogrammetric camera (Ultra Cam Eagle). Both sets of photographs were taken with pixel size of about 3 cm, in order to have reliable data allowing for both systems to be compared. The project has made aerotriangulation independently for the two flights. The DTM was generated automatically, and the last step was the generation of an orthophoto. The geometry of images was checked under the process of aerotriangulation. To compare the accuracy of these two flights, control and check points were used. RMSE were calculated. The radiometry was checked by a visual method and using the author's own algorithm for feature extraction (to define edges with subpixel accuracy). After initial pre-processing of data, the images were put together, and shown side by side

  2. Phase difference enhancement with classical intensity interferometry

    NASA Astrophysics Data System (ADS)

    Shirai, Tomohiro

    2016-12-01

    It is demonstrated theoretically and experimentally that, as a novel function of classical intensity interferometry, a phase difference distribution recorded in the form of an interferogram can be enhanced by a factor of 2 on the basis of the classical intensity correlation. Such phase difference enhancement which is also referred to as phase difference amplification is, in general, known to be practically important since it increases sensitivity and accuracy in interferometric measurements. The method proposed in this study prevails over the existing methods in the sense that it can be readily implemented without difficulty in comparison with all other methods so far proposed, although the phase difference enhancement is limited to a factor of 2 in our method and thus so is the improvement of sensitivity and accuracy.

  3. Fast forward to the classical adiabatic invariant

    NASA Astrophysics Data System (ADS)

    Jarzynski, Christopher; Deffner, Sebastian; Patra, Ayoti; Subaşı, Yiǧit

    2017-03-01

    We show how the classical action, an adiabatic invariant, can be preserved under nonadiabatic conditions. Specifically, for a time-dependent Hamiltonian H =p2/2 m +U (q ,t ) in one degree of freedom, and for an arbitrary choice of action I0, we construct a so-called fast-forward potential energy function VFF(q ,t ) that, when added to H , guides all trajectories with initial action I0 to end with the same value of action. We use this result to construct a local dynamical invariant J (q ,p ,t ) whose value remains constant along these trajectories. We illustrate our results with numerical simulations. Finally, we sketch how our classical results may be used to design approximate quantum shortcuts to adiabaticity.

  4. Macroscopic quantum mechanics in a classical spacetime.

    PubMed

    Yang, Huan; Miao, Haixing; Lee, Da-Shin; Helou, Bassam; Chen, Yanbei

    2013-04-26

    We apply the many-particle Schrödinger-Newton equation, which describes the coevolution of a many-particle quantum wave function and a classical space-time geometry, to macroscopic mechanical objects. By averaging over motions of the objects' internal degrees of freedom, we obtain an effective Schrödinger-Newton equation for their centers of mass, which can be monitored and manipulated at quantum levels by state-of-the-art optomechanics experiments. For a single macroscopic object moving quantum mechanically within a harmonic potential well, its quantum uncertainty is found to evolve at a frequency different from its classical eigenfrequency-with a difference that depends on the internal structure of the object-and can be observable using current technology. For several objects, the Schrödinger-Newton equation predicts semiclassical motions just like Newtonian physics, yet quantum uncertainty cannot be transferred from one object to another.

  5. Isoperiodic classical systems and their quantum counterparts

    NASA Astrophysics Data System (ADS)

    Asorey, M.; Cariñena, J. F.; Marmo, G.; Perelomov, A.

    2007-06-01

    One-dimensional isoperiodic classical systems have been first analyzed by Abel. Abel's characterization can be extended for singular potentials and potentials which are not defined on the whole real line. The standard shear equivalence of isoperiodic potentials can also be extended by using reflection and inversion transformations. We provide a full characterization of isoperiodic rational potentials showing that they are connected by translations, reflections or Joukowski transformations. Upon quantization many of these isoperiodic systems fail to exhibit identical quantum energy spectra. This anomaly occurs at order O( ℏ2) because semiclassical corrections of energy levels of order O( ℏ) are identical for all isoperiodic systems. We analyze families of systems where this quantum anomaly occurs and some special systems where the spectral identity is preserved by quantization. Conversely, we point out the existence of isospectral quantum systems which do not correspond to isoperiodic classical systems.

  6. Classical simulation of quantum fields I

    NASA Astrophysics Data System (ADS)

    Hirayama, T.; Holdom, B.

    2006-10-01

    We study classical field theories in a background field configuration where all modes of the theory are excited, matching the zero-point energy spectrum of quantum field theory. Our construction involves elements of a theory of classical electrodynamics by Wheeler-Feynman and the theory of stochastic electrodynamics of Boyer. The nonperturbative effects of interactions in these theories can be very efficiently studied on the lattice. In lambda phi(4) theory in 1 + 1 dimensions, we find results, in particular, for mass renormalization and the critical coupling for symmetry breaking that are in agreement with their quantum counterparts. We then study the perturbative expansion of the n-point Green's functions and find a loop expansion very similar to that of quantum field theory. When compared to the usual Feynman rules, we find some differences associated with particular combinations of internal lines going on-shell simultaneously.

  7. Coherently enhanced measurements in classical mechanics

    NASA Astrophysics Data System (ADS)

    Braun, Daniel; Popescu, Sandu

    2014-08-01

    In all quantitative sciences, it is common practice to increase the signal-to-noise ratio of noisy measurements by measuring identically prepared systems N times and averaging the measurement results. This leads to a scaling of the sensitivity as 1/√N, known in quantum measurement theory as the "standard quantum limit" (SQL). It is known that if one puts the N systems into an entangled state, a scaling as 1/N can be achieved, the socalled "Heisenberg limit" (HL), but decoherence problems have so far prevented implementation of such protocols for large N. Here we show that a method of coherent averaging inspired by a recent entanglement-free quantum enhanced measurement protocol is capable of achieving a sensitivity that scales as 1/N in a purely classical setup. This may substantially improve the measurement of very weak interactions in the classical realm, and, in particular, open a novel route to measuring the gravitational constant with enhanced precision.

  8. Hidden invariance of the free classical particle

    SciTech Connect

    Garcia, S. )

    1994-06-01

    A formalism describing the dynamics of classical and quantum systems from a group theoretical point of view is presented. We apply it to the simple example of the classical free particle. The Galileo group [ital G] is the symmetry group of the free equations of motion. Consideration of the free particle Lagrangian semi-invariance under [ital G] leads to a larger symmetry group, which is a central extension of the Galileo group by the real numbers. We study the dynamics associated with this group, and characterize quantities like Noether invariants and evolution equations in terms of group geometric objects. An extension of the Galileo group by [ital U](1) leads to quantum mechanics.

  9. Quantum and classical phases in optomechanics

    NASA Astrophysics Data System (ADS)

    Armata, Federico; Latmiral, Ludovico; Pikovski, Igor; Vanner, Michael R.; Brukner, Časlav; Kim, M. S.

    2016-06-01

    The control of quantum systems requires the ability to change and read-out the phase of a system. The noncommutativity of canonical conjugate operators can induce phases on quantum systems, which can be employed for implementing phase gates and for precision measurements. Here we study the phase acquired by a radiation field after its radiation pressure interaction with a mechanical oscillator, and compare the classical and quantum contributions. The classical description can reproduce the nonlinearity induced by the mechanical oscillator and the loss of correlations between mechanics and optical field at certain interaction times. Such features alone are therefore insufficient for probing the quantum nature of the interaction. Our results thus isolate genuine quantum contributions of the optomechanical interaction that could be probed in current experiments.

  10. Classical sequential growth dynamics for causal sets

    NASA Astrophysics Data System (ADS)

    Rideout, D. P.; Sorkin, R. D.

    2000-01-01

    Starting from certain causality conditions and a discrete form of general covariance, we derive a very general family of classically stochastic, sequential growth dynamics for causal sets. The resulting theories provide a relatively accessible ``halfway house'' to full quantum gravity that possibly contains the latter's classical limit (general relativity). Because they can be expressed in terms of state models for an assembly of Ising spins residing on the relations of the causal set, these theories also illustrate how nongravitational matter can arise dynamically from the causal set without having to be built in at the fundamental level. Additionally, our results bring into focus some interpretive issues of importance for a causal set dynamics and for quantum gravity more generally.

  11. Quantum-classical path integral. I. Classical memory and weak quantum nonlocality.

    PubMed

    Lambert, Roberto; Makri, Nancy

    2012-12-14

    We consider rigorous path integral descriptions of the dynamics of a quantum system coupled to a polyatomic environment, assuming that the latter is well approximated by classical trajectories. Earlier work has derived semiclassical or purely classical expressions for the influence functional from the environment, which should be sufficiently accurate for many situations, but the evaluation of quantum-(semi)classical path integral (QCPI) expressions has not been practical for large-scale simulation because the interaction with the environment introduces couplings nonlocal in time. In this work, we analyze the nature of the effects on a system from its environment in light of the observation [N. Makri, J. Chem. Phys. 109, 2994 (1998)] that true nonlocality in the path integral is a strictly quantum mechanical phenomenon. If the environment is classical, the path integral becomes local and can be evaluated in a stepwise fashion along classical trajectories of the free solvent. This simple "classical path" limit of QCPI captures fully the decoherence of the system via a classical mechanism. Small corrections to the classical path QCPI approximation may be obtained via an inexpensive random hop QCPI model, which accounts for some "back reaction" effects. Exploiting the finite length of nonlocality, we argue that further inclusion of quantum decoherence is possible via an iterative evaluation of the path integral. Finally, we show that the sum of the quantum amplitude factors with respect to the system paths leads to a smooth integrand as a function of trajectory initial conditions, allowing the use of Monte Carlo methods for the multidimensional phase space integral.

  12. New variables for classical and quantum gravity

    NASA Technical Reports Server (NTRS)

    Ashtekar, Abhay

    1986-01-01

    A Hamiltonian formulation of general relativity based on certain spinorial variables is introduced. These variables simplify the constraints of general relativity considerably and enable one to imbed the constraint surface in the phase space of Einstein's theory into that of Yang-Mills theory. The imbedding suggests new ways of attacking a number of problems in both classical and quantum gravity. Some illustrative applications are discussed.

  13. Wei-Norman equations for classical groups

    NASA Astrophysics Data System (ADS)

    Charzyński, Szymon; Kuś, Marek

    2015-08-01

    We show that the nonlinear autonomous Wei-Norman equations, expressing the solution of a linear system of non-autonomous equations on a Lie algebra, can be reduced to the hierarchy of matrix Riccati equations in the case of all classical simple Lie algebras. The result generalizes our previous one concerning the complex Lie algebra of the special linear group. We show that it cannot be extended to all simple Lie algebras, in particular to the exceptional G2 algebra.

  14. Maxwellian distribution in non-classical regime

    NASA Astrophysics Data System (ADS)

    Mohazzabi, Pirooz; L. Helvey, Shannon; McCumber, Jeremy

    2002-12-01

    A molecular dynamics investigation shows that the assumption of molecular chaos remains valid in the non-classical regime. Consequently, the velocity distribution function of an extremely dense system of spinless particles relaxes into Maxwellian, even in the presence of arbitrary interactions between the particles of the system. Systems with densities exceeding 30 times solid densities are investigated using a soft Lennard-Jones interparticle potential energy function.

  15. INCLINATION MIXING IN THE CLASSICAL KUIPER BELT

    SciTech Connect

    Volk, Kathryn; Malhotra, Renu

    2011-07-20

    We investigate the long-term evolution of the inclinations of the known classical and resonant Kuiper Belt objects (KBOs). This is partially motivated by the observed bimodal inclination distribution and by the putative physical differences between the low- and high-inclination populations. We find that some classical KBOs undergo large changes in inclination over gigayear timescales, which means that a current member of the low-inclination population may have been in the high-inclination population in the past, and vice versa. The dynamical mechanisms responsible for the time variability of inclinations are predominantly distant encounters with Neptune and chaotic diffusion near the boundaries of mean motion resonances. We reassess the correlations between inclination and physical properties including inclination time variability. We find that the size-inclination and color-inclination correlations are less statistically significant than previously reported (mostly due to the increased size of the data set since previous works with some contribution from inclination variability). The time variability of inclinations does not change the previous finding that binary classical KBOs have lower inclinations than non-binary objects. Our study of resonant objects in the classical Kuiper Belt region includes objects in the 3:2, 7:4, 2:1, and eight higher-order mean motion resonances. We find that these objects (some of which were previously classified as non-resonant) undergo larger changes in inclination compared to the non-resonant population, indicating that their current inclinations are not generally representative of their original inclinations. They are also less stable on gigayear timescales.

  16. Semi-classical methods in nuclear physics

    NASA Astrophysics Data System (ADS)

    Brink, David M.

    These lecture notes present an introduction to some semi-classical techniques which have applications in nuclear physics. Topics discussed include the WKB method, approaches based on the Feynman path integral, the Gutzwiller trace formula for level density fluctuations and the Thomas-Fermi approximation and the Vlasov equation for many-body problems. There are applications to heavy ion fusion reactions, bremsstrahlung emission in alpha decay and nuclear response functions.

  17. Classical Analogs of a Diatomic Chain

    SciTech Connect

    Gutierrez, L.; Diaz-de-Anda, A.; Mendez-Sanchez, R. A.; Morales, A.; Flores, J.; Monsivais, G.

    2010-12-21

    Using one dimensional rods with different configurations classical analogs of quantum mechanical systems frequently used in solid state physics can be obtained. Among this analogs we have recently discussed locally periodic rods which lead to band spectra; the effect of a topological defect, and the Wannier Stark ladders. In this paper, we present an elastic analog of the diatomic chain and show how the acoustical and optical bands emerge, as well of the nature of the wave amplitudes.

  18. Large numbers hypothesis. I - Classical formalism

    NASA Technical Reports Server (NTRS)

    Adams, P. J.

    1982-01-01

    A self-consistent formulation of physics at the classical level embodying Dirac's large numbers hypothesis (LNH) is developed based on units covariance. A scalar 'field' phi(x) is introduced and some fundamental results are derived from the resultant equations. Some unusual properties of phi are noted such as the fact that phi cannot be the correspondence limit of a normal quantum scalar field.

  19. Electromagnetically induced classical and quantum Lau effect

    NASA Astrophysics Data System (ADS)

    Qiu, Tianhui; Yang, Guojian; Xiong, Jun; Xu, Deqin

    2016-07-01

    We present two schemes of Lau effect for an object, an electromagnetically induced grating generated based on the electromagnetically induced effect. The Lau interference pattern is detected either directly in the way of the traditional Lau effect measurement with a classical thermal light being the imaging light, or indirectly and nonlocally in the way of two-photon coincidence measurement with a pair of entangled photons being the imaging light.

  20. Uniform Additivity in Classical and Quantum Information

    NASA Astrophysics Data System (ADS)

    Cross, Andrew; Li, Ke; Smith, Graeme

    2017-01-01

    Information theory quantifies the optimal rates of resource interconversions, usually in terms of entropies. However, nonadditivity often makes evaluating entropic formulas intractable. In a few auspicious cases, additivity allows a full characterization of optimal rates. We study uniform additivity of formulas, which is easily evaluated and captures all known additive quantum formulas. Our complete characterization of uniform additivity exposes an intriguing new additive quantity and identifies a remarkable coincidence—the classical and quantum uniformly additive functions with one auxiliary variable are identical.

  1. Time in classical and in quantum mechanics

    NASA Astrophysics Data System (ADS)

    Elçi, A.

    2010-07-01

    This paper presents an analysis of the time concept in classical mechanics from the perspective of the invariants of a motion. The analysis shows that there is a conceptual gap concerning time in the Dirac-Heisenberg-von Neumann formalism and that Bohr's complementarity principle does not fill the gap. In the Dirac-Heisenberg-von Neumann formalism, a particle's properties are represented by Heisenberg matrices. This axiom is the source of the time problem in quantum mechanics.

  2. Lie algebras of classical and stochastic electrodynamics

    NASA Astrophysics Data System (ADS)

    Neto, J. J. Soares; Vianna, J. D. M.

    1994-03-01

    The Lie algebras associated with infinitesimal symmetry transformations of third-order differential equations of interest to classical electrodynamics and stochastic electrodynamics have been obtained. The structure constants for a general case are presented and the Lie algebra for each particular application is easily achieved. By the method used here it is not necessary to know the explicit expressions of the infinitesimal generators in order to determine the structure constants of the Lie algebra.

  3. On Logical Error Underlying Classical Mechanics

    NASA Astrophysics Data System (ADS)

    Kalanov, Temur Z.

    2012-03-01

    The logical analysis of the general accepted description of mechanical motion of material point M in classical mechanics is proposed. The key idea of the analysis is as follows. Let point M be moved in the positive direction of the axis O 1ptx. Motion is characterized by a change of coordinate x,( t ) -- continuous function of time t(because motion is a change in general). If δ,->;0;δ,;=;0, then δ,;->;0δ,;=;0, i.e., according to practice and formal logic, value of coordinate does not change and, hence, motion does not exist. But, contrary to practice and formal logic, differential calculus and classical mechanics contain the assertion that velocity δ,;->;0;δ,δ,;exists without motion. Then velocity δ,;->;0;δ,δ,;is not real (i.e. not physical) quantity, but fictitious quantity. Therefore, use of non-physical (unreal) quantity (i.e. the first and second derivatives of function) in classical mechanics is a logic error.

  4. The classical model for moment tensors

    NASA Astrophysics Data System (ADS)

    Tape, Walter; Tape, Carl

    2013-12-01

    A seismic moment tensor is a description of an earthquake source, but the description is indirect. The moment tensor describes seismic radiation rather than the actual physical process that initiates the radiation. A moment tensor `model' then ties the physical process to the moment tensor. The model is not unique, and the physical process is therefore not unique. In the classical moment tensor model, an earthquake arises from slip along a planar fault, but with the slip not necessarily in the plane of the fault. The model specifies the resulting moment tensor in terms of the slip vector, the fault normal vector and the Lamé elastic parameters, assuming isotropy. We review the classical model in the context of the fundamental lune. The lune is closely related to the space of moment tensors, and it provides a setting that is conceptually natural as well as pictorial. In addition to the classical model, we consider a crack plus double-couple model (CDC model) in which a moment tensor is regarded as the sum of a crack tensor and a double couple.

  5. Classical Hamiltonian structures in wave packet dynamics

    NASA Astrophysics Data System (ADS)

    Gray, Stephen K.; Verosky, John M.

    1994-04-01

    The general, N state matrix representation of the time-dependent Schrödinger equation is equivalent to an N degree of freedom classical Hamiltonian system. We describe how classical mechanical methods and ideas can be applied towards understanding and modeling exact quantum dynamics. Two applications are presented. First, we illustrate how qualitative insights may be gained by treating the two state problem with a time-dependent coupling. In the case of periodic coupling, Poincaré surfaces of section are used to view the quantum dynamics, and features such as the Floquet modes take on interesting interpretations. The second application illustrates computational implications by showing how Liouville's theorem, or more generally the symplectic nature of classical Hamiltonian dynamics, provides a new perspective for carrying out numerical wave packet propagation. We show how certain simple and explicit symplectic integrators can be used to numerically propagate wave packets. The approach is illustrated with an application to the problem of a diatomic molecule interacting with a laser, although it and related approaches may be useful for describing a variety of problems.

  6. Acoustical study of classical Peking Opera singing.

    PubMed

    Sundberg, Johan; Gu, Lide; Huang, Qiang; Huang, Ping

    2012-03-01

    Acoustic characteristics of classical opera singing differ considerably between the Western and the Chinese cultures. Singers in the classical Peking opera tradition specialize on one out of a limited number of standard roles. Audio and electroglottograph signals were recorded for four performers of the Old Man role and three performers of the Colorful Face role. Recordings were made of the singers' speech and when they sang recitatives and songs from their roles. Sound pressure level, fundamental frequency, and spectrum characteristics were analyzed. Histograms showing the distribution of fundamental frequency showed marked peaks for the songs, suggesting a scale tone structure. Some of the intervals between these peaks were similar to those used in Western music. Vibrato rate was about 3.5Hz, that is, considerably slower than in Western classical singing. Spectra of vibrato-free tones contained unbroken series of harmonic partials sometimes reaching up to 17 000Hz. Long-term-average spectrum (LTAS) curves showed no trace of a singer's formant cluster. However, the Colorful Face role singers' LTAS showed a marked peak near 3300Hz, somewhat similar to that found in Western pop music singers. The mean LTAS spectrum slope between 700 and 6000Hz decreased by about 0.2dB/octave per dB of equivalent sound level.

  7. Low Mach Number Simulations of Classical Novae

    NASA Astrophysics Data System (ADS)

    Krueger, Brendan K.; Calder, A. C.; Zingale, M.; Almgren, A. S.; Bell, J. B.; Nonaka, A.

    2012-01-01

    Classical novae are thermonuclear explosions in the accreted layer on the surface of a white dwarf star. The manner in which convective flow interacts with the underlying white dwarf plays a critical role in determining the composition of the accreted layer and the energy release in the outburst. Studies of these complex reactive flows are typically limited by the available computing technology. I am applying a new low Mach number simulation code, MAESTRO, to study classical novae. MAESTRO filters out acoustic waves, allowing much larger time steps without restricting temperature or density perturbations, which in turn enables simulations of much longer time scales. With this unique tool, I have been exploring the development of convection and subsequent mixing in classical novae and their impact on the overall evolution of the outburst. I will present results from multidimensional simulations and quantify the character of the convection and mixing. This work was supported by NASA under grant No. NNX09AD19G and LLNL under contract B59328.

  8. Defining Astrology in Ancient and Classical History

    NASA Astrophysics Data System (ADS)

    Campion, Nicholas

    2015-05-01

    Astrology in the ancient and classical worlds can be partly defined by its role, and partly by the way in which scholars spoke about it. The problem is complicated by the fact that the word is Greek - it has no Babylonian or Egyptian cognates - and even in Greece it was interchangeable with its cousin, 'astronomy'. Yet if we are to understand the role of the sky, stars and planets in culture, debates about the nature of ancient astrology, by both classical and modern scholars, must be taken into account. This talk will consider modern scholars' typologies of ancient astrology, together with ancient debates from Cicero in the 1st century BC, to Plotinus (204/5-270 AD) and Isidore of Seville (c. 560 - 4 April 636). It will consider the implications for our understanding of astronomy's role in culture, and conclude that in the classical period astrology may be best understood through its diversity and allegiance to competing philosophies, and that its functions were therefore similarly varied.

  9. Fundamental frequency from classical molecular dynamics.

    PubMed

    Yamada, Tomonori; Aida, Misako

    2015-02-07

    We give a theoretical validation for calculating fundamental frequencies of a molecule from classical molecular dynamics (MD) when its anharmonicity is small enough to be treated by perturbation theory. We specifically give concrete answers to the following questions: (1) What is the appropriate initial condition of classical MD to calculate the fundamental frequency? (2) From that condition, how accurately can we extract fundamental frequencies of a molecule? (3) What is the benefit of using ab initio MD for frequency calculations? Our analytical approaches to those questions are classical and quantum normal form theories. As numerical examples we perform two types of MD to calculate fundamental frequencies of H2O with MP2/aug-cc-pVTZ: one is based on the quartic force field and the other one is direct ab initio MD, where the potential energies and the gradients are calculated on the fly. From those calculations, we show comparisons of the frequencies from MD with the post vibrational self-consistent field calculations, second- and fourth-order perturbation theories, and experiments. We also apply direct ab initio MD to frequency calculations of C-H vibrational modes of tetracene and naphthalene. We conclude that MD can give the same accuracy in fundamental frequency calculation as second-order perturbation theory but the computational cost is lower for large molecules.

  10. Classical and quantum-mechanical state reconstruction

    NASA Astrophysics Data System (ADS)

    Khanna, F. C.; Mello, P. A.; Revzen, M.

    2012-07-01

    The aim of this paper is to present the subject of state reconstruction in classical and in quantum physics, a subject that deals with the experimentally acquired information that allows the determination of the physical state of a system. Our first purpose is to explain a method for retrieving a classical state in phase space, similar to that used in medical imaging known as computer-aided tomography. It is remarkable that this method can be taken over to quantum mechanics, where it leads to a description of the quantum state in terms of the Wigner function which, although it may take on negative values, plays the role of the probability density in phase space in classical physics. We then present another approach to quantum state reconstruction based on the notion of mutually unbiased bases—a notion of current research interest, for which we give explanatory remarks—and indicate the relation between these two approaches. Since the subject of state reconstruction is rarely considered at the level of textbooks, the presentation in this paper is aimed at graduate-level readers.

  11. Large classical universes emerging from quantum cosmology

    SciTech Connect

    Pinto-Neto, Nelson

    2009-04-15

    It is generally believed that one cannot obtain a large universe from quantum cosmological models without an inflationary phase in the classical expanding era because the typical size of the universe after leaving the quantum regime should be around the Planck length, and the standard decelerated classical expansion after that is not sufficient to enlarge the universe in the time available. For instance, in many quantum minisuperspace bouncing models studied in the literature, solutions where the universe leaves the quantum regime in the expanding phase with appropriate size have negligible probability amplitude with respect to solutions leaving this regime around the Planck length. In this paper, I present a general class of moving Gaussian solutions of the Wheeler-DeWitt equation where the velocity of the wave in minisuperspace along the scale factor axis, which is the new large parameter introduced in order to circumvent the above-mentioned problem, induces a large acceleration around the quantum bounce, forcing the universe to leave the quantum regime sufficiently big to increase afterwards to the present size, without needing any classical inflationary phase in between, and with reasonable relative probability amplitudes with respect to models leaving the quantum regime around the Planck scale. Furthermore, linear perturbations around this background model are free of any trans-Planckian problem.

  12. Quantum vs. classical walks with memory two

    NASA Astrophysics Data System (ADS)

    Dimcovic, Zlatko; Kovchegov, Yevgeniy

    2010-03-01

    Quantum walks is an emerging field in quantum computing. It is expected to become the next most effective tool in speeding up quantum algorithms, possibly achieving the similar gain in speed as was the case with Gibbs sampling in classical computing. There already exist examples of super-exponential speed up using only quantum walks. Markov chains, or random walks on graphs, have many uses in physics; and walks with memory are standard models for a number of phenomena. We study persistent quantum walks, and compare them with equivalent classical Markov processes. The first question to ask is how the mixing time compares between persistent quantum and classical walks. Since quantum walks are generated by unitary matrices, they do not converge to a stationary state. The mixing time is then naturally introduced via a limiting distribution defined as the average of the probability distributions over time (Cesaro sum). We compare the mixing times, along with other properties, using numerical methods and spectral analysis. Our preliminary results indicate a significant speedup in some cases, and a number of other interesting aspects of quantum walks.

  13. Complex Classical Mechanics of a QES Potential

    NASA Astrophysics Data System (ADS)

    Bhabani Prasad, Mandal; Sushant, S. Mahajan

    2015-10-01

    We study a combined parity (P) and time reversal (T) invariant non-Hermitian quasi-exactly solvable (QES) potential, which exhibits PT phase transition, in the complex plane classically to demonstrate different quantum effects. The particle with real energy makes closed orbits around one of the periodic wells of the complex potential depending on the initial condition. However interestingly the particle escapes to an open orbits even with real energy if it is placed beyond a certain distance from the center of the well. On the other hand when the particle energy is complex the trajectory is open and the particle tunnels back and forth between two wells which are separated by a classically forbidden path. The tunneling time is calculated for different pair of wells and is shown to vary inversely with the imaginary component of energy. Our study reveals that spontaneous PT symmetry breaking does not affect the qualitative features of the particle trajectories in the analogous complex classical model. Support from Department of Science and Technology (DST), Govt. of India under SERC Project Sanction Grant No. SR/S2/HEP-0009/2012

  14. FSH isoform pattern in classic galactosemia.

    PubMed

    Gubbels, Cynthia S; Thomas, Chris M G; Wodzig, Will K W H; Olthaar, André J; Jaeken, Jaak; Sweep, Fred C G J; Rubio-Gozalbo, M Estela

    2011-04-01

    Female classic galactosemia patients suffer from primary ovarian insufficiency (POI). The cause for this long-term complication is not fully understood. One of the proposed mechanisms is that hypoglycosylation of complex molecules, a known secondary phenomenon of galactosemia, leads to FSH dysfunction. An earlier study showed less acidic isoforms of FSH in serum samples of two classic galactosemia patients compared to controls, indicating hypoglycosylation. In this study, FSH isoform patterns of five classic galactosemia patients with POI were compared to the pattern obtained in two patients with a primary glycosylation disorder (phosphomannomutase-2-deficient congenital disorders of glycosylation, PMM2-CDG) and POI, and in five postmenopausal women as controls. We used FPLC chromatofocussing with measurement of FSH concentration per fraction, and discovered that there were no significant differences between galactosemia patients, PMM2-CDG patients and postmenopausal controls. Our results do not support that FSH dysfunction due to a less acidic isoform pattern because of hypoglycosylation is a key mechanism of POI in this disease.

  15. Mesoscopic systems: classical irreversibility and quantum coherence.

    PubMed

    Barbara, Bernard

    2012-09-28

    Mesoscopic physics is a sub-discipline of condensed-matter physics that focuses on the properties of solids in a size range intermediate between bulk matter and individual atoms. In particular, it is characteristic of a domain where a certain number of interacting objects can easily be tuned between classical and quantum regimes, thus enabling studies at the border of the two. In magnetism, such a tuning was first realized with large-spin magnetic molecules called single-molecule magnets (SMMs) with archetype Mn(12)-ac. In general, the mesoscopic scale can be relatively large (e.g. micrometre-sized superconducting circuits), but, in magnetism, it is much smaller and can reach the atomic scale with rare earth (RE) ions. In all cases, it is shown how quantum relaxation can drastically reduce classical irreversibility. Taking the example of mesoscopic spin systems, the origin of irreversibility is discussed on the basis of the Landau-Zener model. A classical counterpart of this model is described enabling, in particular, intuitive understanding of most aspects of quantum spin dynamics. The spin dynamics of mesoscopic spin systems (SMM or RE systems) becomes coherent if they are well isolated. The study of the damping of their Rabi oscillations gives access to most relevant decoherence mechanisms by different environmental baths, including the electromagnetic bath of microwave excitation. This type of decoherence, clearly seen with spin systems, is easily recovered in quantum simulations. It is also observed with other types of qubits such as a single spin in a quantum dot or a superconducting loop, despite the presence of other competitive decoherence mechanisms. As in the molecular magnet V(15), the leading decoherence terms of superconducting qubits seem to be associated with a non-Markovian channel in which short-living entanglements with distributions of two-level systems (nuclear spins, impurity spins and/or charges) leading to 1/f noise induce τ(1)-like

  16. Gauge-fields and integrated quantum-classical theory

    SciTech Connect

    Stapp, H.P.

    1986-01-01

    Physical situations in which quantum systems communicate continuously to their classically described environment are not covered by contemporary quantum theory, which requires a temporary separation of quantum degrees of freedom from classical ones. A generalization would be needed to cover these situations. An incomplete proposal is advanced for combining the quantum and classical degrees of freedom into a unified objective description. It is based on the use of certain quantum-classical structures of light that arise from gauge invariance to coordinate the quantum and classical degrees of freedom. Also discussed is the question of where experimenters should look to find phenomena pertaining to the quantum-classical connection. 17 refs.

  17. Statistical mechanics of quantum-classical systems with holonomic constraints.

    PubMed

    Sergi, Alessandro

    2006-01-14

    The statistical mechanics of quantum-classical systems with holonomic constraints is formulated rigorously by unifying the classical Dirac bracket and the quantum-classical bracket in matrix form. The resulting Dirac quantum-classical theory, which conserves the holonomic constraints exactly, is then used to formulate time evolution and statistical mechanics. The correct momentum-jump approximation for constrained systems arises naturally from this formalism. Finally, in analogy with what was found in the classical case, it is shown that the rigorous linear-response function of constrained quantum-classical systems contains nontrivial additional terms which are absent in the response of unconstrained systems.

  18. NUCLEAR MIXING METERS FOR CLASSICAL NOVAE

    SciTech Connect

    Kelly, Keegan J.; Iliadis, Christian; Downen, Lori; Champagne, Art; José, Jordi

    2013-11-10

    Classical novae are caused by mass transfer episodes from a main-sequence star onto a white dwarf via Roche lobe overflow. This material possesses angular momentum and forms an accretion disk around the white dwarf. Ultimately, a fraction of this material spirals in and piles up on the white dwarf surface under electron-degenerate conditions. The subsequently occurring thermonuclear runaway reaches hundreds of megakelvin and explosively ejects matter into the interstellar medium. The exact peak temperature strongly depends on the underlying white dwarf mass, the accreted mass and metallicity, and the initial white dwarf luminosity. Observations of elemental abundance enrichments in these classical nova events imply that the ejected matter consists not only of processed solar material from the main-sequence partner but also of material from the outer layers of the underlying white dwarf. This indicates that white dwarf and accreted matter mix prior to the thermonuclear runaway. The processes by which this mixing occurs require further investigation to be understood. In this work, we analyze elemental abundances ejected from hydrodynamic nova models in search of elemental abundance ratios that are useful indicators of the total amount of mixing. We identify the abundance ratios ΣCNO/H, Ne/H, Mg/H, Al/H, and Si/H as useful mixing meters in ONe novae. The impact of thermonuclear reaction rate uncertainties on the mixing meters is investigated using Monte Carlo post-processing network calculations with temperature-density evolutions of all mass zones computed by the hydrodynamic models. We find that the current uncertainties in the {sup 30}P(p, γ){sup 31}S rate influence the Si/H abundance ratio, but overall the mixing meters found here are robust against nuclear physics uncertainties. A comparison of our results with observations of ONe novae provides strong constraints for classical nova models.

  19. Meteorological phenomena in Western classical orchestral music

    NASA Astrophysics Data System (ADS)

    Williams, P. D.; Aplin, K. L.

    2012-12-01

    The creative output of composers, writers, and artists is often influenced by their surroundings. To give a literary example, it has been claimed recently that some of the characters in Oliver Twist and A Christmas Carol were based on real-life people who lived near Charles Dickens in London. Of course, an important part of what we see and hear is not only the people with whom we interact, but also our geophysical surroundings. Of all the geophysical phenomena to influence us, the weather is arguably the most significant, because we are exposed to it directly and daily. The weather was a great source of inspiration for Monet, Constable, and Turner, who are known for their scientifically accurate paintings of the skies. But to what extent does weather inspire composers? The authors of this presentation, who are atmospheric scientists by day but amateur classical musicians by night, have been contemplating this question. We have built a systematic musical database, which has allowed us to catalogue and analyze the frequencies with which weather is depicted in a sample of classical orchestral music. The depictions vary from explicit mimicry using traditional and specialized orchestral instruments, through to subtle suggestions. We have found that composers are generally influenced by their own environment in the type of weather they choose to represent. As befits the national stereotype, British composers seem disproportionately keen to depict the UK's variable weather patterns and stormy coastline. Reference: Aplin KL and Williams PD (2011) Meteorological phenomena in Western classical orchestral music. Weather, 66(11), pp 300-306. doi:10.1002/wea.765

  20. Classical Simulated Annealing Using Quantum Analogues

    NASA Astrophysics Data System (ADS)

    La Cour, Brian R.; Troupe, James E.; Mark, Hans M.

    2016-08-01

    In this paper we consider the use of certain classical analogues to quantum tunneling behavior to improve the performance of simulated annealing on a discrete spin system of the general Ising form. Specifically, we consider the use of multiple simultaneous spin flips at each annealing step as an analogue to quantum spin coherence as well as modifications of the Boltzmann acceptance probability to mimic quantum tunneling. We find that the use of multiple spin flips can indeed be advantageous under certain annealing schedules, but only for long anneal times.

  1. TOPICAL REVIEW: Nucleosynthesis in classical nova explosions

    NASA Astrophysics Data System (ADS)

    José, Jordi; Hernanz, Margarita

    2007-12-01

    Classical novae are fascinating stellar explosions at the crossroads of stellar astrophysics, nuclear physics, and cosmochemistry. In this review, we briefly summarize 30 years of nucleosynthesis studies, with special emphasis on recent advances in nova theory (including multidimensional models) as well as on experimental efforts to reduce nuclear uncertainties affecting critical reaction rates. Among the topics that are covered, we outline the interplay between nova outbursts and the galactic chemical abundances, the synthesis of radioactive nuclei of interest for γ-ray astronomy, such as 7Li, 22Na or 26Al, and the potential discovery of presolar meteoritic grains likely condensed in nova shells.

  2. Soliton splitting in quenched classical integrable systems

    NASA Astrophysics Data System (ADS)

    Gamayun, O.; Semenyakin, M.

    2016-08-01

    We take a soliton solution of a classical non-linear integrable equation and quench (suddenly change) its non-linearity parameter. For that we multiply the amplitude or the width of a soliton by a numerical factor η and take the obtained profile as a new initial condition. We find the values of η for which the post-quench solution consists of only a finite number of solitons. The parameters of these solitons are found explicitly. Our approach is based on solving the direct scattering problem analytically. We demonstrate how it works for Korteweg-de Vries, sine-Gordon and non-linear Schrödinger integrable equations.

  3. Classical Antiferromagnetism in Kinetically Frustrated Electronic Models

    NASA Astrophysics Data System (ADS)

    Sposetti, C. N.; Bravo, B.; Trumper, A. E.; Gazza, C. J.; Manuel, L. O.

    2014-05-01

    We study, by means of the density matrix renormalization group, the infinite U Hubbard model—with one hole doped away from half filling—in triangular and square lattices with frustrated hoppings, which invalidate Nagaoka's theorem. We find that these kinetically frustrated models have antiferromagnetic ground states with classical local magnetization in the thermodynamic limit. We identify the mechanism of this kinetic antiferromagnetism with the release of the kinetic energy frustration, as the hole moves in the established antiferromagnetic background. This release can occur in two different ways: by a nontrivial spin Berry phase acquired by the hole, or by the effective vanishing of the hopping amplitude along the frustrating loops.

  4. Classical light beams and geometric phases.

    PubMed

    Mukunda, N; Chaturvedi, S; Simon, R

    2014-06-01

    We present a study of geometric phases in classical wave and polarization optics using the basic mathematical framework of quantum mechanics. Important physical situations taken from scalar wave optics, pure polarization optics, and the behavior of polarization in the eikonal or ray limit of Maxwell's equations in a transparent medium are considered. The case of a beam of light whose propagation direction and polarization state are both subject to change is dealt with, attention being paid to the validity of Maxwell's equations at all stages. Global topological aspects of the space of all propagation directions are discussed using elementary group theoretical ideas, and the effects on geometric phases are elucidated.

  5. Classical dynamics of free electromagnetic laser pulses

    NASA Astrophysics Data System (ADS)

    Goto, S.; Tucker, R. W.; Walton, T. J.

    2016-02-01

    We discuss a class of exact finite energy solutions to the vacuum source-free Maxwell field equations as models for multi- and single cycle laser pulses in classical interaction with relativistic charged test particles. These solutions are classified in terms of their chiral content based on their influence on particular charge configurations in space. Such solutions offer a computationally efficient parameterization of compact laser pulses used in laser-matter simulations and provide a potential means for experimentally bounding the fundamental length scale in the generalized electrodynamics of Bopp, Landé and Podolsky.

  6. Revisiting the Classics in Childbirth Education

    PubMed Central

    Shilling, Teri; Bingham, Stacie

    2010-01-01

    In celebration of Lamaze International's 50th anniversary, reviewers share their thoughts on some classic Lamaze resource materials and how their content relates to today's viewpoints on birth and childbirth education. Although some of the material may be outdated, all of the resources offer timeless insights as well as a unique view on the history of childbirth education. The following topics are addressed: past cultural views of birth; advocacy for change in birth practices; Lamaze method; pioneers in childbirth; importance of childbirth education; and birth advocacy. PMID:21629386

  7. Selected Studies in Classical and Quantum Gravity

    NASA Astrophysics Data System (ADS)

    Saotome, Ryo

    This thesis is composed of two parts, one corresponding to classical and the other to quantum gravitational phenomena. In the classical part, we focus on the behavior of various classical scalar fields in the presence of black holes. New fundamental results discussed include the first confirmation of the Belinskii, Khalatnikov, and Lifschitz (BKL) conjecture for an asymptotically flat spacetime, where we find that the dynamics of a canonical test scalar field near a black hole singularity are dominated by terms with time derivatives. We also perform a numerical simulation of the gravitational collapse of a non-canonical scalar field showing that signals can escape black holes in the k-essence dark energy model and find numerical confirmation that the accretion of various scalar fields onto a black hole from generic initial conditions is stationary. In the second part, we focus on the long distance behavior of perturbative quantum gravity. New results discussed include a proof of the cancellation of collinear divergences to all orders in the amplitudes of the theory as well as a characterization of all infrared divergent diagrams. In particular, we find that the only diagrams that can have soft divergences are ladder and crossed ladder diagrams, and that the only collinearly divergent diagrams are those with only three point vertices and no internal jet loops. Also presented is a construction of a double copy relation between gravity and gauge theory amplitudes similar to that conjectured by Bern, Carrasco, and Johansson for the case where there is no hard momentum exchange in the scattering, which we find implies a squaring relation between the classical shockwave solutions of the two theories as well. Finally, the first calculation of a gravitational scattering amplitude through the next-to-leading eikonal order is performed. We find that this correction to the scattering amplitude exponentiates, and that these power corrections probe smaller impact parameters

  8. Covariant change of signature in classical relativity

    NASA Astrophysics Data System (ADS)

    Ellis, G. F. R.

    1992-10-01

    This paper gives a covariant formalism enabling investigation of the possibility of change of signature in classical General Relativity, when the geometry is that of a Robertson-Walker universe. It is shown that such changes are compatible with the Einstein field equations, both in the case of a barotropic fluid and of a scalar field. A criterion is given for when such a change of signature should take place in the scalar field case. Some examples show the kind of resulting exact solutions of the field equations.

  9. Classical problems in computational aero-acoustics

    NASA Technical Reports Server (NTRS)

    Hardin, Jay C.

    1996-01-01

    In relation to the expected problems in the development of computational aeroacoustics (CAA), the preliminary applications were to classical problems where the known analytical solutions could be used to validate the numerical results. Such comparisons were used to overcome the numerical problems inherent in these calculations. Comparisons were made between the various numerical approaches to the problems such as direct simulations, acoustic analogies and acoustic/viscous splitting techniques. The aim was to demonstrate the applicability of CAA as a tool in the same class as computational fluid dynamics. The scattering problems that occur are considered and simple sources are discussed.

  10. Hybridizing matter-wave and classical accelerometers

    SciTech Connect

    Lautier, J.; Volodimer, L.; Hardin, T.; Merlet, S.; Lours, M.; Pereira Dos Santos, F.; Landragin, A.

    2014-10-06

    We demonstrate a hybrid accelerometer that benefits from the advantages of both conventional and atomic sensors in terms of bandwidth (DC to 430 Hz) and long term stability. First, the use of a real time correction of the atom interferometer phase by the signal from the classical accelerometer enables to run it at best performance without any isolation platform. Second, a servo-lock of the DC component of the conventional sensor output signal by the atomic one realizes a hybrid sensor. This method paves the way for applications in geophysics and in inertial navigation as it overcomes the main limitation of atomic accelerometers, namely, the dead times between consecutive measurements.

  11. Weak measurements and nonClassical correlations

    NASA Astrophysics Data System (ADS)

    Lekshmi, S.; Shaji, N.; Shaji, Anil

    2017-01-01

    We extend the definition of quantum discord as a quantifier of nonClassical correlations in a quantum state to the case where weak measurements are performed on subsystem A of a bipartite system AB. The properties of weak discord are explored for several families of quantum states. We find that in many cases weak quantum discord is identical to normal discord and in general the values of the two are very close to each other. Weak quantum discord reduces to discord in the appropriate limits as well. We also discuss the implications of these observations on the interpretations of quantum discord.

  12. Bohmian trajectory from the "classical" Schrödinger equation.

    PubMed

    Sengupta, Santanu; Khatua, Munmun; Chattaraj, Pratim Kumar

    2014-12-01

    The quantum-classical correspondence is studied for a periodically driven quartic oscillator exhibiting integrable and chaotic dynamics, by studying the Bohmian trajectory of the corresponding "classical" Schrödinger equation. Phase plots and the Kolmogorov-Sinai entropy are computed and compared with the classical trajectory as well as the Bohmian trajectory obtained from the time dependent Schrödinger equation. Bohmian mechanics at the classical limit appears to mimick the behavior of a dissipative dynamical system.

  13. Classical and nonclassical randomness in quantum measurements

    NASA Astrophysics Data System (ADS)

    Farenick, Douglas; Plosker, Sarah; Smith, Jerrod

    2011-12-01

    The space POVM_H(X) of positive operator-valued probability measures on the Borel sets of a compact (or even locally compact) Hausdorff space X with values in B(H), the algebra of linear operators acting on a d-dimensional Hilbert space H, is studied from the perspectives of classical and nonclassical convexity through a transform Γ that associates any positive operator-valued measure ν with a certain completely positive linear map Γ(ν) of the homogeneous C*-algebra C(X)⊗ B(H) into B(H). This association is achieved by using an operator-valued integral in which nonclassical random variables (that is, operator-valued functions) are integrated with respect to positive operator-valued measures and which has the feature that the integral of a random quantum effect is itself a quantum effect. A left inverse Ω for Γ yields an integral representation, along the lines of the classical Riesz representation theorem for linear functionals on C(X), of certain (but not all) unital completely positive linear maps φ :C(X)⊗ B(H)rArr B(H). The extremal and C*-extremal points of POVM_H(X) are determined.

  14. Extending classical molecular theory with polarization.

    PubMed

    Keyes, Tom; Napoleon, Raeanne L

    2011-01-27

    A classical, polarizable, electrostatic theory of short-ranged atom-atom interactions, incorporating the smeared nature of atomic partial charges, is presented. Detailed models are constructed for CO monomer and for CO interacting with an iron atom, as a first step toward heme proteins. A good representation is obtained of the bond-length-dependent dipole of CO monomer from fitting at the equilibrium distance only. Essential features of the binding of CO to myoglobin (Mb) and model heme compounds, including the binding energy, the position of the minimum in the Fe-C potential, the Fe-C frequency, the bending energy, the linear geometry of FeCO, and the increase of the Stark tuning rate and IR intensity, are obtained, suggesting that a substantial part of the Fe-CO interaction consists of a classical, noncovalent, "electrostatic bond ". The binding energy is primarily polarization energy, and the polarization energy of an OH pair in water is shown to be comparable to the experimental hydrogen bond energy.

  15. Simple improvements to classical bubble nucleation models

    NASA Astrophysics Data System (ADS)

    Tanaka, Kyoko K.; Tanaka, Hidekazu; Angélil, Raymond; Diemand, Jürg

    2015-08-01

    We revisit classical nucleation theory (CNT) for the homogeneous bubble nucleation rate and improve the classical formula using a correct prefactor in the nucleation rate. Most of the previous theoretical studies have used the constant prefactor determined by the bubble growth due to the evaporation process from the bubble surface. However, the growth of bubbles is also regulated by the thermal conduction, the viscosity, and the inertia of liquid motion. These effects can decrease the prefactor significantly, especially when the liquid pressure is much smaller than the equilibrium one. The deviation in the nucleation rate between the improved formula and the CNT can be as large as several orders of magnitude. Our improved, accurate prefactor and recent advances in molecular dynamics simulations and laboratory experiments for argon bubble nucleation enable us to precisely constrain the free energy barrier for bubble nucleation. Assuming the correction to the CNT free energy is of the functional form suggested by Tolman, the precise evaluations of the free energy barriers suggest the Tolman length is ≃0.3 σ independently of the temperature for argon bubble nucleation, where σ is the unit length of the Lennard-Jones potential. With this Tolman correction and our prefactor one gets accurate bubble nucleation rate predictions in the parameter range probed by current experiments and molecular dynamics simulations.

  16. Classical and quantum routes to linear magnetoresistance

    NASA Astrophysics Data System (ADS)

    Hu, Jingshi

    The transverse, positive magnetoresistance of suitably doped silver chalcogenides and indium antimonides changes linearly with magnetic field by thousands of percent, with no sign of saturation up to MegaGauss. A precise characterization of these unexpected observations has led to two very different, yet equally interesting magnetotransport mechanisms: the classical inhomogeneity-induced current jetting, and quantum linear magnetoresistance. The inhomogeneous distribution of excess/deficient silver atoms lies behind the anomalous magnetoresistive response of silver chalcogenides, introducing spatial conductivity fluctuations with length scales independent of the cyclotron radius. We show that a systematic investigation of the resistivity tensor in longitudinal field could be used to identify the spatial inhomogeneities and determine the associated length scale of the current distortion. By contrast, the linear magnetoresistance observed in single-crystalline InSb presents a spectacular manifestation of magnetotransport in the extreme quantum limit, when only one Landau band is partially filled. Harnessing both the classical and quantum effects opens the gate to artificial fabrication of conducting networks with micron scale unit size for enhanced magnetoresistive sensitivity.

  17. Will the digital computer transform classical mathematics?

    PubMed

    Rotman, Brian

    2003-08-15

    Mathematics and machines have influenced each other for millennia. The advent of the digital computer introduced a powerfully new element that promises to transform the relation between them. This paper outlines the thesis that the effect of the digital computer on mathematics, already widespread, is likely to be radical and far-reaching. To articulate this claim, an abstract model of doing mathematics is introduced based on a triad of actors of which one, the 'agent', corresponds to the function performed by the computer. The model is used to frame two sorts of transformation. The first is pragmatic and involves the alterations and progressive colonization of the content and methods of enquiry of various mathematical fields brought about by digital methods. The second is conceptual and concerns a fundamental antagonism between the infinity enshrined in classical mathematics and physics (continuity, real numbers, asymptotic definitions) and the inherently real and material limit of processes associated with digital computation. An example which lies in the intersection of classical mathematics and computer science, the P=NP problem, is analysed in the light of this latter issue.

  18. Ehlers-Danlos syndrome, classical type.

    PubMed

    Bowen, Jessica M; Sobey, Glenda J; Burrows, Nigel P; Colombi, Marina; Lavallee, Mark E; Malfait, Fransiska; Francomano, Clair A

    2017-02-13

    Classical EDS is a heritable disorder of connective tissue. Patients are affected with joint hypermobility, skin hyperextensibilty, and skin fragility leading to atrophic scarring and significant bruising. These clinical features suggest consideration of the diagnosis which then needs to be confirmed, preferably by genetic testing. The most recent criteria for the diagnosis of EDS were devised in Villefranche in 1997. [Beighton et al. (1998); Am J Med Genet 77:31-37]. The aims set out in the Villefranche Criteria were: to enable diagnostic uniformity for clinical and research purposes, to understand the natural history of each subtype of EDS, to inform management and genetic counselling, and to identify potential areas of research. The authors recognized that the criteria would need updating, but viewed the Villefranche nosology as a good starting point. Since 1997, there have been major advances in the molecular understanding of classical EDS. Previous question marks over genetic heterogeneity have been largely surpassed by evidence that abnormalities in type V collagen are the cause. Advances in molecular testing have made it possible to identify the causative mutation in the majority of patients. This has aided the further clarification of this diagnosis. The aim of this literature review is to summarize the current knowledge and highlight areas for future research. © 2017 Wiley Periodicals, Inc.

  19. Robust topological degeneracy of classical theories

    NASA Astrophysics Data System (ADS)

    Vaezi, Mohammad-Sadegh; Ortiz, Gerardo; Nussinov, Zohar

    2016-05-01

    We challenge the hypothesis that the ground states of a physical system whose degeneracy depends on topology must necessarily realize topological quantum order and display nonlocal entanglement. To this end, we introduce and study a classical rendition of the Toric Code model embedded on Riemann surfaces of different genus numbers. We find that the minimal ground state degeneracy (and those of all levels) depends on the topology of the embedding surface alone. As the ground states of this classical system may be distinguished by local measurements, a characteristic of Landau orders, this example illustrates that topological degeneracy is not a sufficient condition for topological quantum order. This conclusion is generic and, as shown, it applies to many other models. We also demonstrate that certain lattice realizations of these models, and other theories, display a ground state entropy (and those of all levels) that is "holographic", i.e., extensive in the system boundary. We find that clock and U (1 ) gauge theories display topological (in addition to gauge) degeneracies.

  20. The structure of the classical cosmological singularity

    NASA Astrophysics Data System (ADS)

    Tipler, Frank J.

    The existence of an all-encompassing initial classical cosmological singularity is established: it is shown that if: (1) global hyperbolicity, (2) the timelike convergence condition, and (3) all past-directed nonspacelike geodesics start to reconverge within a compact region in the causal past of the present-day earth, then all timelike curves in the past have a finite proper time length less than a universal constant L. It is argued that an analogue of this predicted cosmological singularity should exist even when quantum effects are taken into account. In particular, in a closed Friedmann radiation-filled universe quantized via the ADM method, the R = 0 singularity still exists and influences wave packet evolution at all times. Furthermore, quantum effects can in most cases eliminate curvature singularities only by introducing singularities in the universal action; most classical closed universes have finite action if and only if they begin and end in curvature singularities. Finally, the two basic ways of studying the structure of cosmological singularities are reviewed: completion methods (e.g., the c-boundary construction), and approach methods (e.g., analyzing metric behavior in a synchronous coordinate system).

  1. Non-classical types of loess

    NASA Astrophysics Data System (ADS)

    Iriondo, M. H.; Kröhling, D. M.

    2007-12-01

    The purpose of this contribution is to describe the sequence of physical and chemical processes resulting in the sediment-type named loess, a fine-grained sediment deposit of universal occurrence. Owing to historical causes, loess has been (and still is) implicitly linked to glacial/periglacial environments among most naturalists. However it is known today that most eolian dust is deflated from tropical deserts. Hence, that sequence of processes is more comprehensive than the former narrow cold scenario. Six examples of different "non-classical" cases (from South America and Europe) that fit well to the loess definition are developed: 1) volcanic loess in Ecuador: pyroclastic eruptions/valley wind/mountain praire/silica structuring; 2) tropical loess in northeastern Argentina, Brazil and Uruguay: deflation of river and fan splays/savanna/iron sesquioxide structuring; 3) gypsum loess in northern Spain: destruction of anhydrite/gypsiferous layers in a dry climate/valley wind/Saharian shrub peridesert/gypsum structuring; 4) trade-wind deposits in Venezuela and Brazil: deflation in tidal flats/trade wind into the continent/savanna/iron hydroxide structuring; 5) anticyclonic gray loess in Argentina: continental anticyclone on plains/anti-clockwise winds and whirls/steppe/carbonate structuring. All these non-classical types conform to the accepted loess definitions and they also share the most important field characteristics of loess such as grain size, friability, vertical or sub-vertical slopes in outcrops, subfusion and others. Other cases can probably be recognized when systematically scrutinized.

  2. Snow Line Localization in Classical Protoplanetary Disks

    NASA Astrophysics Data System (ADS)

    Blevins, S.

    2014-04-01

    Protoplanetary disks are volatile-rich environments capable of producing the essential conditions that make planet formation viable. Establishing a molecular inventory of dominant volatile species, such as water, in the planet-forming zones surrounding young, solar-type stars elevates our understanding of the chemistry involved with planet formation, composition and disk evolution. For this study we measure the water vapor content and determine the location of the condensation front, or snow line, for four classical disks selected for the strong water emission present in their mid-infrared spectra. To accomplish this we combine deep Herschel PACS observations with high resolution Spitzer IRS spectra to create molecular maps comprised of water lines with excitation temperatures that trace the disks' surfaces from 1-100 AU. We use two-dimensional, axisymmetric radiative transfer modeling to retrieve the disks' dust structures and the RADLite raytracer to render model spectra for each disk. A simple step function is used to define the abundance structure and the model spectra are fit to the observed water lines. Preliminary results will be discussed, including the inner disk chemical content, snow line radius and fractional water vapor abundances for the classical disk RNO 90.

  3. Classical helium atom with radiation reaction.

    PubMed

    Camelio, G; Carati, A; Galgani, L

    2012-06-01

    We study a classical model of helium atom in which, in addition to the Coulomb forces, the radiation reaction forces are taken into account. This modification brings in the model a new qualitative feature of a global character. Indeed, as pointed out by Dirac, in any model of classical electrodynamics of point particles involving radiation reaction one has to eliminate, from the a priori conceivable solutions of the problem, those corresponding to the emission of an infinite amount of energy. We show that the Dirac prescription solves a problem of inconsistency plaguing all available models which neglect radiation reaction, namely, the fact that in all such models, most initial data lead to a spontaneous breakdown of the atom. A further modification is that the system thus acquires a peculiar form of dissipation. In particular, this makes attractive an invariant manifold of special physical interest, the zero-dipole manifold that corresponds to motions in which no energy is radiated away (in the dipole approximation). We finally study numerically the invariant measure naturally induced by the time-evolution on such a manifold, and this corresponds to studying the formation process of the atom. Indications are given that such a measure may be singular with respect to that of Lebesgue.

  4. Mass flux in extended and classical hydrodynamics.

    PubMed

    Grmela, Miroslav

    2014-06-01

    In classical hydrodynamics, the mass flux is universally chosen to be the momentum field. In extended hydrodynamics, the mass flux acquires different terms. The extended hydrodynamics introduced and investigated in this paper uses a one-particle distribution function as the extra state variable chosen to characterize the microstructure. We prove that the extended hydrodynamics is fully autonomous in the sense that it is compatible with thermodynamics (i.e., the entropy does not decrease during the time evolution) and with mechanics (i.e., the part of the time evolution that leaves the entropy unchanged is Hamiltonian). Subsequently, we investigate its possible reductions. In some situations the emerging reduced dynamical theory is the classical hydrodynamics that is fully autonomous (i.e., all the structure that makes the extended theory fully autonomous is kept in the reduced theory). In other situations (for example, when the fluids under investigation have large density gradients) the reduced theories are not fully autonomous. In such a case the reduced theories constitute a family of mutually related dynamical theories (each of them involving a different amount of detail) that we consider to be a mathematical formulation of multiscale (or multilevel) hydrodynamics. It is in the reduced theories belonging to the multiscale hydrodynamics where the terms that emerge in the mass flux take the form of self-diffusion.

  5. Evidence of In Utero Transmission of Classical Scrapie in Sheep

    PubMed Central

    Hawkins, Stephen A. C.; Simmons, Marion M.; Bellworthy, Susan J.

    2014-01-01

    Classical scrapie is one of the transmissible spongiform encephalopathies (TSEs), a group of fatal infectious diseases that affect the central nervous system (CNS). Classical scrapie can transmit laterally from ewe to lamb perinatally or between adult animals. Here we report detection of infectivity in tissues of an unborn fetus, providing evidence that in utero transmission of classical scrapie is also possible. PMID:24453368

  6. Classical Influence on the Founding of the American Republic.

    ERIC Educational Resources Information Center

    Molanphy, Helen M.

    The founding fathers of the United States were products of a classical education, and they used the Greek and Roman classics as republican models and classical virtues. In their writings, the founders frequently associated liberty and republicanism with the ancient commonwealths. John Adams spoke on three separate occasions of the need to reflect…

  7. Evidence of in utero transmission of classical scrapie in sheep.

    PubMed

    Spiropoulos, John; Hawkins, Stephen A C; Simmons, Marion M; Bellworthy, Susan J

    2014-04-01

    Classical scrapie is one of the transmissible spongiform encephalopathies (TSEs), a group of fatal infectious diseases that affect the central nervous system (CNS). Classical scrapie can transmit laterally from ewe to lamb perinatally or between adult animals. Here we report detection of infectivity in tissues of an unborn fetus, providing evidence that in utero transmission of classical scrapie is also possible.

  8. HST observations of faint Cold Classical KBOs

    NASA Astrophysics Data System (ADS)

    Penteado, Paulo F.; Trilling, David E.; Grundy, Will

    2016-10-01

    The size distribution of the known Kuiper Belt Objects has been described by a double power law, with a break at R magnitude 25. There are two leading interpretations to this break: 1) It is the result of the collisional evolution, with the objects smaller than the break being the population most affected by collisional erosion. 2) The size distribution break is primordial, set during the Kuiper Belt formation.The low inclination KBOs, the Cold Classical population, is thought to have been dynamically isolated since the formation of the Solar System, and thus only collisions between Cold Classicals would have affected their size distribution. If the distribution is collisional, it probes parameters of the Kuiper Belt history: strengths of the bodies, impact energies and frequency, and the the number of objects. If the distribution is primordial, it reveals parameters of the Kuiper Belt accretion, as well as limits on its subsequent collisional history.We obtained HST observations of 16 faint Cold Classicals, which we combine with archival HST observations of 20 others, to examine the distribution of two properties of the smallest KBOs: colors and binary fraction. These properties can differentiate between a primordial and a collisional origin of the size distribution break. If the smaller bodies have been through extensive collisional evolution, they will have exposed materials from their interiors, which has not been exposed to weathering, and thus should be bluer than the old surfaces of the larger bodies. Another constraint can be derived from the fraction of binary objects: the angular momentum of the observed binaries is typically too high to result from collisions, thus a collisionally-evolved population would have a lower binary fraction, due to the easier separation of binaries, compared to the disruption of similar-sized bodies, and the easier disruption of the binary components, due to the smaller size.We present the constraints to the color and binary

  9. Electrocardiographic enigma of a classical disease: pellagra.

    PubMed

    Kavitha, B; Balasubramanian, R; Kumar, Thirumal

    2012-10-01

    Pellagra is caused by a deficiency of niacin. It is endemic in Africa and Asia where the staple diet of the many refugees or displaced people is corn-based and, therefore, nicotinic acid-deficient. It is also frequently seen in developed countries among chronic alcoholics or, occasionally, those suffering from anorexia nervosa. The usual manifestations are diarrhoea, dementia and dermatitis (the 3Ds), which if left untreated may lead to death. Cardiac manifestations and electrocardiographic changes are rarely seen in those suffering from pellagra. We present a case of pellagra in an alcoholic who presented with the classical rash over the upper limbs along with electrocardiographic changes but without any cardiac symptoms, both of which resolved dramatically after he had been given niacin supplements.

  10. Quantum-Classical Hybrid for Information Processing

    NASA Technical Reports Server (NTRS)

    Zak, Michail

    2011-01-01

    Based upon quantum-inspired entanglement in quantum-classical hybrids, a simple algorithm for instantaneous transmissions of non-intentional messages (chosen at random) to remote distances is proposed. The idea is to implement instantaneous transmission of conditional information on remote distances via a quantum-classical hybrid that preserves superposition of random solutions, while allowing one to measure its state variables using classical methods. Such a hybrid system reinforces the advantages, and minimizes the limitations, of both quantum and classical characteristics. Consider n observers, and assume that each of them gets a copy of the system and runs it separately. Although they run identical systems, the outcomes of even synchronized runs may be different because the solutions of these systems are random. However, the global constrain must be satisfied. Therefore, if the observer #1 (the sender) made a measurement of the acceleration v(sub 1) at t =T, then the receiver, by measuring the corresponding acceleration v(sub 1) at t =T, may get a wrong value because the accelerations are random, and only their ratios are deterministic. Obviously, the transmission of this knowledge is instantaneous as soon as the measurements have been performed. In addition to that, the distance between the observers is irrelevant because the x-coordinate does not enter the governing equations. However, the Shannon information transmitted is zero. None of the senders can control the outcomes of their measurements because they are random. The senders cannot transmit intentional messages. Nevertheless, based on the transmitted knowledge, they can coordinate their actions based on conditional information. If the observer #1 knows his own measurements, the measurements of the others can be fully determined. It is important to emphasize that the origin of entanglement of all the observers is the joint probability density that couples their actions. There is no centralized source

  11. Excited State Quantum-Classical Molecular Dynamics

    NASA Astrophysics Data System (ADS)

    Krstic, Predrag

    2005-05-01

    The development of a new theoretical, algorithmic, and computational framework is reported describing the corresponding excited state many-body dynamics by applying multiphysics described by classical equations of motion for nuclei and Hartree-Fock/Multi-Configuration Hartree-Fock and multiresolution techniques for solving the quantum part of the problem (i.e. the motion of the electrons). We primarily have in mind reactive and electron-transition dynamics which involves molecular clusters, containing hundreds of atoms, perturbed by a slow ionic/atomic/molecular projectile, with possible applications in plasma-surface interactions, cluster physics, chemistry and biotechnology. The validation of the developed technique is performed at three-body systems. Application to the transition dynamics in small carbon clusters and hydrocarbons perturbed by slow carbon ions resolves some long-standing issues in the ion-surface interactions in fusion tokamaks.

  12. Monogamy properties of quantum and classical correlations

    SciTech Connect

    Giorgi, Gian Luca

    2011-11-15

    In contrast with entanglement, as measured by concurrence, in general, quantum discord does not possess the property of monogamy; that is, there is no tradeoff between the quantum discord shared by a pair of subsystems and the quantum discord that both of them can share with a third party. Here, we show that, as far as monogamy is considered, quantum discord of pure states is equivalent to the entanglement of formation. This result allows one to analytically prove that none of the pure three-qubit states belonging to the subclass of W states is monogamous. A suitable physical interpretation of the meaning of the correlation information as a quantifier of monogamy for the total information is also given. Finally, we prove that, for rank 2 two-qubit states, discord and classical correlations are bounded from above by single-qubit von Neumann entropies.

  13. Relativistic like structure of classical thermodynamics

    NASA Astrophysics Data System (ADS)

    Quevedo, Hernando; Sánchez, Alberto; Vázquez, Alejandro

    2015-04-01

    We analyze in the context of geometrothermodynamics a Legendre invariant metric structure in the equilibrium space of an ideal gas. We introduce the concept of thermodynamic geodesic as a succession of points, each corresponding to a state of equilibrium, so that the resulting curve represents a quasi-static process. A rigorous geometric structure is derived in which the thermodynamic geodesics at a given point split the equilibrium space into two disconnected regions separated by adiabatic geodesics. This resembles the causal structure of special relativity, which we use to introduce the concept of adiabatic cone for thermodynamic systems. This result might be interpreted as an alternative indication of the inter-relationship between relativistic physics and classical thermodynamics.

  14. Innovations in classical hormonal targets for endometriosis.

    PubMed

    Pluchino, Nicola; Freschi, Letizia; Wenger, Jean-Marie; Streuli, Isabelle

    2016-01-01

    Endometriosis is a chronic disease of unknown etiology that affects approximately 10% of women in reproductive age. Several evidences show that endometriosis lesions are associated to hormonal imbalance, including estrogen synthesis, metabolism and responsiveness and progesterone resistance. These hormonal alterations influence the ability of endometrial cells to proliferate, migrate and to infiltrate the mesothelium, causing inflammation, pain and infertility. Hormonal imbalance in endometriosis represents also a target for treatment. We provide an overview on therapeutic strategies based on innovations of classical hormonal mechanisms involved in the development of endometriosis lesions. The development phase of new molecules targeting these pathways is also discussed. Endometriosis is a chronic disease involving young women and additional biological targets of estrogen and progesterone pharmacological manipulation (brain, bone and cardiovascular tissue) need to be carefully considered in order to improve and overcome current limits of long-term medical management of endometriosis.

  15. Quantum and classical dynamics in adiabatic computation

    NASA Astrophysics Data System (ADS)

    Crowley, P. J. D.; Äńurić, T.; Vinci, W.; Warburton, P. A.; Green, A. G.

    2014-10-01

    Adiabatic transport provides a powerful way to manipulate quantum states. By preparing a system in a readily initialized state and then slowly changing its Hamiltonian, one may achieve quantum states that would otherwise be inaccessible. Moreover, a judicious choice of final Hamiltonian whose ground state encodes the solution to a problem allows adiabatic transport to be used for universal quantum computation. However, the dephasing effects of the environment limit the quantum correlations that an open system can support and degrade the power of such adiabatic computation. We quantify this effect by allowing the system to evolve over a restricted set of quantum states, providing a link between physically inspired classical optimization algorithms and quantum adiabatic optimization. This perspective allows us to develop benchmarks to bound the quantum correlations harnessed by an adiabatic computation. We apply these to the D-Wave Vesuvius machine with revealing—though inconclusive—results.

  16. Theory of the classical electron gas

    NASA Technical Reports Server (NTRS)

    Guernsey, R. L.

    1978-01-01

    In a previous paper Cohen and Murphy (1969) used the Meeron resummation (1958) of the Mayer diagrams (1950) to calculate the pair correlation for the classical electron gas in thermal equilibrium. They found that successive terms in the expression for the pair correlation were more and more singular for small interparticle spacing, actually dominating the Debye-Hueckel result for sufficiently small distances. This led to apparent divergence in the higher order contributions to the internal energy. The present paper shows that the apparent anomalies in the Cohen-Murphy results can be removed without further resummation by a more careful treatment of the region of small interparticle spacing. It is shown that there is really no anomalous behavior at short range in any order and all integrals in the expression for the internal energy converge.

  17. Respiratory kinematics in classical (opera) singers.

    PubMed

    Watson, P J; Hixon, T J

    1985-03-01

    Anteroposterior diameter changes of the rib cage and abdomen were recorded during respiratory, speaking, and singing activities in six adult male subjects, all baritones with extensive classical singing training and performance experience. Data were charted to solve for lung volume, volume displacements of the rib cage and abdomen, and inferred muscular mechanisms. Separate major roles were inferred for different parts of the respiratory apparatus in the singing process. The abdomen served as a posturing element that mechanically tuned the diaphragm and rib cage to optimal configurations for performance. The rib cage operated as a pressure-flow generating element that regulated expiratory drive. And, the diaphragm functioned as an inspiratory element devoted to reinflating the lungs. Subjects' descriptions of how they thought they breathed during singing bore little correspondence to how they actually breathed. Implications for the training of singers are offered.

  18. Comparing classical and quantum PageRanks

    NASA Astrophysics Data System (ADS)

    Loke, T.; Tang, J. W.; Rodriguez, J.; Small, M.; Wang, J. B.

    2017-01-01

    Following recent developments in quantum PageRanking, we present a comparative analysis of discrete-time and continuous-time quantum-walk-based PageRank algorithms. Relative to classical PageRank and to different extents, the quantum measures better highlight secondary hubs and resolve ranking degeneracy among peripheral nodes for all networks we studied in this paper. For the discrete-time case, we investigated the periodic nature of the walker's probability distribution for a wide range of networks and found that the dominant period does not grow with the size of these networks. Based on this observation, we introduce a new quantum measure using the maximum probabilities of the associated walker during the first couple of periods. This is particularly important, since it leads to a quantum PageRanking scheme that is scalable with respect to network size.

  19. Hemophagocytic syndrome in classic dengue Fever.

    PubMed

    Ray, Sayantan; Kundu, Supratip; Saha, Manjari; Chakrabarti, Prantar

    2011-10-01

    A 24-year-old previously healthy girl presented with persistent fever, headache, and jaundice. Rapid-test anti-dengue virus IgM antibody was positive but anti-dengue IgG was nonreactive, which is suggestive of primary dengue infection. There was clinical deterioration during empiric antibiotic and symptomatic therapy. Bone marrow examination demonstrated the presence of hemophagocytosis. Diagnosis of dengue fever with virus-associated hemophagocytic syndrome was made according to the diagnostic criteria of the HLH 2004 protocol of the Histiocyte Society. The patient recovered with corticosteroid therapy. A review of literature revealed only a handful of case reports that showed the evidence that this syndrome is caused by dengue virus. Our patient is an interesting case of hemophagocytic syndrome associated with classic dengue fever and contributes an additional case to the existing literature on this topic. This case highlights the need for increased awareness even in infections not typically associated with hemophagocytic syndrome.

  20. Classical least squares multivariate spectral analysis

    DOEpatents

    Haaland, David M.

    2002-01-01

    An improved classical least squares multivariate spectral analysis method that adds spectral shapes describing non-calibrated components and system effects (other than baseline corrections) present in the analyzed mixture to the prediction phase of the method. These improvements decrease or eliminate many of the restrictions to the CLS-type methods and greatly extend their capabilities, accuracy, and precision. One new application of PACLS includes the ability to accurately predict unknown sample concentrations when new unmodeled spectral components are present in the unknown samples. Other applications of PACLS include the incorporation of spectrometer drift into the quantitative multivariate model and the maintenance of a calibration on a drifting spectrometer. Finally, the ability of PACLS to transfer a multivariate model between spectrometers is demonstrated.

  1. All Bright Cold Classical KBOs are Binary

    NASA Astrophysics Data System (ADS)

    Noll, Keith S.; Parker, Alex H.; Grundy, William M.

    2014-11-01

    When sorted by absolute magnitude as seen in ground based observations, an extremely high fraction of the brightest Cold Classical (CC) Kuiper Belt objects (KBO) are, in fact resolved as binaries when observed at higher angular resolution. Of the 22 CCs brighter than H=6.1 observed by HST, 16 have been found to be binary yielding a binary fraction of 73±10%. When low inclination interlopers from the hot population and close binaries are considered, this very high fraction is consistent with 100% of bright CCs being binary. At fainter absolute magnitudes, this fraction drops to ~20%. Such a situation is a natural outcome of a broken size distribution with a steep drop-off in the number of CCs with individual component diameters larger than 150 km (for an assumed albedo of 0.15). A sharp cutoff in the size distribution for CCs is consistent with formation models that suggest that most planetesimals form at a preferred modal size of order 100 km.The very high fraction of binaries among the largest CCs also serves to limit the separation distribution of KBO binaries. At most, 27% of the brightest CCs are possible unresolved binaries. The apparent power law distribution of binary separation must cut off near the current observational limits of HST ( 1800 km at 43 AU). It is worth noting, however, that this observation does not constrain how many components of resolved binaries may themselves be unresolved multiples like 47171 1999 TC36. Finally, it is important to point out that, when sorted by the size of the primary rather than absolute magnitude of the unresolved pair, the fraction of binaries is relatively constant with size (Nesvorny et al. 2011, AJ 141, 159) eliminating observational bias as cause of the pile up of binaries among the brightest Cold Classical Kuiper Belt objects.The very high fraction of binaries among the brightest CCs appears to be an effect of the underlying CC size distribution.

  2. On the Classical Schrödinger Equation

    NASA Astrophysics Data System (ADS)

    Benseny, Albert; Tena, David; Oriols, Xavier

    2016-10-01

    In this paper, the classical Schrödinger equation (CSE), which allows the study of classical dynamics in terms of wave functions, is analyzed theoretically and numerically. First, departing from classical (Newtonian) mechanics, and assuming an additional single-valued condition for the Hamilton’s principal function, the CSE is obtained. This additional assumption implies inherent non-classical features on the description of the dynamics obtained from the CSE: the trajectories do not cross in the configuration space. Second, departing from Bohmian mechanics and invoking the quantum-to-classical transition, the CSE is obtained in a natural way for the center of mass of a quantum system with a large number of identical particles. This quantum development imposes the condition of dealing with a narrow wave packet, which implicitly avoids the non-classical features mentioned above. We illustrate all the above points with numerical simulations of the classical and quantum Schrödinger equations for different systems.

  3. Classical chaos and its correspondence in superconducting qubits

    NASA Astrophysics Data System (ADS)

    Neill, C.; Campbell, B.; Chen, Z.; Chiaro, B.; Dunsworth, A.; Fang, M.; Hoi, I.; Kelly, J.; Megrant, A.; O'Malley, P.; Quintana, C.; Vainsencher, A.; Wenner, J.; White, T.; Barends, R.; Chen, Yu; Fowler, A.; Jeffrey, E.; Mutus, J.; Roushan, P.; Sank, D.; Martinis, J. M.

    2015-03-01

    Advances in superconducting qubits have made it possible to experimentally investigate quantum-classical correspondence by constructing quantum systems with chaotic classical limits. We study the quantum equivalent of a classical spinning top using three fully coupled qubits that behave as a single spin-3/2 and subject the spin to a sequence of non-linear rotations. The resulting entanglement bears a striking resemblance to the classical phase space, including bifurcation, and suggests that classical chaos manifests itself as quantum entanglement. Studying the orientation of the spin-3/2 reveals that the rotations which generate chaos and entanglement are at the same time the source of disagreement between the quantum and classical trajectories. Our experiment highlights the correspondence between classical non-linear dynamics and interacting quantum systems.

  4. Classic to postclassic in highland central Mexico.

    PubMed

    Dumond, D E; Muller, F

    1972-03-17

    The data and argument we have presented converge on three points. 1) With the decline and abandonment of Teotihuacan by the end of the Metepec phase (Teotihuacan IV), the valleys of Mexico and of Puebla-Tlax-cala witnessed the development of a ceramic culture that was represented, on the one hand, by obvious Teotihuacan derivations in presumably ritual ware and possible Teotihuacan derivations in simpler pottery of red-on-buff, and, on the other hand, by elements that seem to represent a resurgence of Preclassic characteristics. Whether the development is explained through a measure of outside influence or as a local phenomenon, the direct derivation of a substantial portion of the complex from Classic Teotihuacan is unmistakable. This transitional horizon predated the arrival of plumbate tradeware in highland central Mexico. 2) The transitional horizon coincided with (and no doubt was an integral part of) an alteration of Classic settlement patterns so drastic that it must bespeak political disruption. Nevertheless, there is no evidence that the Postclassic center of Tula represented a significant force in the highlands at that time. There is no evidence that the center of Cholula, which may even have been substantially abandoned during the previous period, was able to exert any force at this juncture; it appears more likely that Cholula was largely reoccupied after the abandonment of Teotihuacan. There is no direct evidence of domination by Xochicalco or any other known major foreign center, although some ceramic traits suggest that relatively minor influences may have emanated from Xochicalco; unfortunately, the state of research at that center does not permit a determination at this time. Thus the most reasonable view on the basis of present evidence is that the abandonment of Teotihuacan was not the direct result of the strength of another centralized power, although some outside populations may have been involved in a minor way. Whatever the proximate cause

  5. Immunomodulation of classical and non-classical HLA molecules by ionizing radiation.

    PubMed

    Gallegos, Cristina E; Michelin, Severino; Dubner, Diana; Carosella, Edgardo D

    2016-05-01

    Radiotherapy has been employed for the treatment of oncological patients for nearly a century, and together with surgery and chemotherapy, radiation oncology constitutes one of the three pillars of cancer therapy. Ionizing radiation has complex effects on neoplastic cells and on tumor microenvironment: beyond its action as a direct cytotoxic agent, tumor irradiation triggers a series of alterations in tumoral cells, which includes the de novo synthesis of particular proteins and the up/down-regulation of cell surface molecules. Additionally, ionizing radiation may induce the release of "danger signals" which may, in turn lead to cellular and molecular responses by the immune system. This immunomodulatory action of ionizing radiation highlights the importance of the combined use (radiotherapy plus immunotherapy) for cancer healing. Major histocompatibility complex antigens (also called Human Leukocyte Antigens, HLA in humans) are one of those molecules whose expression is modulated after irradiation. This review summarizes the modulatory properties of ionizing radiation on the expression of HLA class I (classical and non-classical) and class II molecules, with special emphasis in non-classical HLA-I molecules.

  6. The Moon In The Classic Maya World

    NASA Astrophysics Data System (ADS)

    Romano, Giuliano

    During the Classic Period of the Maya civilization (250-900 A.D.) we have many documents in which it is possible to see the interest of this people on the principal lunar phenomena as the phases and the eclipses in particular. On a number of stelae, lintels and many other inscriptions (in Copan, Quirigua, Tikal, etc.), we can see that in correspondence of the dedication date of the monument, the Maya point out the phase of the Moon and its position in a period of six months corresponding to half year of eclipse. In some parts of the Dresda Codex (one of the four original codices of the Maya) we can see some pages in which were indicated the days of the Tzolkin calendar (the religious calendar of 260 days) in which it is possible to observe a lunar or solar eclipse. The periods of 177 or 148 days are allotted in a sequence that corresponds to the exact interval between the eclipses. The accuracy in the observations and in the calculations of the phases of the Moon, also in very old epochs, is an interesting evidence of the fundamental importance of the Moon in the Maya civilisation.

  7. Classical model of bosons and fermions

    NASA Astrophysics Data System (ADS)

    Kaniadakis, G.; Quarati, P.

    1994-06-01

    In a previous work [Phys. Rev. E 48, 4263 (1993)] we have derived a nonlinear one-dimensional kinetic equation for the distribution function of particles obeying an exclusion principle. In the present work, on the same grounds, we extend this kinetics to D-dimensional continuous or discrete space, in order to study the distribution function of particles obeying a generalized exclusion-inclusion Pauli principle (EIP). This exclusion or inclusion principle is introduced into the classical transition rates by means of an inhibition or an enhancement factor, which contains a parameter κ, whose values range between -1 and +1 and can balance the effect of the full or partial validity of EIP. After deriving the kinetic equation we obtain a general expression of the stationary distribution function, depending on the value we give to the parameter κ. When we limit ourselves to Brownian particles, we derive exactly for κ=-1 the Fermi-Dirac (FD) distribution, for κ=0 the Maxwell-Boltzmann distribution, and for κ=1 the Bose-Einstein (BE) distribution. When κ assumes an intermediate value, except zero, between the extreme values -1 and +1, we obtain statistical distributions different from the FD and BE ones. We attribute to the parameter κ the meaning of the degree of indistinguishability of identical particles, the degree of antisymmetrization, or the symmetrization of the wave function of the particle system.

  8. Pembrolizumab in classical Hodgkin’s lymphoma

    PubMed Central

    Maly, Joseph; Alinari, Lapo

    2016-01-01

    Pembrolizumab is a humanized monoclonal antibody directed against programmed cell death protein 1 (PD-1), a key immune-inhibitory molecule expressed on T cells and implicated in CD4+ T-cell exhaustion and tumor immune-escape mechanisms. Classical Hodgkin’s lymphoma (cHL) is a unique B-cell malignancy in the sense that malignant Reed–Sternberg (RS) cells represent a small percentage of cells within an extensive immune cell infiltrate. PD-1 ligands are upregulated on RS cells as a consequence of both chromosome 9p24.1 amplification and Epstein–Barr virus infection and by interacting with PD-1 promote an immune-suppressive effect. By augmenting antitumor immune response, pembrolizumab and nivolumab, another monoclonal antibody against PD-1, have shown significant activity in patients with relapsed/refractory cHL as well as an acceptable toxicity profile with immune-related adverse events that are generally manageable. In this review, we explore the rationale for targeting PD-1 in cHL, review the clinical trial results supporting the use of checkpoint inhibitors in this disease, and present future directions for investigation in which this approach may be used. PMID:27147112

  9. An approximate classical unimolecular reaction rate theory

    NASA Astrophysics Data System (ADS)

    Zhao, Meishan; Rice, Stuart A.

    1992-05-01

    We describe a classical theory of unimolecular reaction rate which is derived from the analysis of Davis and Gray by use of simplifying approximations. These approximations concern the calculation of the locations of, and the fluxes of phase points across, the bottlenecks to fragmentation and to intramolecular energy transfer. The bottleneck to fragment separation is represented as a vibration-rotation state dependent separatrix, which approximation is similar to but extends and improves the approximations for the separatrix introduced by Gray, Rice, and Davis and by Zhao and Rice. The novel feature in our analysis is the representation of the bottlenecks to intramolecular energy transfer as dividing surfaces in phase space; the locations of these dividing surfaces are determined by the same conditions as locate the remnants of robust tori with frequency ratios related to the golden mean (in a two degree of freedom system these are the cantori). The flux of phase points across each dividing surface is calculated with an analytic representation instead of a stroboscopic mapping. The rate of unimolecular reaction is identified with the net rate at which phase points escape from the region of quasiperiodic bounded motion to the region of free fragment motion by consecutively crossing the dividing surfaces for intramolecular energy exchange and the separatrix. This new theory generates predictions of the rates of predissociation of the van der Waals molecules HeI2, NeI2 and ArI2 which are in very good agreement with available experimental data.

  10. Idiopathic myelofibrosis associated with classic polyarteritis nodosa.

    PubMed

    Camós, Mireia; Arellano-Rodrigo, Eduardo; Abelló, Deborah; Muntañola, Ana; Ferrer, Ana; Grau, Josep Maria; Cervantes, Francisco

    2003-03-01

    A woman with scleroderma and classic polyarteritis nodosa (PAN) who developed idiopathic myelofibrosis (IM) is reported. The patient presented with a one-year history of weakness, polyarthritis, Raynaud phenomenon, dry cough, and epigastralgia. The diagnosis of scleroderma with visceral involvement was made and treatment with prednisone subsequently started, with good clinical response. Six years later, fever, weight loss, livedo reticularis, and dysesthesias developed. Electromyographic studies were consistent with sensory neuropathy and a sural nerve biopsy yielded the diagnosis of PAN. The patient received cyclophosphamide plus prednisone with a favorable response, but 11 years later she was admitted because of weakness, constitutional symptoms, and abdominal pain due to spleen infarcts. Marked anemia, with aniso-poikilocytosis, tear-drop cells, immature myeloid precursors in the peripheral blood, and an increased serum LDH, was observed and the diagnosis of IM established by bone marrow biopsy. This case represents a new association between IM and an autoimmune disease and supports the hypothesis of an immune basis of IM in some patients.

  11. Models of classical and recurrent novae

    NASA Technical Reports Server (NTRS)

    Friedjung, Michael; Duerbeck, Hilmar W.

    1993-01-01

    The behavior of novae may be divided roughly into two separate stages: quiescence and outburst. However, at closer inspection, both stages cannot be separated. It should be attempted to explain features in both stages with a similar model. Various simple models to explain the observed light and spectral observations during post optical maximum activity are conceivable. In instantaneous ejection models, all or nearly all material is ejected in a time that is short compared with the duration of post optical maximum activity. Instantaneous ejection type 1 models are those where the ejected material is in a fairly thin shell, the thickness of which remains small. In the instantaneous ejection type 2 model ('Hubble Flow'), a thick envelope is ejected instantaneously. This envelope remains thick as different parts have different velocities. Continued ejection models emphasize the importance of winds from the nova after optical maximum. Ejection is supposed to occur from one of the components of the central binary, and one can imagine a general swelling of one of the components, so that something resembling a normal, almost stationary, stellar photosphere is observed after optical maximum. The observed characteristics of recurrent novae in general are rather different from those of classical novae, thus, models for these stars need not be the same.

  12. Classical swine fever in the pygmy hog.

    PubMed

    Barman, N N; Bora, D P; Tiwari, A K; Kataria, R S; Desai, G S; Deka, P J

    2012-12-01

    The pygmy hog is a rare, small and highly endangered mammal belonging to the Suidae family, and it is presently found only in the Assam state of India. While investigating the cause of death of pygmy hogs housed at a conservation centre for captive breeding and research at Basistha, Assam, it was confirmed that they were susceptible to and died as a result of contracting classical swine fever (CSF), caused by CSF virus (CSFV), which is a highly infectious endemic disease of domestic pigs in India. The post-mortem findings and serum CSFV-specific antibody titres, along with the isolation of CSFV from two pygmy hogs, and further confirmation by CSFV genomic E2 and 5' untranslated region (UTR) gene amplification in PCR (polymerase chain reaction), clearly established the cause of death of the pygmy hogs. Further, on phylogenetic analysis, the pygmy hog CSFV 5' UTR sequences were grouped in the genotype 1.1 cluster of Indian CSFVs, and hence the strains causing infection were closely related to CSFV isolates circulating in domestic pigs. Therefore, the occurrence of CSF in this endangered species may pose a potent threat to their existence unless properly controlled, and thus it needs urgent attention. To the authors' knowledge this is the first report on CSF in pygmy hogs.

  13. Classical Trajectory and Monte Carlo Techniques

    NASA Astrophysics Data System (ADS)

    Olson, Ronald

    The classical trajectory Monte Carlo (CTMC) method originated with Hirschfelder, who studied the H + D2 exchange reaction using a mechanical calculator [58.1]. With the availability of computers, the CTMC method was actively applied to a large number of chemical systems to determine reaction rates, and final state vibrational and rotational populations (see, e.g., Karplus et al. [58.2]). For atomic physics problems, a major step was introduced by Abrines and Percival [58.3] who employed Kepler's equations and the Bohr-Sommerfield model for atomic hydrogen to investigate electron capture and ionization for intermediate velocity collisions of H+ + H. An excellent description is given by Percival and Richards [58.4]. The CTMC method has a wide range of applicability to strongly-coupled systems, such as collisions by multiply-charged ions [58.5]. In such systems, perturbation methods fail, and basis set limitations of coupled-channel molecular- and atomic-orbital techniques have difficulty in representing the multitude of activeexcitation, electron capture, and ionization channels. Vector- and parallel-processors now allow increasingly detailed study of the dynamics of the heavy projectile and target, along with the active electrons.

  14. Desmosomes: new perspectives on a classic.

    PubMed

    Green, Kathleen J; Simpson, Cory L

    2007-11-01

    Desmosomes are highly specialized anchoring junctions that link intermediate filaments to sites of intercellular adhesion, thus facilitating the formation of a supracellular scaffolding that distributes mechanical forces throughout a tissue. These junctions are thus particularly important for maintaining the integrity of tissues that endure physical stress, such as the epidermis and myocardium. The importance of the classic mechanical functions of desmosomal constituents is underscored by pathologies reported in animal models and an ever-expanding list of human mutations that target both desmosomal cadherins and their associated cytoskeletal anchoring proteins. However, the notion that desmosomes are static structures that exist simply to glue cells together belies their susceptibility to remodeling in response to environmental cues and their important tissue-specific roles in cell behavior and signaling. Here, we review the molecular blueprint of the desmosome and models for assembling its protein components to form an adhesive interface and the desmosomal plaque. We also discuss emerging evidence of supra-adhesive roles for desmosomal proteins in regulating tissue morphogenesis and homeostasis. Finally, we highlight the dynamic nature of these adhesive organelles, examining mechanisms in health and disease for modulating adhesive strength and stability of desmosomes.

  15. Tachyons in classical de Sitter vacua

    NASA Astrophysics Data System (ADS)

    Junghans, Daniel

    2016-06-01

    We revisit the possibility of de Sitter vacua and slow-roll inflation in type II string theory at the level of the classical two-derivative supergravity approximation. Previous attempts at explicit constructions were plagued by ubiquitous tachyons with a large η parameter whose origin has not been fully understood so far. In this paper, we determine and explain the tachyons in two setups that are known to admit unstable dS critical points: an SU(3) structure compactification of massive type IIA with O6-planes and an SU(2) structure compactification of type IIB with O5/O7-planes. We explicitly show that the tachyons are always close to, but never fully aligned with the sgoldstino direction in the considered examples and argue that this behavior is explained by a generalized version of a no-go theorem by Covi et al, which holds in the presence of large mixing in the mass matrix between the sgoldstino and the orthogonal moduli. This observation may also provide a useful stability criterion for general dS vacua in supergravity and string theory.

  16. The classic cadherins in synaptic specificity

    PubMed Central

    Basu, Raunak; Taylor, Matthew R; Williams, Megan E

    2015-01-01

    During brain development, billions of neurons organize into highly specific circuits. To form specific circuits, neurons must build the appropriate types of synapses with appropriate types of synaptic partners while avoiding incorrect partners in a dense cellular environment. Defining the cellular and molecular rules that govern specific circuit formation has significant scientific and clinical relevance because fine scale connectivity defects are thought to underlie many cognitive and psychiatric disorders. Organizing specific neural circuits is an enormously complicated developmental process that requires the concerted action of many molecules, neural activity, and temporal events. This review focuses on one class of molecules postulated to play an important role in target selection and specific synapse formation: the classic cadherins. Cadherins have a well-established role in epithelial cell adhesion, and although it has long been appreciated that most cadherins are expressed in the brain, their role in synaptic specificity is just beginning to be unraveled. Here, we review past and present studies implicating cadherins as active participants in the formation, function, and dysfunction of specific neural circuits and pose some of the major remaining questions. PMID:25837840

  17. Classical interaction model for the water molecule.

    PubMed

    Baranyai, András; Bartók, Albert

    2007-05-14

    The authors propose a new classical model for the water molecule. The geometry of the molecule is built on the rigid TIP5P model and has the experimental gas phase dipole moment of water created by four equal point charges. The model preserves its rigidity but the size of the charges increases or decreases following the electric field created by the rest of the molecules. The polarization is expressed by an electric field dependent nonlinear polarization function. The increasing dipole of the molecule slightly increases the size of the water molecule expressed by the oxygen-centered sigma parameter of the Lennard-Jones interaction. After refining the adjustable parameters, the authors performed Monte Carlo simulations to check the ability of the new model in the ice, liquid, and gas phases. They determined the density and internal energy of several ice polymorphs, liquid water, and gaseous water and calculated the heat capacity, the isothermal compressibility, the isobar heat expansion coefficients, and the dielectric constant of ambient water. They also determined the pair-correlation functions of ambient water and calculated the energy of the water dimer. The accuracy of theirs results was satisfactory.

  18. Classical and quantum stability in putative landscapes

    NASA Astrophysics Data System (ADS)

    Dine, Michael

    2017-01-01

    Landscape analyses often assume the existence of large numbers of fields, N , with all of the many couplings among these fields (subject to constraints such as local supersymmetry) selected independently and randomly from simple (say Gaussian) distributions. We point out that unitarity and perturbativity place significant constraints on behavior of couplings with N , eliminating otherwise puzzling results. In would-be flux compactifications of string theory, we point out that in order that there be large numbers of light fields, the compactification radii must scale as a positive power of N ; scaling of couplings with N may also be necessary for perturbativity. We show that in some simple string theory settings with large numbers of fields, for fixed R and string coupling, one can bound certain sums of squares of couplings by order one numbers. This may argue for strong correlations, possibly calling into question the assumption of uncorrelated distributions. We consider implications of these considerations for classical and quantum stability of states without supersymmetry, with low energy supersymmetry arising from tuning of parameters, and with dynamical breaking of supersymmetry.

  19. Augmented classical least squares multivariate spectral analysis

    DOEpatents

    Haaland, David M.; Melgaard, David K.

    2004-02-03

    A method of multivariate spectral analysis, termed augmented classical least squares (ACLS), provides an improved CLS calibration model when unmodeled sources of spectral variation are contained in a calibration sample set. The ACLS methods use information derived from component or spectral residuals during the CLS calibration to provide an improved calibration-augmented CLS model. The ACLS methods are based on CLS so that they retain the qualitative benefits of CLS, yet they have the flexibility of PLS and other hybrid techniques in that they can define a prediction model even with unmodeled sources of spectral variation that are not explicitly included in the calibration model. The unmodeled sources of spectral variation may be unknown constituents, constituents with unknown concentrations, nonlinear responses, non-uniform and correlated errors, or other sources of spectral variation that are present in the calibration sample spectra. Also, since the various ACLS methods are based on CLS, they can incorporate the new prediction-augmented CLS (PACLS) method of updating the prediction model for new sources of spectral variation contained in the prediction sample set without having to return to the calibration process. The ACLS methods can also be applied to alternating least squares models. The ACLS methods can be applied to all types of multivariate data.

  20. Augmented Classical Least Squares Multivariate Spectral Analysis

    DOEpatents

    Haaland, David M.; Melgaard, David K.

    2005-07-26

    A method of multivariate spectral analysis, termed augmented classical least squares (ACLS), provides an improved CLS calibration model when unmodeled sources of spectral variation are contained in a calibration sample set. The ACLS methods use information derived from component or spectral residuals during the CLS calibration to provide an improved calibration-augmented CLS model. The ACLS methods are based on CLS so that they retain the qualitative benefits of CLS, yet they have the flexibility of PLS and other hybrid techniques in that they can define a prediction model even with unmodeled sources of spectral variation that are not explicitly included in the calibration model. The unmodeled sources of spectral variation may be unknown constituents, constituents with unknown concentrations, nonlinear responses, non-uniform and correlated errors, or other sources of spectral variation that are present in the calibration sample spectra. Also, since the various ACLS methods are based on CLS, they can incorporate the new prediction-augmented CLS (PACLS) method of updating the prediction model for new sources of spectral variation contained in the prediction sample set without having to return to the calibration process. The ACLS methods can also be applied to alternating least squares models. The ACLS methods can be applied to all types of multivariate data.

  1. Augmented Classical Least Squares Multivariate Spectral Analysis

    DOEpatents

    Haaland, David M.; Melgaard, David K.

    2005-01-11

    A method of multivariate spectral analysis, termed augmented classical least squares (ACLS), provides an improved CLS calibration model when unmodeled sources of spectral variation are contained in a calibration sample set. The ACLS methods use information derived from component or spectral residuals during the CLS calibration to provide an improved calibration-augmented CLS model. The ACLS methods are based on CLS so that they retain the qualitative benefits of CLS, yet they have the flexibility of PLS and other hybrid techniques in that they can define a prediction model even with unmodeled sources of spectral variation that are not explicitly included in the calibration model. The unmodeled sources of spectral variation may be unknown constituents, constituents with unknown concentrations, nonlinear responses, non-uniform and correlated errors, or other sources of spectral variation that are present in the calibration sample spectra. Also, since the various ACLS methods are based on CLS, they can incorporate the new prediction-augmented CLS (PACLS) method of updating the prediction model for new sources of spectral variation contained in the prediction sample set without having to return to the calibration process. The ACLS methods can also be applied to alternating least squares models. The ACLS methods can be applied to all types of multivariate data.

  2. High vacuum cells for classical surface techniques

    SciTech Connect

    Martinez, Imee Su; Baldelli, Steven

    2010-04-15

    Novel glass cells were designed and built to be able to perform surface potential and surface tension measurements in a contained environment. The cells can withstand pressures of approximately 1x10{sup -6} Torr, providing a reasonable level of control in terms of the amounts of volatile contaminants during experimentation. The measurements can take several hours; thus the cells help maintain the integrity of the sample in the course of the experiment. To test for the feasibility of the cell design, calibration measurements were performed. For the surface potential cell, the modified TREK 6000B-7C probe exhibited performance comparable to its unmodified counterpart. The correlation measurements between applied potential on the test surface and the measured potential showed R-values very close to 1 as well as standard deviation values of less than 1. Results also demonstrate improved measurement values for experiments performed in vacuum. The surface tension cell, on the other hand, which was used to perform the pendant drop method, was tested on common liquids and showed percentage errors of 0.5% when compared to literature values. The fabricated cells redefine measurements using classical surface techniques, providing unique and novel methods of sample preparation, premeasurement preparation, and sample analysis at highly beneficial expenditure cost.

  3. Classical intracranial chondrosarcoma: A case report

    PubMed Central

    Chi, Jingyang; Zhang, Mingchao; Kang, Jianmin

    2016-01-01

    Intracranial chondrosarcoma is a rare malignant cartilage-forming tumor, with only a small number of cases in the posterior cranial fossa reported previously. The present study reports the case of a 40-year-old male patient who was admitted to Tianjin Huanhu Hospital with a progressive headache and dizziness that had lasted for 2 years. Physical and neurological examinations were normal. Radiography of the skull identified an opaque lesion in the left frontal region of the brain. Cranial computed tomography and magnetic resonance imaging revealed a lesion with calcification and homogenous contrast enhancement in the left frontal region. Subsequently, the patient underwent bicoronal craniotomy and gross total resection of the tumor. Pathological examination confirmed the diagnosis of classical intracranial chondrosarcoma. The patient was discharged 10 days after surgery, with no neurological deficit. One month after initial discharge, the patient underwent γ-knife treatment. A follow-up examination 9 months after surgery revealed that the patient was still alive and had returned to work, with no obvious symptoms or evidence of recurrence. PMID:27895770

  4. New developments in classical chaotic scattering.

    PubMed

    Seoane, Jesús M; Sanjuán, Miguel A F

    2013-01-01

    Classical chaotic scattering is a topic of fundamental interest in nonlinear physics due to the numerous existing applications in fields such as celestial mechanics, atomic and nuclear physics and fluid mechanics, among others. Many new advances in chaotic scattering have been achieved in the last few decades. This work provides a current overview of the field, where our attention has been mainly focused on the most important contributions related to the theoretical framework of chaotic scattering, the fractal dimension, the basins boundaries and new applications, among others. Numerical techniques and algorithms, as well as analytical tools used for its analysis, are also included. We also show some of the experimental setups that have been implemented to study diverse manifestations of chaotic scattering. Furthermore, new theoretical aspects such as the study of this phenomenon in time-dependent systems, different transitions and bifurcations to chaotic scattering and a classification of boundaries in different types according to symbolic dynamics are also shown. Finally, some recent progress on chaotic scattering in higher dimensions is also described.

  5. Clean Quantum and Classical Communication Protocols

    NASA Astrophysics Data System (ADS)

    Buhrman, Harry; Christandl, Matthias; Perry, Christopher; Zuiddam, Jeroen

    2016-12-01

    By how much must the communication complexity of a function increase if we demand that the parties not only correctly compute the function but also return all registers (other than the one containing the answer) to their initial states at the end of the communication protocol? Protocols that achieve this are referred to as clean and the associated cost as the clean communication complexity. Here we present clean protocols for calculating the inner product of two n -bit strings, showing that (in the absence of preshared entanglement) at most n +3 qubits or n +O (√{n }) bits of communication are required. The quantum protocol provides inspiration for obtaining the optimal method to implement distributed cnot gates in parallel while minimizing the amount of quantum communication. For more general functions, we show that nearly all Boolean functions require close to 2 n bits of classical communication to compute and close to n qubits if the parties have access to preshared entanglement. Both of these values are maximal for their respective paradigms.

  6. Classical Acoustic Echoes in Model Glasses

    NASA Astrophysics Data System (ADS)

    Burton, Justin; Nagel, Sidney

    2013-03-01

    For the last 40 years, the low-temperature excitations in glasses have traditionally been explained in terms of a distribution of dilute, two-level quantum states that are created by clusters of particles tunneling between two nearly degenerate ground states. Strong evidence for this model has come from ultrasonic saturation effects and acoustic echoes observed in experiments. Recently, a classical analysis of vibrational modes in model glasses has shown that at low frequencies, the modes are quasi-localized and highly anharmonic. Using molecular dynamics simulations, we show that this anharmonicity can produce an acoustic echo due to the shift in the mode frequency with increasing amplitude. We observe this both in jammed packings of spherical particles with finite-range, Hertzian repulsions, and in model glasses interacting with a Lennard-Jones potential. In contrast to pulse echoes in two-level systems, a distinguishing feature of these ``anharmonic echoes'' is the appearance of multiple echoes after two excitation pulses, a feature also observed in experiments.

  7. The Directedness of Time in Classical Cosmology

    NASA Astrophysics Data System (ADS)

    Bartels, Andreas; Wohlfarth, Daniel

    2014-03-01

    The aim of this paper is to show that a new understanding of fundamentality can be applied successfully in classical cosmology based on General Relativity. We are thereby able to achieve an account of cosmological time asymmetry as an intrinsic and fun-damental property of the universe. First, we consider Price's arguments against the fundamental status of time-asymmetry (Price (1996, 2002, 2011)). We show that these arguments have some force, but their force depends on understanding fundamentality as law-likeness. Second, we show that alternative approaches attempting to explain time directedness either by applying an anthropic strategy based on a multiverse approach, or by using the empirical fact of accelerated expansion of the universe, equally fail to provide a fundamental explanation of time directedness. In the third part, we present our own new concept of fundamentality based on properties of the solution space of fundamental laws. We demonstrate how this new concept of fundamentality is effective in understanding the cosmological asymmetry.

  8. Classical limit of diagonal form factors and HHL correlators

    NASA Astrophysics Data System (ADS)

    Bajnok, Zoltan; Janik, Romuald A.

    2017-01-01

    We propose an expression for the classical limit of diagonal form factors in which we integrate the corresponding observable over the moduli space of classical solutions. In infinite volume the integral has to be regularized by proper subtractions and we present the one, which corresponds to the classical limit of the connected diagonal form factors. In finite volume the integral is finite and can be expressed in terms of the classical infinite volume diagonal form factors and subvolumes of the moduli space. We analyze carefully the periodicity properties of the finite volume moduli space and found a classical analogue of the Bethe-Yang equations. By applying the results to the heavy-heavy-light three point functions we can express their strong coupling limit in terms of the classical limit of the sine-Gordon diagonal form factors.

  9. Nondivergent classical response functions from uncertainty principle: quasiperiodic systems.

    PubMed

    Kryvohuz, Maksym; Cao, Jianshu

    2005-01-08

    Time-divergence in linear and nonlinear classical response functions can be removed by taking a phase-space average within the quantized uncertainty volume O(hn) around the microcanonical energy surface. For a quasiperiodic system, the replacement of the microcanonical distribution density in the classical response function with the quantized uniform distribution density results in agreement of quantum and classical expressions through Heisenberg's correspondence principle: each matrix element (u/alpha(t)/v) corresponds to the (u-v)th Fourier component of alpha(t) evaluated along the classical trajectory with mean action (Ju+Jv)/2. Numerical calculations for one- and two-dimensional systems show good agreement between quantum and classical results. The generalization to the case of N degrees of freedom is made. Thus, phase-space averaging within the quantized uncertainty volume provides a useful way to establish the classical-quantum correspondence for the linear and nonlinear response functions of a quasiperiodic system.

  10. Functional methods underlying classical mechanics, relativity and quantum theory

    NASA Astrophysics Data System (ADS)

    Kryukov, A.

    2013-04-01

    The paper investigates the physical content of a recently proposed mathematical framework that unifies the standard formalisms of classical mechanics, relativity and quantum theory. In the framework states of a classical particle are identified with Dirac delta functions. The classical space is "made" of these functions and becomes a submanifold in a Hilbert space of states of the particle. The resulting embedding of the classical space into the space of states is highly non-trivial and accounts for numerous deep relations between classical and quantum physics and relativity. One of the most striking results is the proof that the normal probability distribution of position of a macroscopic particle (equivalently, position of the corresponding delta state within the classical space submanifold) yields the Born rule for transitions between arbitrary quantum states.

  11. Classical-driving-assisted quantum speed-up

    NASA Astrophysics Data System (ADS)

    Zhang, Ying-Jie; Han, Wei; Xia, Yun-Jie; Cao, Jun-Peng; Fan, Heng

    2015-03-01

    We propose a method of accelerating the speed of evolution of an open system by an external classical driving field for a qubit in a zero-temperature structured reservoir. It is shown that, with a judicious choice of the driving strength of the applied classical field, a speed-up evolution of an open system can be achieved in both the weak system-environment couplings and the strong system-environment couplings. By considering the relationship between non-Makovianity of environment and the classical field, we can drive the open system from the Markovian to the non-Markovian regime by manipulating the driving strength of the classical field. That is the intrinsic physical reason that the classical field may induce the speed-up process. In addition, the role of this classical field on the variation of quantum evolution speed in the whole decoherence process is discussed.

  12. Classical simulation of quantum energy flow in biomolecules.

    PubMed

    Stock, Gerhard

    2009-03-20

    Based on a comparison of classical and quantum-mechanical perturbation theory, the validity of classical nonequilibrium molecular dynamics simulations to describe vibrational energy redistribution in biomolecules is studied. Adopting a small model peptide in aqueous solution as an example, the theory correctly predicts quantum correction factors that need to be applied to the results of classical simulations in order to match the correct quantum results.

  13. On the correspondence between quantum and classical variational principles

    DOE PAGES

    Ruiz, D. E.; Dodin, I. Y.

    2015-06-10

    Here, classical variational principles can be deduced from quantum variational principles via formal reparameterization of the latter. It is shown that such reparameterization is possible without invoking any assumptions other than classicality and without appealing to dynamical equations. As examples, first principle variational formulations of classical point-particle and cold-fluid motion are derived from their quantum counterparts for Schrodinger, Pauli, and Klein-Gordon particles.

  14. Polaractivation for classical zero-error capacity of qudit channels

    SciTech Connect

    Gyongyosi, Laszlo; Imre, Sandor

    2014-12-04

    We introduce a new phenomenon for zero-error transmission of classical information over quantum channels that initially were not able for zero-error classical communication. The effect is called polaractivation, and the result is similar to the superactivation effect. We use the Choi-Jamiolkowski isomorphism and the Schmidt-theorem to prove the polaractivation of classical zero-error capacity and define the polaractivator channel coding scheme.

  15. Classical phase space and statistical mechanics of identical particles.

    PubMed

    Hansson, T H; Isakov, S B; Leinaas, J M; Lindström, U

    2001-02-01

    Starting from the quantum theory of identical particles, we show how to define a classical mechanics that retains information about the quantum statistics. We consider two examples of relevance for the quantum Hall effect: identical particles in the lowest Landau level, and vortices in the Chern-Simons Ginzburg-Landau model. In both cases the resulting classical statistical mechanics is shown to be a nontrivial classical limit of Haldane's exclusion statistics.

  16. [Classic and aggressive Kaposi sarcoma with bone involvement].

    PubMed

    Sbiyaa, Mouhcine; El Alaoui, Adil; El Bardai, Mohammed; Mezzani, Amine; Lahrach, Kamal; Marzouki, Amine; Boutayeb, Fawzi

    2016-01-01

    Classic Kaposi sarcoma is a multifocal rare tumor originating from vascular endothelial cells with progressive evolution and little malignant predisposition. Although Kaposi sarcoma with extensive visceral involvement is sometimes observed among HIV-positive patients, tumor dissemination to visceral lymph nodes in classic SK remains very rare. We report a rare case of aggressive classic Kaposi sarcoma of the hand with a rapid and destructive development.

  17. Nonclassicality in phase by breaking classical bounds on statistics

    SciTech Connect

    Martin, Daniel; Luis, Alfredo

    2010-09-15

    We derive upper bounds on the statistics of phase and phase difference that are satisfied by all classical states. They are obtained by finding the maximum projection of classical states on phase states. For a single-mode phase, meaningful bounds are obtained conditioned to a fixed mean number of photons. We also derive classical bounds for the projection on phase-coherent states, discussing their relation with phase-state bounds within the context of analytic representations. We find states with nonclassical phase properties disclosed by the violation of these classical bounds. These are quadrature and SU(2) squeezed states and phase-coherent states.

  18. Non-Classical Congenital Adrenal Hyperplasia in Childhood

    PubMed Central

    Kurtoğlu, Selim; Hatipoğlu, Nihal

    2017-01-01

    Congenital adrenal hyperplasia (CAH) is classified as classical CAH and non-classical CAH (NCCAH). In the classical type, the most severe form comprises both salt-wasting and simple virilizing forms. In the non-classical form, diagnosis can be more confusing because the patient may remain asymptomatic or the condition may be associated with signs of androgen excess in the postnatal period or in the later stages of life. This review paper will include information on clinical findings, symptoms, diagnostic approaches, and treatment modules of NCCAH. PMID:27354284

  19. Computational quantum-classical boundary of noisy commuting quantum circuits

    NASA Astrophysics Data System (ADS)

    Fujii, Keisuke; Tamate, Shuhei

    2016-05-01

    It is often said that the transition from quantum to classical worlds is caused by decoherence originated from an interaction between a system of interest and its surrounding environment. Here we establish a computational quantum-classical boundary from the viewpoint of classical simulatability of a quantum system under decoherence. Specifically, we consider commuting quantum circuits being subject to decoherence. Or equivalently, we can regard them as measurement-based quantum computation on decohered weighted graph states. To show intractability of classical simulation in the quantum side, we utilize the postselection argument and crucially strengthen it by taking noise effect into account. Classical simulatability in the classical side is also shown constructively by using both separable criteria in a projected-entangled-pair-state picture and the Gottesman-Knill theorem for mixed state Clifford circuits. We found that when each qubit is subject to a single-qubit complete-positive-trace-preserving noise, the computational quantum-classical boundary is sharply given by the noise rate required for the distillability of a magic state. The obtained quantum-classical boundary of noisy quantum dynamics reveals a complexity landscape of controlled quantum systems. This paves a way to an experimentally feasible verification of quantum mechanics in a high complexity limit beyond classically simulatable region.

  20. Computational quantum-classical boundary of noisy commuting quantum circuits

    PubMed Central

    Fujii, Keisuke; Tamate, Shuhei

    2016-01-01

    It is often said that the transition from quantum to classical worlds is caused by decoherence originated from an interaction between a system of interest and its surrounding environment. Here we establish a computational quantum-classical boundary from the viewpoint of classical simulatability of a quantum system under decoherence. Specifically, we consider commuting quantum circuits being subject to decoherence. Or equivalently, we can regard them as measurement-based quantum computation on decohered weighted graph states. To show intractability of classical simulation in the quantum side, we utilize the postselection argument and crucially strengthen it by taking noise effect into account. Classical simulatability in the classical side is also shown constructively by using both separable criteria in a projected-entangled-pair-state picture and the Gottesman-Knill theorem for mixed state Clifford circuits. We found that when each qubit is subject to a single-qubit complete-positive-trace-preserving noise, the computational quantum-classical boundary is sharply given by the noise rate required for the distillability of a magic state. The obtained quantum-classical boundary of noisy quantum dynamics reveals a complexity landscape of controlled quantum systems. This paves a way to an experimentally feasible verification of quantum mechanics in a high complexity limit beyond classically simulatable region. PMID:27189039

  1. Beyond quantum-classical analogies: high time for agreement?

    NASA Astrophysics Data System (ADS)

    Marrocco, Michele

    Lately, many quantum-classical analogies have been investigated and published in many acknowledged journals. Such a surge of research on conceptual connections between quantum and classical physics forces us to ask whether the correspondence between the quantum and classical interpretation of the reality is deeper than the correspondence principle stated by Bohr. Here, after a short introduction to quantum-classical analogies from the recent literature, we try to examine the question from the perspective of a possible agreement between quantum and classical laws. A paradigmatic example is given in the striking equivalence between the classical Mie theory of electromagnetic scattering from spherical scatterers and the corresponding quantum-mechanical wave scattering analyzed in terms of partial waves. The key features that make the correspondence possible are examined and finally employed to deal with the fundamental blackbody problem that marks the initial separation between classical and quantum physics. The procedure allows us to recover the blackbody spectrum in classical terms and the proof is rich in consequences. Among them, the strong analogy between the quantum vacuum and its classical counterpart.

  2. Computational quantum-classical boundary of noisy commuting quantum circuits.

    PubMed

    Fujii, Keisuke; Tamate, Shuhei

    2016-05-18

    It is often said that the transition from quantum to classical worlds is caused by decoherence originated from an interaction between a system of interest and its surrounding environment. Here we establish a computational quantum-classical boundary from the viewpoint of classical simulatability of a quantum system under decoherence. Specifically, we consider commuting quantum circuits being subject to decoherence. Or equivalently, we can regard them as measurement-based quantum computation on decohered weighted graph states. To show intractability of classical simulation in the quantum side, we utilize the postselection argument and crucially strengthen it by taking noise effect into account. Classical simulatability in the classical side is also shown constructively by using both separable criteria in a projected-entangled-pair-state picture and the Gottesman-Knill theorem for mixed state Clifford circuits. We found that when each qubit is subject to a single-qubit complete-positive-trace-preserving noise, the computational quantum-classical boundary is sharply given by the noise rate required for the distillability of a magic state. The obtained quantum-classical boundary of noisy quantum dynamics reveals a complexity landscape of controlled quantum systems. This paves a way to an experimentally feasible verification of quantum mechanics in a high complexity limit beyond classically simulatable region.

  3. Sharing the Quantum State and the Classical Information Simultaneously

    NASA Astrophysics Data System (ADS)

    Qin, Huawang; Dai, Yuewei

    2016-08-01

    An efficient quantum secret sharing scheme is proposed, in which the quantum state and the classical information can be shared simultaneously through only one distribution. The dealer uses the operations of quantum-controlled-not and Hadamard gate to encode the secret quantum state and classical information, and the participants use the single-particle measurements to recover the original quantum state and classical information. Compared to the existing schemes, our scheme is more efficient when the quantum state and the classical information need to be shared simultaneously.

  4. Classical novae and recurrent novae: General properties

    NASA Technical Reports Server (NTRS)

    Hack, Margherita; Selvelli, Pierluigi; Duerbeck, Hilmar W.

    1993-01-01

    We describe the observable characteristics of classical novae and recurrent novae obtained by different techniques (photometry, spectroscopy, and imaging) in all the available spectral ranges. We consider the three stages in the life of a nova: quiescence (pre- and post-outburst), outburst, final decline and nebular phase. We describe the photometric properties during the quiescent phase. We describe the photometric properties during outburst, the classification according the rate of decline (magnitudes per day), which permits us to define very fast, fast, intermediate, slow, and very slow novae and the correlation between luminosity and speed class. We report the scanty data on the spectra of the few known prenovae and those on the spectra of old novae and those of dwarf novae and nova-like, which, however, are almost undistinguishable. We describe the typical spectra appearing from the beginning of the outburst, just before maximum, up to the nebular phase and the correlation between spectral type at maximum, expansional velocity, and speed class of the nova. We report the existing infrared observations, which permit us to explain some of the characteristics of the outburst light curve, and give evidence of the formation of a dust shell in slow and intermediate novae (with the important exception of the very slow nova HR Del 1967) and its absence or quasi-absence in fast novae. The ultraviolet and X-ray observations are described. The X ray observations of novae, mainly from the two satellites EINSTEIN and EXOSAT, are reported. Observations of the final decline and of the envelopes appearing several months after outburst are also reported.

  5. Classic versus millennial medical lab anatomy.

    PubMed

    Benninger, Brion; Matsler, Nik; Delamarter, Taylor

    2014-10-01

    This study investigated the integration, implementation, and use of cadaver dissection, hospital radiology modalities, surgical tools, and AV technology during a 12-week contemporary anatomy course suggesting a millennial laboratory. The teaching of anatomy has undergone the greatest fluctuation of any of the basic sciences during the past 100 years in order to make room for the meteoric rise in molecular sciences. Classically, anatomy consisted of a 2-year methodical, horizontal, anatomy course; anatomy has now morphed into a 12-week accelerated course in a vertical curriculum, at most institutions. Surface and radiological anatomy is the language for all clinicians regardless of specialty. The objective of this study was to investigate whether integration of full-body dissection anatomy and modern hospital technology, during the anatomy laboratory, could be accomplished in a 12-week anatomy course. Literature search was conducted on anatomy text, journals, and websites regarding contemporary hospital technology integrating multiple image mediums of 37 embalmed cadavers, surgical suite tools and technology, and audio/visual technology. Surgical and radiology professionals were contracted to teach during the anatomy laboratory. Literature search revealed no contemporary studies integrating full-body dissection with hospital technology and behavior. About 37 cadavers were successfully imaged with roentograms, CT, and MRI scans. Students were in favor of the dynamic laboratory consisting of multiple activity sessions occurring simultaneously. Objectively, examination scores proved to be a positive outcome and, subjectively, feedback from students was overwhelmingly positive. Despite the surging molecular based sciences consuming much of the curricula, full-body dissection anatomy is irreplaceable regarding both surface and architectural, radiological anatomy. Radiology should not be a small adjunct to understand full-body dissection, but rather, full-body dissection

  6. Quantum physics of classical waves in plasma

    NASA Astrophysics Data System (ADS)

    Dodin, I. Y.

    2012-10-01

    The Lagrangian approach to plasma wave physics is extended to a universal nonlinear theory which yields generic equations invariant with respect to the wave nature. The traditional understanding of waves as solutions of the Maxwell-Vlasov system is abandoned. Oscillations are rather treated as physical entities, namely, abstract vectors |ψ> in a specific Hilbert space. The invariant product <ψ|ψ> is the total action and has the sign of the oscillation energy. The action density is then an operator. Projections of the corresponding operator equation generate assorted wave kinetic equations; the nonlinear Wigner-Moyal equation is just one example and, in fact, may be more delicate than commonly assumed. The linear adiabatic limit of this classical theory leads to quantum mechanics in its general form. The action conservation theorem, together with its avatars such as Manley-Rowe relations, then becomes manifest and in partial equilibrium can modify statistical properties of plasma fluctuations. In the quasi-monochromatic limit geometrical optics (GO) is recovered and can as well be understood as a particular field theory in its own right. For linear waves, the energy-momentum equations, in both canonical and (often) kinetic form, then follow automatically, even without a reference to electromagnetism. Yet for waves in plasma the general GO Lagrangian is also derived explicitly, in terms of single-particle oscillation-center Hamiltonians. Applications to various plasma waves are then discussed with an emphasis on the advantages of an abstract theory. Specifically covered are nonlinear dispersion, dynamics, and stability of BGK modes, and also other wave transformations in laboratory and cosmological plasmas.

  7. Classically conditioned postural reflex in cerebellar patients.

    PubMed

    Kolb, F P; Lachauer, S; Maschke, M; Timmann, D

    2004-09-01

    The aim of the current study was to compare postural responses to repetitive platform-evoked perturbations in cerebellar patients with those of healthy subjects using a classical conditioning paradigm. The perturbations consisted of tilting of the platform (unconditioned stimulus: US) at random time intervals, preceded by an auditory signal that represented the conditioning stimulus (CS). Physiological reactions were recorded biomechanically by measuring the vertical ground forces, yielding the center of vertical pressure (CVP), and electrophysiologically by EMG measurements of the main muscle groups of both legs. The recording session consisted of a control section with US-alone trials, a testing section with paired stimuli and a brief final section with US-alone trials. Healthy control subjects were divided into those establishing conditioned responses (CR) in all muscles tested (strategy I) and those with CR in the gastrocnemius muscles only (strategy II), suggesting an associative motor-related process is involved. Patients with a diffuse, non-localized disease were almost unable to establish CR. This was also true for a patient with a focal surgical lesion with no CR on the affected side but who, simultaneously, showed an essentially normal CR incidence on the intact side. During US-alone trials healthy controls exhibited a remarkable decay of the UR amplitude due to a non-associative motor-related process such as habituation. The decay was most prominent in the paired trials section. In contrast, patients showed no significant differences in the UR amplitude throughout the entire recording session. Analysis of the CVP supported the electrophysiological findings, showing CR in the controls only. The differences between the responses of control subjects and those of the cerebellar patients imply strongly that the cerebellum is involved critically in controlling associative and non-associative motor-related processes.

  8. Polymerization by classical and frustrated Lewis pairs.

    PubMed

    Chen, Eugene Y-X

    2013-01-01

    Main-group classical and frustrated Lewis pairs (CLPs and FLPs) comprising strong Lewis acids (LAs) and strong Lewis bases (LBs) are highly active for polymerization of conjugated polar alkenes, affording typically high molecular weight polymers with relatively narrow molecular weight distributions. Especially effective systems are the Lewis pairs (LPs) consisting of the strong LA Al(C6F5)3 and strong LBs, such as achiral phosphines and chiral chelating diphosphines, N-heterocyclic carbenes, and phosphazene superbases, for polymerization of methacrylates and acrylamides as well as renewable α-methylene-γ-butyrolactones. Chain initiation involves cooperative addition of LPs to the monomer to generate zwitterionic active species, and chain propagation proceeds via a bimetallic, activated-monomer addition mechanism. Transition metal nucleophile/electrophile pairs comprising neutral metallocene bis(ester enolate)s and strong LAs E(C6F5)3 (E = Al, B) generate two drastically different polymerization systems, depending on the LA. With E = Al, catalyst activation and chain initiating events lead to dually active ion-pairs, thereby effecting ion-pairing polymerization that affords polymers with unique stereo-multiblock microstructures. With E = B, on the other hand, the FLP-induced catalyst activation generates metallacyclic cations paired with the hydridoborate anion [HB(C6F5)3](-); uniquely, such ion-pairs effect catalytic polymerization of conjugated polar alkenes by an H-shuttling mechanism, with the cation catalyzing chain growth and the anion promoting chain transfer by shuttling the hydride between the cation and anion centers through the neutral borane.

  9. Quantum and classical behavior in interacting bosonic systems

    NASA Astrophysics Data System (ADS)

    Hertzberg, Mark P.

    2016-11-01

    It is understood that in free bosonic theories, the classical field theory accurately describes the full quantum theory when the occupancy numbers of systems are very large. However, the situation is less understood in interacting theories, especially on time scales longer than the dynamical relaxation time. Recently there have been claims that the quantum theory deviates spectacularly from the classical theory on this time scale, even if the occupancy numbers are extremely large. Furthermore, it is claimed that the quantum theory quickly thermalizes while the classical theory does not. The evidence for these claims comes from noticing a spectacular difference in the time evolution of expectation values of quantum operators compared to the classical micro-state evolution. If true, this would have dramatic consequences for many important phenomena, including laboratory studies of interacting BECs, dark matter axions, preheating after inflation, etc. In this work we critically examine these claims. We show that in fact the classical theory can describe the quantum behavior in the high occupancy regime, even when interactions are large. The connection is that the expectation values of quantum operators in a single quantum micro-state are approximated by a corresponding classical ensemble average over many classical micro-states. Furthermore, by the ergodic theorem, a classical ensemble average of local fields with statistical translation invariance is the spatial average of a single micro-state. So the correlation functions of the quantum and classical field theories of a single micro-state approximately agree at high occupancy, even in interacting systems. Furthermore, both quantum and classical field theories can thermalize, when appropriate coarse graining is introduced, with the classical case requiring a cutoff on low occupancy UV modes. We discuss applications of our results.

  10. Quantum and classical behavior in interacting bosonic systems

    SciTech Connect

    Hertzberg, Mark P.

    2016-11-21

    It is understood that in free bosonic theories, the classical field theory accurately describes the full quantum theory when the occupancy numbers of systems are very large. However, the situation is less understood in interacting theories, especially on time scales longer than the dynamical relaxation time. Recently there have been claims that the quantum theory deviates spectacularly from the classical theory on this time scale, even if the occupancy numbers are extremely large. Furthermore, it is claimed that the quantum theory quickly thermalizes while the classical theory does not. The evidence for these claims comes from noticing a spectacular difference in the time evolution of expectation values of quantum operators compared to the classical micro-state evolution. If true, this would have dramatic consequences for many important phenomena, including laboratory studies of interacting BECs, dark matter axions, preheating after inflation, etc. In this work we critically examine these claims. We show that in fact the classical theory can describe the quantum behavior in the high occupancy regime, even when interactions are large. The connection is that the expectation values of quantum operators in a single quantum micro-state are approximated by a corresponding classical ensemble average over many classical micro-states. Furthermore, by the ergodic theorem, a classical ensemble average of local fields with statistical translation invariance is the spatial average of a single micro-state. So the correlation functions of the quantum and classical field theories of a single micro-state approximately agree at high occupancy, even in interacting systems. Furthermore, both quantum and classical field theories can thermalize, when appropriate coarse graining is introduced, with the classical case requiring a cutoff on low occupancy UV modes. We discuss applications of our results.

  11. Semi-classical analysis and pseudo-spectra

    NASA Astrophysics Data System (ADS)

    Davies, E. B.

    We prove an approximate spectral theorem for non-self-adjoint operators and investigate its applications to second-order differential operators in the semi-classical limit. This leads to the construction of a twisted FBI transform. We also investigate the connections between pseudo-spectra and boundary conditions in the semi-classical limit.

  12. Planck's radiation law: is a quantum-classical perspective possible?

    NASA Astrophysics Data System (ADS)

    Marrocco, Michele

    2016-05-01

    Planck's radiation law provides the solution to the blackbody problem that marks the decline of classical physics and the rise of the quantum theory of the radiation field. Here, we venture to suggest the possibility that classical physics might be equally suitable to deal with the blackbody problem. A classical version of the Planck's radiation law seems to be achievable if we learn from the quantum-classical correspondence between classical Mie theory and quantum-mechanical wave scattering from spherical scatterers (partial wave analysis). This correspondence designs a procedure for countable energy levels of the radiation trapped within the blackbody treated within the multipole approach of classical electrodynamics (in place of the customary and problematic expansion in terms of plane waves that give rise to the ultraviolet catastrophe). In turn, introducing the Boltzmann discretization of energy levels, the tools of classical thermodynamics and statistical theory become available for the task. On the other hand, the final result depends on a free parameter whose physical units are those of an action. Tuning this parameter on the value given by the Planck constant makes the classical result agree with the canonical Planck's radiation law.

  13. Supernovae in Binary Systems: An Application of Classical Mechanics.

    ERIC Educational Resources Information Center

    Mitalas, R.

    1980-01-01

    Presents the supernova explosion in a binary system as an application of classical mechanics. This presentation is intended to illustrate the power of the equivalent one-body problem and provide undergraduate students with a variety of insights into elementary classical mechanics. (HM)

  14. Cicero: A Framework for Multimedia Projects for Classics.

    ERIC Educational Resources Information Center

    Frischer, Bernard

    1986-01-01

    This paper focuses on a short term plan for a computerized multimedia expert system in the field of the classics that is under development at the University of California at Los Angeles. Noting both increased enrollments in classics courses and the problems associated with finding textbooks for courses in ancient civilizations that cover a variety…

  15. Close Relationship of Ruminant Pestiviruses and Classical Swine Fever Virus

    PubMed Central

    Postel, Alexander; Schmeiser, Stefanie; Oguzoglu, Tuba Cigdem; Indenbirken, Daniela; Alawi, Malik; Fischer, Nicole; Grundhoff, Adam

    2015-01-01

    To determine why serum from small ruminants infected with ruminant pestiviruses reacted positively to classical swine fever virus (CSFV)–specific diagnostic tests, we analyzed 2 pestiviruses from Turkey. They differed genetically and antigenically from known Pestivirus species and were closely related to CSFV. Cross-reactions would interfere with classical swine fever diagnosis in pigs. PMID:25811683

  16. The Classical Heritage in America: A Curriculum Resource. Tentative Edition.

    ERIC Educational Resources Information Center

    Philadelphia School District, PA. Office of Curriculum and Instruction.

    This curriculum resource is intended to help make students of Latin, Greek and other subjects more aware of America's classical heritage. It is designed to be used selectively by teachers to enrich the regular curriculum in classical languages in elementary and secondary schools. In providing background information for the teacher and suggestions…

  17. The Bernoulli or Coanda Conundrum and Other Classical Demonstration Myths

    NASA Astrophysics Data System (ADS)

    Stille, Dale

    2009-11-01

    Lecture Demonstration professionals have recently taken a closer look at demonstrations that were traditionally labeled ``Bernoulli Demonstrations'' in most textbooks. This examination has shown that in most cases the Coanda Effect, Magnus Effect, and Entrainment may be better explanations for most of these classic demonstrations. A discussion of other similarly classic demonstrations and some of their problems or misconceptions will also be presented.

  18. A Guide to Classical Liberal Scholarship. Revised Edition.

    ERIC Educational Resources Information Center

    Palmer, Tom G.

    This booklet introduces students to a wide range of works of classical liberal scholarship. The works described can be used in researching term papers, theses, and dissertations; each book and article provides valuable insights and information that can make the difference between an "A" and a "B" paper. The tradition of classical liberalism…

  19. Isochronous classical systems and quantum systems with equally spaced spectra

    NASA Astrophysics Data System (ADS)

    Cariñena, J. F.; Perelomov, A. M.; Rañada, M. F.

    2007-11-01

    We study isoperiodic classical systems, what allows us to find the classical isochronous systems, i.e. having a period independent of the energy. The corresponding quantum analog, systems with an equally spaced spectrum are analysed by looking for possible creation-like differential operators. The harmonic oscillator and the isotonic oscillator are the two main essentially unique examples of such situation.

  20. North Indian Classical Vocal Music for the Classroom

    ERIC Educational Resources Information Center

    Arya, Divya D.

    2015-01-01

    This article offers information that will allow music educators to incorporate North Indian classical vocal music into a multicultural music education curriculum. Obstacles to teaching North Indian classical vocal music are acknowledged, including lack of familiarity with the cultural/structural elements and challenges in teaching ear training and…

  1. Classical stabilization of the hydrogen atom in a monochromatic field

    SciTech Connect

    Benvenuto, F.; Casati, G. ); Shepelyansky, D.L. )

    1993-02-01

    We report the results of analytical and numerical investigations on the ionization of a classical atom in a strong, linearly polarized, monochromatic field. We show that the ionization probability decreases with increasing field intensity at field amplitudes much larger than the classical chaos border. This effect should be observable in real laboratory experiments.

  2. Turning Points in the Development of Classical Musicians

    ERIC Educational Resources Information Center

    Gabor, Elena

    2011-01-01

    This qualitative study investigated the vocational socialization turning points in families of classical musicians. I sampled and interviewed 20 parent-child dyads, for a total of 46 interviews. Data analysis revealed that classical musicians' experiences were marked by 11 turning points that affected their identification with the occupation:…

  3. Introduction to Classical Density Functional Theory by a Computational Experiment

    ERIC Educational Resources Information Center

    Jeanmairet, Guillaume; Levy, Nicolas; Levesque, Maximilien; Borgis, Daniel

    2014-01-01

    We propose an in silico experiment to introduce the classical density functional theory (cDFT). Density functional theories, whether quantum or classical, rely on abstract concepts that are nonintuitive; however, they are at the heart of powerful tools and active fields of research in both physics and chemistry. They led to the 1998 Nobel Prize in…

  4. German Children's Classics: Heirs and Pretenders to an Eclectic Heritage

    ERIC Educational Resources Information Center

    Doderer, Klaus

    1973-01-01

    There are no classic children's books, if by classics we mean books that will last forever. Instead, it is a matter of constant reevaluation. At most, we have older works that are still valuable today because they touch upon the human and artistic problems of our time. (Author/SJ)

  5. Supplemental Reading for Ninth Graders: Classic or Young Adult Literature

    ERIC Educational Resources Information Center

    Hill, Katherine Jane Roney

    2012-01-01

    The project addressed the debate over supplemental literature: young adult or classic selections to better support teaching ninth graders Tennessee's English I curriculum standards. Research supported both classical and contemporary literature for teaching ninth graders, making it difficult to determine which type of literature might produce the…

  6. Geometric angles in cyclic evolutions of a classical system

    NASA Technical Reports Server (NTRS)

    Bhattacharjee, A.; Sen, Tanaji

    1988-01-01

    A perturbative method, using Lie transforms, is given for calculating the Hannay angle for slow, cyclic evolutions of a classical system, taking into account the finite rate of change of the Hamiltonian. The method is applied to the generalized harmonic oscillator. The classical Aharonov-Anandan angle is also calculated. The interpretational ambiguity in the definitions of geometrical angles is discussed.

  7. Quantum dynamics in open quantum-classical systems.

    PubMed

    Kapral, Raymond

    2015-02-25

    Often quantum systems are not isolated and interactions with their environments must be taken into account. In such open quantum systems these environmental interactions can lead to decoherence and dissipation, which have a marked influence on the properties of the quantum system. In many instances the environment is well-approximated by classical mechanics, so that one is led to consider the dynamics of open quantum-classical systems. Since a full quantum dynamical description of large many-body systems is not currently feasible, mixed quantum-classical methods can provide accurate and computationally tractable ways to follow the dynamics of both the system and its environment. This review focuses on quantum-classical Liouville dynamics, one of several quantum-classical descriptions, and discusses the problems that arise when one attempts to combine quantum and classical mechanics, coherence and decoherence in quantum-classical systems, nonadiabatic dynamics, surface-hopping and mean-field theories and their relation to quantum-classical Liouville dynamics, as well as methods for simulating the dynamics.

  8. The Aharonov-Bohm effect and classical potentials

    SciTech Connect

    Mijatovic, M.; Trencevski, K.; Veljanoski, B.

    1993-06-01

    Using the inverse scattering method we derive the classical potential which produces the same cross section as the Ahaxonov-Bohm effect. Because the potential is velocity dependent it shows that this effect of quantum scattering theory can reduce to non-potential classical mechanics, only. 7 refs., 3 figs.

  9. The Statistical Interpretation of Classical Thermodynamic Heating and Expansion Processes

    ERIC Educational Resources Information Center

    Cartier, Stephen F.

    2011-01-01

    A statistical model has been developed and applied to interpret thermodynamic processes typically presented from the macroscopic, classical perspective. Through this model, students learn and apply the concepts of statistical mechanics, quantum mechanics, and classical thermodynamics in the analysis of the (i) constant volume heating, (ii)…

  10. Classical system boundaries cannot be determined within quantum Darwinism

    NASA Astrophysics Data System (ADS)

    Fields, Chris

    Multiple observers who interact with environmental encodings of the states of a macroscopic quantum system S as required by quantum Darwinism cannot demonstrate that they are jointly observing S without a joint a priori assumption of a classical boundary separating S from its environment E. Quantum Darwinism cannot, therefore, be regarded as providing a purely quantum-mechanical explanation of the "emergence" of classicality.

  11. Quantum mechanical ground state of hydrogen obtained from classical electrodynamics

    NASA Astrophysics Data System (ADS)

    Cole, Daniel C.; Zou, Yi

    2003-10-01

    The behavior of a classical charged point particle under the influence of only a Coulombic binding potential and classical electromagnetic zero-point radiation, is shown to agree closely with the probability density distribution of Schrödinger's wave equation for the ground state of hydrogen. These results again raise the possibility that the main tenets of stochastic electrodynamics (SED) are correct.

  12. "Antigone" on the Night Shift: Classics in the Contemporary Classroom.

    ERIC Educational Resources Information Center

    Devenish, Alan

    2000-01-01

    Examines community college students' choices of favorite works after a one-year composition and literature course. Finds "Antigone" was the favorite. Claims Greek classical works put students in contact with a distant culture that they find intriguing. Suggests juxtaposing a classical work with one from another time and culture to avoid…

  13. Inexpensive Books for Teaching the Classics: 19th Annual List.

    ERIC Educational Resources Information Center

    Schoenheim, Ursula

    1968-01-01

    All the materials in this bibliography are designed for use in courses in classical literature in translation, classical civilization, and for supplementary reading in Latin and Greek courses. All the books are in English and are meant for grade levels seven and above. Books are grouped under subheadings which include (1) Authors, Texts,…

  14. Redundant Information and the Quantum-Classical Transition

    ERIC Educational Resources Information Center

    Riedel, Charles Jess

    2012-01-01

    A state selected at random from the Hilbert space of a many-body system is overwhelmingly likely to exhibit highly non-classical correlations. For these typical states, half of the environment must be measured by an observer to determine the state of a given subsystem. The objectivity of classical reality--the fact that multiple observers can each…

  15. [Mental disease in two classical music composers].

    PubMed

    Rempelakos, L; Poulakou-Rebelakou, E; Ploumpidis, D

    2012-01-01

    A study οn two neglected classical music composers suffering a not syphilitic mental disease, is attempted here, syphilis of the central nervous system being frequent in that time. A brief overview on the psychiatric ailments of many great composers reveals suicide attempts and more or less severe depression following external events. The issue of a possible relationship between mental disease and (musical) creativity can be discussed, as mood swings and a certain tendency to melancholia are frequent features of a talented brain (a fact that can also be detected in their works). The first case presented here is Hans Rott from Austria, the beloved student of Anton Bruckner, who was considered to be at least equal to his famous classmate Gustav Mahler. The great expectations of his teacher and his friends suddenly came to an end, when he suffered a crisis of schizophrenia and was hospitalized in an insane asylum in Lower Austria. The tragic psychiatric adventure of the young musician lasted almost four years. He was diagnosed as a case of "hallucinatory insanity" and "persecution mania" by the medical staff, before dying of tuberculosis, aged only 26, and having completed only one symphony and several smaller works. His name came again on surface only a century after his death, when in 1989 his Symphony in E Major was discovered and premiered with great success, permitting to its creator a posthumous recognition, among Bruckner and Mahler. The second case of mental illness is that of the Armenian Komitas Vardapet. He was an orphan who grew up in theological schools and became a monk and later a priest, though he spent some years in Berlin in order to develop his musical skills. He is considered to be an authority of Armenian ecclesiastic music, introducing polyphony in the Armenian Church's music and collecting numerous traditional songs from all parts of Armenia. In 1915, during the Armenian genocide he was deported, tortured but finally saved, due to interventions

  16. Drumlins: A Classic Example of Pattern Formation.

    NASA Astrophysics Data System (ADS)

    Ely, Jeremy C.; Clark, Chris D.; Spagnolo, Matteo; Hahn, Ute; Hughes, Anna L. C.

    2014-05-01

    geomorphic phenomena can be equally attributed to drumlins and other subglacial bedforms, providing a conceptual framework for understanding their formation. Equally, we suggest that drumlins represent a classic example of pattern formation within the geosciences, and hence provide exciting opportunities for studying the dynamics of pattern formation.

  17. Simultaneous classical communication and quantum key distribution using continuous variables*

    NASA Astrophysics Data System (ADS)

    Qi, Bing

    2016-10-01

    Presently, classical optical communication systems employing strong laser pulses and quantum key distribution (QKD) systems working at single-photon levels are very different communication modalities. Dedicated devices are commonly required to implement QKD. In this paper, we propose a scheme which allows classical communication and QKD to be implemented simultaneously using the same communication infrastructure. More specially, we propose a coherent communication scheme where both the bits for classical communication and the Gaussian distributed random numbers for QKD are encoded on the same weak coherent pulse and decoded by the same coherent receiver. Simulation results based on practical system parameters show that both deterministic classical communication with a bit error rate of 10-9 and secure key distribution could be achieved over tens of kilometers of single-mode fibers. It is conceivable that in the future coherent optical communication network, QKD will be operated in the background of classical communication at a minimal cost.

  18. Simultaneous classical communication and quantum key distribution using continuous variables

    SciTech Connect

    Qi, Bing

    2016-10-26

    Currently, classical optical communication systems employing strong laser pulses and quantum key distribution (QKD) systems working at single-photon levels are very different communication modalities. Dedicated devices are commonly required to implement QKD. In this paper, we propose a scheme which allows classical communication and QKD to be implemented simultaneously using the same communication infrastructure. More specially, we propose a coherent communication scheme where both the bits for classical communication and the Gaussian distributed random numbers for QKD are encoded on the same weak coherent pulse and decoded by the same coherent receiver. Simulation results based on practical system parameters show that both deterministic classical communication with a bit error rate of 10–9 and secure key distribution could be achieved over tens of kilometers of single-mode fibers. It is conceivable that in the future coherent optical communication network, QKD will be operated in the background of classical communication at a minimal cost.

  19. Heterotic quantum and classical computing on convergence spaces

    NASA Astrophysics Data System (ADS)

    Patten, D. R.; Jakel, D. W.; Irwin, R. J.; Blair, H. A.

    2015-05-01

    Category-theoretic characterizations of heterotic models of computation, introduced by Stepney et al., combine computational models such as classical/quantum, digital/analog, synchronous/asynchronous, etc. to obtain increased computational power. A highly informative classical/quantum heterotic model of computation is represented by Abramsky's simple sequential imperative quantum programming language which extends the classical simple imperative programming language to encompass quantum computation. The mathematical (denotational) semantics of this classical language serves as a basic foundation upon which formal verification methods can be developed. We present a more comprehensive heterotic classical/quantum model of computation based on heterotic dynamical systems on convergence spaces. Convergence spaces subsume topological spaces but admit finer structure from which, in prior work, we obtained differential calculi in the cartesian closed category of convergence spaces allowing us to define heterotic dynamical systems, given by coupled systems of first order differential equations whose variables are functions from the reals to convergence spaces.

  20. Foucault's pendulum, a classical analog for the electron spin state

    NASA Astrophysics Data System (ADS)

    Linck, Rebecca A.

    Spin has long been regarded as a fundamentally quantum phenomena that is incapable of being described classically. To bridge the gap and show that aspects of spin's quantum nature can be described classically, this work uses a classical Lagrangian based on the coupled oscillations of Foucault's pendulum as an analog for the electron spin state in an external magnetic field. With this analog it is possible to demonstrate that Foucault's pendulum not only serves as a basis for explaining geometric phase, but is also a basis for reproducing a broad range of behavior from Zeeman-like frequency splitting to precession of the spin state. By demonstrating that unmeasured electron spin states can be fully described in classical terms, this research opens the door to using the tools of classical physics to examine an inherently quantum phenomenon.

  1. Proton transport in barium stannate: classical, semi-classical and quantum regimes.

    PubMed

    Geneste, Grégory; Ottochian, Alistar; Hermet, Jessica; Dezanneau, Guilhem

    2015-07-15

    Density-functional theory calculations are performed to investigate proton transport in BaSnO3. Structural optimizations in the stable and saddle point configurations for transfer (hopping) and reorientation allow description of the high-temperature classical and semi-classical regimes, in which diffusion occurs by over-barrier motion. At lower temperature (typically below 300 K), we describe the thermally-assisted quantum regime, in which protonic motion is of quantum nature and occurs in "coincidence" configurations favored by thermal fluctuations of the surrounding atoms. Both the non-adiabatic and the adiabatic limits are examined. In the adiabatic limit, the protonic energy landscape in the coincidence configuration is very flat. Path-integral molecular dynamics simulations of the proton in the coincidence potential reveal, in the transfer case, that the density of probability of H(+) has its maximum at the saddle point, because the zero-point energy exceeds the coincidence barrier. Arguments are given that support the adiabatic picture for the transfer mechanism. In the case of reorientation, the time scales for the existence of the coincidence and for protonic motion, as estimated from the time-energy uncertainty principle by using a simple one-dimensional model, are of the same order of magnitude, suggesting that the adiabatic limit is not reached. Protonic transfer and reorientation in this oxide are therefore governed by different mechanisms below room temperature.

  2. Comparison of the transcriptional regulation of classical and non-classical MHC class II genes.

    PubMed

    Hake, Sandra B; Tobin, Helen M; Steimle, Viktor; Denzin, Lisa K

    2003-09-01

    The class II transactivator (CIITA) regulates expression of the classical and non-classical MHC class II genes, HLA-DR, -DP, -DQ and -DM, but not the B cell-specific HLA-DO (DO). Here we show that only HLA-DR expression is completely dependent on CIITA, since residual expression of HLA-DM, -DP and the beta chain of DQ was observed in CIITA-deficient RJ2.2.5 cells. Although DO shows a unique expression pattern compared to other MHC class II genes, prolonged IFN-gamma treatment of HeLa cells induced DOB expression. Similar to all MHC class II promoters, the DOB promoter contains the highly conserved W, X1, and Y boxes in addition to a putative OCT box. Mutational analysis of the DOB promoter demonstrated that the X1, Y and OCT boxes are necessary for maximum promoter activity.Furthermore, our results demonstrate that CREB-1, RFXANK and Oct-2 occupy the DOB promoter in vivo, However, CIITA and Bob-1 were only minimally recruited. Finally, fusion of Bjab, a DOB-negative B cell line, with.174 B cells that lack the complete MHC class II region (including the DO genes), lead to DO expression. These data indicate that the expression of DO is regulated by an unidentified factor in B cells.

  3. Prequantum Classical Statistical Field Theory: Schrödinger Dynamics of Entangled Systems as a Classical Stochastic Process

    NASA Astrophysics Data System (ADS)

    Khrennikov, Andrei

    2011-03-01

    The idea that quantum randomness can be reduced to randomness of classical fields (fluctuating at time and space scales which are essentially finer than scales approachable in modern quantum experiments) is rather old. Various models have been proposed, e.g., stochastic electrodynamics or the semiclassical model. Recently a new model, so called prequantum classical statistical field theory (PCSFT), was developed. By this model a "quantum system" is just a label for (so to say "prequantum") classical random field. Quantum averages can be represented as classical field averages. Correlations between observables on subsystems of a composite system can be as well represented as classical correlations. In particular, it can be done for entangled systems. Creation of such classical field representation demystifies quantum entanglement. In this paper we show that quantum dynamics (given by Schrödinger's equation) of entangled systems can be represented as the stochastic dynamics of classical random fields. The "effect of entanglement" is produced by classical correlations which were present at the initial moment of time, cf. views of Albert Einstein.

  4. Prime Contract Awards by State or Country, Place and Contractor. Part 10 (Royal Oak, Michigan - Garwood, New Jersey), FY1991

    DTIC Science & Technology

    1991-01-01

    1.0 o M> Ŕ 1o Xc x110 12-I )4 - NNN " N N ( (0 1 1 u 1 )Ch nOn (A V) CAOU) on n cCO LL ON 00 N M CON 1 CL is 4I 0O-4 ൈ_) 0OU. 002AU. LL. LA- 00 0...N 1411 4( NJ.- 0 44 (0 C atN 4x 4ɜ gi Is4’) CoN L * q .-CŔi 000 0 N I04C)0 0 00 0N11 N 0-40 N < << < if O-o. of QNc -C c N 0(4r N N~ co Nn NON N( N...3 .I004 101 04e N- N- N. NN N N N N N 0 I E0 1 00 4 0 0. 0" C0 I-0 CA 0 000000 00 m0 0 0 0 00 (01 it M 0I CON ’It-40 a -- -4 on -g (0. 1r-0-- - Cr- 1

  5. The Thermodynamics Of Calcite Nucleation On Organic Surfaces: Classical Vs. Non-Classical Pathways

    NASA Astrophysics Data System (ADS)

    Nielsen, M.; Hu, Q.; Hamm, L. M.; Lee, J. R.; Becker, U.; Dove, P. M.; De Yoreo, J.

    2012-12-01

    Nucleation in the natural world often occurs at organic surfaces. During biomineralization, living organisms use macromolecular matrices to direct nucleation of a variety of inorganic materials by controlling the timing, polymorphism, morphology, and crystallographic orientation of mineral nuclei. In geochemical settings, mineral surfaces, which are often covered with organic layers or biofilms, surround the volume within which nucleation occurs. Despite the importance of nucleation phenomena in these natural settings, our understanding of the reaction dynamics and energetics of the process is limited. Issues such as the role of pre-nucleation clusters, formation of amorphous precursors, and polymorph selection during the initial stages of nucleation, as well as the structural relationships between the organic matrix and the emerging nucleus are poorly understood. Using self-assembled monolayers (SAMs) of alkanethiols as simple models for macromolecular matrices and organic films, we address the gaps in our understanding by employing a suite of in situ methods to investigate CaCO3 nucleation. From optical measurements of calcite nucleation rates on alkanethiol SAMs, we find that for two carboxyl-terminated alkanethiol SAMs with odd (mercaptoundecanoic acid) and even (mercaptohexadecanoic acid) carbon chains, the rate exhibits the supersaturation dependence expected from classical theory and the effective interfacial energy is reduced from about 109 mJ/m2 in bulk solution to 81 mJ/m2 and 72 mJ/m2, respectively. Theoretical analysis shows that the corresponding free energy barrier is reduced from 105kT for homogeneous nucleation in bulk solution to 27KT and 19kT, respectively. The results demonstrate that calcite nucleation on these carboxyl SAMs is described well in purely classical terms through a reduction in the thermodynamic barrier due to decreased interfacial free energy. In addition, although amorphous particles form prior to crystal nucleation on hydroxyl

  6. The new classic data acquisition system for NPOI

    NASA Astrophysics Data System (ADS)

    Sun, B.; Jorgensen, A. M.; Landavazo, M.; Hutter, D. J.; van Belle, G. T.; Mozurkewich, David; Armstrong, J. T.; Schmitt, H. R.; Baines, E. K.; Restaino, S. R.

    2014-07-01

    The New Classic data acquisition system is an important portion of a new project of stellar surface imaging with the NPOI, funded by the National Science Foundation, and enables the data acquisition necessary for the project. The NPOI can simultaneously deliver beams from 6 telescopes to the beam combining facility, and in the Classic beam combiner these are combined 4 at a time on 3 separate spectrographs with all 15 possible baselines observed. The Classic data acquisition system is limited to 16 of 32 wavelength channels on two spectrographs and limited to 30 s integrations followed by a pause to ush data. Classic also has some limitations in its fringe-tracking capability. These factors, and the fact that Classic incorporates 1990s technology which cannot be easily replaced are motivation for upgrading the data acquisition system. The New Classic data acquisition system is based around modern electronics, including a high-end Stratix FPGA, a 200 MB/s Direct Memory Access card, and a fast modern Linux computer. These allow for continuous recording of all 96 channels across three spectrographs, increasing the total amount of data recorded by a an estimated order of magnitude. The additional computing power on the data acquisition system also allows for the implementation of more sophisticated fringe-tracking algorithms which are needed for the Stellar Surface Imaging project. In this paper we describe the New Classic system design and implementation, describe the background and motivation for the system as well as show some initial results from using it.

  7. COLORS OF INNER DISK CLASSICAL KUIPER BELT OBJECTS

    SciTech Connect

    Romanishin, W.; Tegler, S. C.; Consolmagno, G. J. E-mail: Stephen.Tegler@nau.ed

    2010-07-15

    We present new optical broadband colors, obtained with the Keck 1 and Vatican Advanced Technology telescopes, for six objects in the inner classical Kuiper Belt. Objects in the inner classical Kuiper Belt are of interest as they may represent the surviving members of the primordial Kuiper Belt that formed interior to the current position of the 3:2 resonance with Neptune, the current position of the plutinos, or, alternatively, they may be objects formed at a different heliocentric distance that were then moved to their present locations. The six new colors, combined with four previously published, show that the ten inner belt objects with known colors form a neutral clump and a reddish clump in B-R color. Nonparametric statistical tests show no significant difference between the B-R color distribution of the inner disk objects compared to the color distributions of Centaurs, plutinos, or scattered disk objects. However, the B-R color distribution of the inner classical Kuiper Belt Objects does differ significantly from the distribution of colors in the cold (low inclination) main classical Kuiper Belt. The cold main classical objects are predominately red, while the inner classical belt objects are a mixture of neutral and red. The color difference may reveal the existence of a gradient in the composition and/or surface processing history in the primordial Kuiper Belt, or indicate that the inner disk objects are not dynamically analogous to the cold main classical belt objects.

  8. A wave equation interpolating between classical and quantum mechanics

    NASA Astrophysics Data System (ADS)

    Schleich, W. P.; Greenberger, D. M.; Kobe, D. H.; Scully, M. O.

    2015-10-01

    We derive a ‘master’ wave equation for a family of complex-valued waves {{Φ }}\\equiv R{exp}[{{{i}}S}({cl)}/{{\\hbar }}] whose phase dynamics is dictated by the Hamilton-Jacobi equation for the classical action {S}({cl)}. For a special choice of the dynamics of the amplitude R which eliminates all remnants of classical mechanics associated with {S}({cl)} our wave equation reduces to the Schrödinger equation. In this case the amplitude satisfies a Schrödinger equation analogous to that of a charged particle in an electromagnetic field where the roles of the scalar and the vector potentials are played by the classical energy and the momentum, respectively. In general this amplitude is complex and thereby creates in addition to the classical phase {S}({cl)}/{{\\hbar }} a quantum phase. Classical statistical mechanics, as described by a classical matter wave, follows from our wave equation when we choose the dynamics of the amplitude such that it remains real for all times. Our analysis shows that classical and quantum matter waves are distinguished by two different choices of the dynamics of their amplitudes rather than two values of Planck’s constant. We dedicate this paper to the memory of Richard Lewis Arnowitt—a pioneer of many-body theory, a path finder at the interface of gravity and quantum mechanics, and a true leader in non-relativistic and relativistic quantum field theory.

  9. The new classic instrument for the navy precision optical interferometer

    NASA Astrophysics Data System (ADS)

    Jorgensen, A. M.; Schmitt, H. R.; Armstrong, J. T.; Baines, E. K.; Hindsley, R.; Mozurkewich, D.; van Belle, G. T.

    2016-08-01

    The New Classic instrument was built as a electronics and computer upgrade to the existing Classic beam combiner at the Navy Precision Optical Interferometer (NPOI). The classic beam combiner is able to record 32 of 96 available channels and has a data throughput limitation which results in a low duty cycle. Additionally the computing power of the Classic system limited the amount of fringe tracking that was possible. The New Classic system implements a high-throughput data acquisition system which is capable of recording all 96 channels continuously. It also has a modern high-speed computer for data management and data processing. The computer is sufficiently powerful to implement more sophisticated fringe-tracking algorithms than the Classic system, including multi-baseline bootstrapping. In this paper we described the New Classic hardware and software, including the fringe-tracking algorithm, performance, and the user interface. We also show some initial results from the first 5-station, 4-baseline bootstrapping carried out in January 2015.

  10. Exploring the Boundaries of the Cold Classical Population

    NASA Astrophysics Data System (ADS)

    Grundy, Will; Brucker, Melissa; Levison, Hal; Mueller, Michael; Noll, Keith; Osip, David; Stansberry, John; Tegler, Steve

    2008-03-01

    Objects in the Cold Classical Kuiper belt exhibit distinctive physical characteristics from other members of the trans-neptunian swarm. These include higher albedos, more homogeneously red colors, smaller sizes, and higher rates of binarity. Spitzer is the premier facility for determining albedos of these distant objects, since it can detect more than one thermal wavelength, enabling otherwise crippling model uncertainties to be overcome. We propose to use Spitzer to study objects in dynamical regions near the Cold Classical belt to see if they too have high albedos, consistent with possible kinship with the Cold Classical population. Possible physical affiliations between these different dynamical classes could provide valuable constraints on dynamical models of the evolution of the outer Solar System. We request observations of five strategically selected targets. Two are part of the Inner Classical group, objects in otherwise Classical type orbits except that they are closer to the Sun than the 3:2 mean motion resonance with Neptune. Two are among the least excited occupants of the 2:1 mean motion resonance and one is among the least excited occupants of the 3:2 resonance. As Neptune migrated outward, these resonances could have transported objects outward and deposited them into the Cold Classical region. If so, we would expect their least excited members to share physical characteristics with the Cold Classical objects.

  11. Classical and quantum distinctions between weak and strong coupling

    NASA Astrophysics Data System (ADS)

    Rahimzadeh-Kalaleh Rodriguez, Said

    2016-03-01

    Coupled systems subject to dissipation exhibit two different regimes known as weak coupling and strong coupling. Two damped coupled harmonic oscillators (CHOs) constitute a model system where the key features of weak and strong coupling can be identified. Several of these features are common to classical and quantum systems, as a number of quantum-classical correspondences have shown. However, the condition defining the boundary between weak and strong coupling is distinct in classical and quantum formalisms. Here we describe the origin of two widely used definitions of strong coupling. Using a classical CHO model, we show that energy exchange cycles and avoided resonance crossings signal the onset of strong coupling according to one criterion. From the classical CHO model we derive a non-Hermitian Hamiltonian describing open quantum systems. Based on the analytic properties of the Hamiltonian, we identify the boundary between weak and strong coupling with a different feature: a non-Hermitian degeneracy known as the exceptional point. For certain parameter ranges the classical and quantum criterion for strong coupling coincide; for other ranges they do not. Examples of systems in strong coupling according to one or another criterion, but not both, are illustrated. The framework here presented is suitable for introducing graduate or advanced undegraduate students to the basic properties of strongly coupled systems, as well as to the similarities and subtle differences between classical and quantum descriptions of coupled dissipative systems.

  12. Classical controller design techniques for fractional order case.

    PubMed

    Yeroglu, Celaleddin; Tan, Nusret

    2011-07-01

    This paper presents some classical controller design techniques for the fractional order case. New robust lag, lag-lead, PI controller design methods for control systems with a fractional order interval transfer function (FOITF) are proposed using classical design methods with the Bode envelopes of the FOITF. These controllers satisfy the robust performance specifications of the fractional order interval plant. In order to design a classical PID controller, an optimization technique based on fractional order reference model is used. PID controller parameters are obtained using the least squares optimization method. Different PID controller parameters that satisfy stability have been obtained for the same plant.

  13. Quantum-Classical Correspondence of Shortcuts to Adiabaticity

    NASA Astrophysics Data System (ADS)

    Okuyama, Manaka; Takahashi, Kazutaka

    2017-04-01

    We formulate the theory of shortcuts to adiabaticity in classical mechanics. For a reference Hamiltonian, the counterdiabatic term is constructed from the dispersionless Korteweg-de Vries (KdV) hierarchy. Then the adiabatic theorem holds exactly for an arbitrary choice of time-dependent parameters. We use the Hamilton-Jacobi theory to define the generalized action. The action is independent of the history of the parameters and is directly related to the adiabatic invariant. The dispersionless KdV hierarchy is obtained from the classical limit of the KdV hierarchy for the quantum shortcuts to adiabaticity. This correspondence suggests some relation between the quantum and classical adiabatic theorems.

  14. Intricate Transcriptional Networks of Classical Brown and Beige Fat Cells.

    PubMed

    Park, Jun Hong; Hur, Wonhee; Lee, Sean Bong

    2015-01-01

    Brown adipocytes are a specialized cell type that is critical for adaptive thermogenesis, energy homeostasis, and metabolism. In response to cold, both classical brown fat and the newly identified "beige" or "brite" cells are activated by β-adrenergic signaling and catabolize stored lipids and carbohydrates to produce heat via UCP1. Once thought to be non-existent in adults, recent studies have discovered active classical brown and beige fat cells in humans, thus reinvigorating interest in brown and beige adipocytes. This review will focus on the newly discovered transcription factors and microRNAs that specify and orchestrate the classical brown and beige fat cell development.

  15. Classical Physics and the Bounds of Quantum Correlations.

    PubMed

    Frustaglia, Diego; Baltanás, José P; Velázquez-Ahumada, María C; Fernández-Prieto, Armando; Lujambio, Aintzane; Losada, Vicente; Freire, Manuel J; Cabello, Adán

    2016-06-24

    A unifying principle explaining the numerical bounds of quantum correlations remains elusive, despite the efforts devoted to identifying it. Here, we show that these bounds are indeed not exclusive to quantum theory: for any abstract correlation scenario with compatible measurements, models based on classical waves produce probability distributions indistinguishable from those of quantum theory and, therefore, share the same bounds. We demonstrate this finding by implementing classical microwaves that propagate along meter-size transmission-line circuits and reproduce the probabilities of three emblematic quantum experiments. Our results show that the "quantum" bounds would also occur in a classical universe without quanta. The implications of this observation are discussed.

  16. First Principals and Classical Molecular Dynamics Simulations of Solvated Benzene

    SciTech Connect

    Allesch, M; Lightstone, F; Schwegler, E; Galli, G

    2007-09-11

    We have performed extensive ab initio and classical MD simulations of benzene in water in order to examine the unique solvation structures that are formed. Qualitative differences between classical and ab initio MD simulations are found and the importance of various technical simulation parameters is examined. Our comparison indicates that non-polarizable classical models are not capable of describing the solute-water interface correctly if local interactions become energetically comparable to water hydrogen bonds. In addition, a comparison is made between a rigid water model and fully flexible water within ab initio MD simulations which shows that both models agree qualitatively for this challenging system.

  17. Statistical mechanics based on fractional classical and quantum mechanics

    SciTech Connect

    Korichi, Z.; Meftah, M. T.

    2014-03-15

    The purpose of this work is to study some problems in statistical mechanics based on the fractional classical and quantum mechanics. At first stage we have presented the thermodynamical properties of the classical ideal gas and the system of N classical oscillators. In both cases, the Hamiltonian contains fractional exponents of the phase space (position and momentum). At the second stage, in the context of the fractional quantum mechanics, we have calculated the thermodynamical properties for the black body radiation, studied the Bose-Einstein statistics with the related problem of the condensation and the Fermi-Dirac statistics.

  18. Classical models of the spin 1/2 system

    NASA Astrophysics Data System (ADS)

    Salazar-Lazaro, Carlos H.

    We proposed a Quaternionic mechanical system motivated by the Foucault pendulum as a classical model for the dynamics of the spin ½ system. We showed that this mechanical system contains the dynamics of the spin state of the electron under a uniform magnetic field as it is given by the Schrodinger-Pauli-Equation (SPE). We closed with a characterization of the dynamics of this generalized classical system by showing that it is equivalent with the dynamics of the Schrodinger Pauli Equation as long as the solutions to the generalized classical system are roots of the Lagrangian, that is the condition L = 0 holds.

  19. Averaged energy inequalities for the nonminimally coupled classical scalar field

    SciTech Connect

    Fewster, Christopher J.; Osterbrink, Lutz W.

    2006-08-15

    The stress-energy tensor for the classical nonminimally coupled scalar field is known not to satisfy the pointwise energy conditions of general relativity. In this paper we show, however, that local averages of the classical stress-energy tensor satisfy certain inequalities. We give bounds for averages along causal geodesics and show, e.g., that in Ricci-flat background spacetimes, ANEC and AWEC are satisfied. Furthermore we use our result to show that in the classical situation we have an analogue to the phenomenon of quantum interest. These results lay the foundations for analogous energy inequalities for the quantized nonminimally coupled fields, which will be discussed elsewhere.

  20. Secure Communication via a Recycling of Attenuated Classical Signals

    NASA Astrophysics Data System (ADS)

    Smith, A. Matthew

    2017-01-01

    We describe a simple method of interleaving a classical and quantum signal in a secure communication system at a single wavelength. The system transmits data encrypted via a one-time pad on a classical signal and produces a single-photon reflection of the encrypted signal. This attenuated signal can be used to observe eavesdroppers and produce fresh secret bits. The system can be secured against eavesdroppers, detect simple tampering or classical bit errors, produces more secret bits than it consumes, and does not require any entanglement or complex wavelength division multiplexing, thus, making continuous secure two-way communication via one-time pads practical.

  1. Universal local symmetries and nonsuperposition in classical mechanics.

    PubMed

    Gozzi, Ennio; Pagani, Carlo

    2010-10-08

    In the Hilbert space formulation of classical mechanics, pioneered by Koopman and von Neumann, there are potentially more observables than in the standard approach to classical mechanics. In this Letter, we show that actually many of those extra observables are not invariant under a set of universal local symmetries which appear once the Koopman and von Neumann formulation is extended to include the evolution of differential forms. Because of their noninvariance, those extra observables have to be removed. This removal makes the superposition of states in the Koopman and von Neumann formulation, and as a consequence also in classical mechanics, impossible.

  2. Models on the boundary between classical and quantum mechanics.

    PubMed

    Hooft, Gerard 't

    2015-08-06

    Arguments that quantum mechanics cannot be explained in terms of any classical theory using only classical logic seem to be based on sound mathematical considerations: there cannot be physical laws that require 'conspiracy'. It may therefore be surprising that there are several explicit quantum systems where these considerations apparently do not apply. In this report, several such counterexamples are shown. These are quantum models that do have a classical origin. The most curious of these models is superstring theory. So now the question is asked: how can such a model feature 'conspiracy', and how bad is that? Is there conspiracy in the vacuum fluctuations? Arguments concerning Bell's theorem are further sharpened.

  3. Secure Communication via a Recycling of Attenuated Classical Signals

    DOE PAGES

    Smith, IV, Amos M.

    2017-01-12

    We describe a simple method of interleaving a classical and quantum signal in a secure communication system at a single wavelength. The system transmits data encrypted via a one-time pad on a classical signal and produces a single-photon reflection of the encrypted signal. This attenuated signal can be used to observe eavesdroppers and produce fresh secret bits. The system can be secured against eavesdroppers, detect simple tampering or classical bit errors, produces more secret bits than it consumes, and does not require any entanglement or complex wavelength division multiplexing, thus, making continuous secure two-way communication via one-time pads practical.

  4. Classical-physics applications for Finsler b space

    NASA Astrophysics Data System (ADS)

    Foster, Joshua; Lehnert, Ralf

    2015-06-01

    The classical propagation of certain Lorentz-violating fermions is known to be governed by geodesics of a four-dimensional pseudo-Finsler b space parametrized by a prescribed background covector field. This work identifies systems in classical physics that are governed by the three-dimensional version of Finsler b space and constructs a geodesic for a sample non-constant choice for the background covector. The existence of these classical analogues demonstrates that Finsler b spaces possess applications in conventional physics, which may yield insight into the propagation of SME fermions on curved manifolds.

  5. Transposon-facilitated recombination in classical biotypes of Vibrio cholerae.

    PubMed Central

    Sublett, R D; Romig, W R

    1981-01-01

    Transposon-facilitated recombination (Tfr) donors of classical Vibrio cholerae strain 162 were constructed by introducing the ampicillin transposon Tn1 into the P conjugative plasmid and the bacterial chromosome. The improved donors mediated high-frequency, polarized transfer of chromosomal genes from origins to confirm the gene orders of the previous classical strain 162 genetic map and to establish its circularity. Significant transfer of linked genes from E1 Tor Tfr donors to classical recipients was demonstrated, and other evidence for genetic relatedness of these two V. cholerae biotypes is discussed. PMID:6265372

  6. Turning big bang into big bounce. I. Classical dynamics

    SciTech Connect

    Dzierzak, Piotr; Malkiewicz, Przemyslaw; Piechocki, Wlodzimierz

    2009-11-15

    The big bounce (BB) transition within a flat Friedmann-Robertson-Walker model is analyzed in the setting of loop geometry underlying the loop cosmology. We solve the constraint of the theory at the classical level to identify physical phase space and find the Lie algebra of the Dirac observables. We express energy density of matter and geometrical functions in terms of the observables. It is the modification of classical theory by the loop geometry that is responsible for BB. The classical energy scale specific to BB depends on a parameter that should be fixed either by cosmological data or determined theoretically at quantum level, otherwise the energy scale stays unknown.

  7. PREFACE: Particles and Fields: Classical and Quantum

    NASA Astrophysics Data System (ADS)

    Asorey, M.; Clemente-Gallardo, J.; Marmo, G.

    2007-07-01

    This volume contains some of the contributions to the Conference Particles and Fields: Classical and Quantum, which was held at Jaca (Spain) in September 2006 to honour George Sudarshan on his 75th birthday. Former and current students, associates and friends came to Jaca to share a few wonderful days with George and his family and to present some contributions of their present work as influenced by George's impressive achievements. This book summarizes those scientific contributions which are presented as a modest homage to the master, collaborator and friend. At the social ceremonies various speakers were able to recall instances of his life-long activity in India, the United States and Europe, adding colourful remarks on the friendly and intense atmosphere which surrounded those collaborations, some of which continued for several decades. This meeting would not have been possible without the financial support of several institutions. We are deeply indebted to Universidad de Zaragoza, Ministerio de Educación y Ciencia de España (CICYT), Departamento de Ciencia, Tecnología y Universidad del Gobierno de Aragón, Universitá di Napoli 'Federico II' and Istituto Nazionale di Fisica Nucleare. Finally, we would like to thank the participants, and particularly George's family, for their contribution to the wonderful atmosphere achieved during the Conference. We would like also to acknowledge the authors of the papers collected in the present volume, the members of the Scientific Committee for their guidance and support and the referees for their generous work. M Asorey, J Clemente-Gallardo and G Marmo The Local Organizing Committee George Sudarshan George Sudarshan

    International Advisory Committee

    A. Ashtekhar (Pennsylvania State University, USA)
    L. J. Boya (Universidad de Zaragoza, Spain)
    I. Cirac (Max Planck Institute, Garching

  8. Experimental device-independent tests of classical and quantum dimensions

    NASA Astrophysics Data System (ADS)

    Ahrens, Johan; Badziag, Piotr; Cabello, Adán; Bourennane, Mohamed

    2012-08-01

    A fundamental resource in any communication and computation task is the amount of information that can be transmitted and processed. The classical information encoded in a set of states is limited by the number of distinguishable states or classical dimension dc of the set. The sets used in quantum communication and information processing contain states that are neither identical nor distinguishable, and the quantum dimension dq of the set is the dimension of the Hilbert space spanned by these states. An important challenge is to assess the (classical or quantum) dimension of a set of states in a device-independent way, that is, without referring to the internal working of the device generating the states. Here we experimentally test dimension witnesses designed to efficiently determine the minimum dimension of sets of (three or four) photonic states from the correlations originated from measurements on them, and distinguish between classical and quantum sets of states.

  9. Quantum and classical operational complementarity for single systems

    SciTech Connect

    Luis, Alfredo

    2005-07-15

    We investigate duality relations between conjugate observables after measurements performed on a single realization of the system. The application of standard inference methods implies the existence of duality relations for single systems when using classical as well as quantum physics.

  10. Identifying the Stern-Gerlach force of classical electron dynamics

    PubMed Central

    Wen, Meng; Bauke, Heiko; Keitel, Christoph H.

    2016-01-01

    Different classical theories are commonly applied in various branches of physics to describe the relativistic dynamics of electrons by coupled equations for the orbital motion and spin precession. Exemplarily, we benchmark the Frenkel model and the classical Foldy-Wouthuysen model with spin-dependent forces (Stern-Gerlach forces) to the quantum dynamics as predicted by the Dirac equation. Both classical theories can lead to different or even contradicting predictions how the Stern-Gerlach forces modify the electron’s orbital motion, when the electron moves in strong electromagnetic field configurations of emerging high-intensity laser facilities. In this way, one may evaluate the validity and identify the limits of these classical theories via a comparison with possible experiments to provide a proper description of spin-induced dynamics. Our results indicate that the Foldy-Wouthuysen model is qualitatively in better agreement with the Dirac theory than the widely used Frenkel model. PMID:27546820

  11. The CLASSIC/CLIMB Data Reduction: The Software

    NASA Astrophysics Data System (ADS)

    ten Brummelaar, T.

    2014-09-01

    This is one of two chapters that describe the methods used to extract closure phase from CLIMB data and visibility amplitude from both the CLASSIC and CLIMB beam combiners. In this, the second chapter, I describe the pipeline software.

  12. A Unified Mathematical Definition of Classical Information Retrieval.

    ERIC Educational Resources Information Center

    Dominich, Sandor

    2000-01-01

    Presents a unified mathematical definition for the classical models of information retrieval and identifies a mathematical structure behind relevance feedback. Highlights include vector information retrieval; probabilistic information retrieval; and similarity information retrieval. (Contains 118 references.) (Author/LRW)

  13. Experimental assessment of unvalidated assumptions in classical plasticity theory.

    SciTech Connect

    Brannon, Rebecca Moss; Burghardt, Jeffrey A.; Bauer, Stephen J.; Bronowski, David R.

    2009-01-01

    This report investigates the validity of several key assumptions in classical plasticity theory regarding material response to changes in the loading direction. Three metals, two rock types, and one ceramic were subjected to non-standard loading directions, and the resulting strain response increments were displayed in Gudehus diagrams to illustrate the approximation error of classical plasticity theories. A rigorous mathematical framework for fitting classical theories to the data, thus quantifying the error, is provided. Further data analysis techniques are presented that allow testing for the effect of changes in loading direction without having to use a new sample and for inferring the yield normal and flow directions without having to measure the yield surface. Though the data are inconclusive, there is indication that classical, incrementally linear, plasticity theory may be inadequate over a certain range of loading directions. This range of loading directions also coincides with loading directions that are known to produce a physically inadmissible instability for any nonassociative plasticity model.

  14. Strong Analog Classical Simulation of Coherent Quantum Dynamics

    NASA Astrophysics Data System (ADS)

    Wang, Dong-Sheng

    2017-02-01

    A strong analog classical simulation of general quantum evolution is proposed, which serves as a novel scheme in quantum computation and simulation. The scheme employs the approach of geometric quantum mechanics and quantum informational technique of quantum tomography, which applies broadly to cases of mixed states, nonunitary evolution, and infinite dimensional systems. The simulation provides an intriguing classical picture to probe quantum phenomena, namely, a coherent quantum dynamics can be viewed as a globally constrained classical Hamiltonian dynamics of a collection of coupled particles or strings. Efficiency analysis reveals a fundamental difference between the locality in real space and locality in Hilbert space, the latter enables efficient strong analog classical simulations. Examples are also studied to highlight the differences and gaps among various simulation methods. Funding support from NSERC of Canada and a research fellowship at Department of Physics and Astronomy, University of British Columbia are acknowledged

  15. Classical broadcasting is possible with arbitrarily high fidelity and resolution.

    PubMed

    Walker, Thomas A; Braunstein, Samuel L

    2007-02-23

    We quantify the resolution with which any probability distribution may be distinguished from a displaced copy of itself in terms of a characteristic width. This width, which we call the resolution, is well defined for any normalizable probability distribution. We use this concept to study the broadcasting of classical probability distributions. Ideal classical broadcasting creates two (or more) output random variables each of which has the same distribution as the input random variable. We show that the universal broadcasting of probability distributions may be achieved with arbitrarily high fidelities for any finite resolution. By restricting probability distributions to any finite resolution we have therefore shown that the classical limit of quantum broadcasting is consistent with the actual classical case.

  16. Group Testing: Four Student Solutions to a Classic Optimization Problem

    ERIC Educational Resources Information Center

    Teague, Daniel

    2006-01-01

    This article describes several creative solutions developed by calculus and modeling students to the classic optimization problem of testing in groups to find a small number of individuals who test positive in a large population.

  17. Rayleigh-Lagrange formalism for classical dissipative systems.

    PubMed

    Virga, Epifanio G

    2015-01-01

    It is often believed that the Rayleigh-Lagrange formalism for classical dissipative systems is unable to encompass forces described by nonlinear functions of the velocities. Here we show that this is indeed a misconception.

  18. The Popular Classic as a Document in Intellectual History

    ERIC Educational Resources Information Center

    Loader, Colin T.

    1977-01-01

    Describes a university-level course which attempts to make intellectual history more interesting to students through the incorporation of popular classics. The lecture and discussion treatment of 12 literary works is described. (Author/DB)

  19. Classical field isomorphisms in two-fluid plasmas

    SciTech Connect

    Thompson, Richard J.; Moeller, Trevor M.

    2012-08-15

    Previous work recognized a new framework for the equations of a multifluid plasma, wherein each species can be described by a set of equations remarkably similar to the Maxwell equations of classical electrodynamics. This paper extends the previous effort to form an exact isomorphism between the multifluid theory and classical electrodynamics. The major benefits of the new formulation are that the explicit coupling between different species is minimized, and theorems and techniques of classical electrodynamics can be immediately applied to the new multifluid formulation. We introduce the exact isomorphism and investigate some of the immediate consequences from classical electrodynamics. To provide a visualization of the isomorphism, previous 1D and 2D numerical simulations are postprocessed and presented to illustrate the generalized fields and source terms.

  20. Classical chaos and harmonic generation in laser driven nanorings

    NASA Astrophysics Data System (ADS)

    Castiglia, Giuseppe; Corso, Pietro Paolo; Cricchio, Dario; De Giovannini, Umberto; Frusteri, Biagio; Fiordilino, Emilio

    2016-12-01

    A quantum ring driven by an intense laser field emits light in the form of high-harmonic radiation resulting from the strong acceleration experienced by the active electrons forced to move on a curved trajectory. The spectrum of the emitted light is rich and strongly dependent on the parameters of the problem. In order to investigate the physical origin of such variability, we focus on the seemingly simple problem of a laser-driven charge constrained to a ring from a classical standpoint. As it turns out, the dynamics of such a classical electron is governed by a nonlinear equation which results into a chaotic motion—by nature depending on the initial conditions in an unpredictable way. Our results indicate that the quantum harmonic spectra are reminiscent of the classical counterpart and suggest the existence of a line connecting the quantum and classical realms.

    1. Hamilton's Principle and Approximate Solutions to Problems in Classical Mechanics

      ERIC Educational Resources Information Center

      Schlitt, D. W.

      1977-01-01

      Shows how to use the Ritz method for obtaining approximate solutions to problems expressed in variational form directly from the variational equation. Application of this method to classical mechanics is given. (MLH)

    2. A Computer-based Course in Classical Mechanics.

      ERIC Educational Resources Information Center

      Kane, D.; Sherwood, B.

      1980-01-01

      Describes and illustrates the tutorial and homework exercise lessons, student routing, course organization, administration, and evaluation of a PLATO computer-based course in classical mechanics. An appendix lists 41 lessons developed for the course. (CMV)

    3. Variational principles for multisymplectic second-order classical field theories

      NASA Astrophysics Data System (ADS)

      Prieto-Martínez, Pedro Daniel; Román-Roy, Narciso

      2015-06-01

      We state a unified geometrical version of the variational principles for second-order classical field theories. The standard Lagrangian and Hamiltonian variational principles and the corresponding field equations are recovered from this unified framework.

    4. Classical Aspect of the Anomalous Magnetic Moment of the Electron

      NASA Astrophysics Data System (ADS)

      Bordovitsyn, V. A.; Kulikova, A. V.; Savitskaya, Yu. N.

      2017-03-01

      Some integral effects of electromagnetic interactions, such as the electromagnetic mass and the anomalous magnetic moment of the electron, are discussed on the basis of covariant methods of classical electrodynamics.

    5. Mercury Beating Heart: Modifications to the Classical Demonstration

      ERIC Educational Resources Information Center

      Najdoski, Metodija; Mirceski, Valentin; Petrusevski, Vladimir M.; Demiri, Sani

      2007-01-01

      The mercury beating heart (MBH) is a commonly performed experiment, which is based on varying oxidizing agents and substituting other metals for iron. Various modified versions of the classical demonstration of the experiment are presented.

    6. Goblins, Morlocks, and Weasels: Classic Fantasy and the Industrial Revolution.

      ERIC Educational Resources Information Center

      Zanger, Jules

      1977-01-01

      Examines three fantasy classics written at the time of the Industrial Revolution to illustrate the effects of drastic social change on fantasy writing; suggests the possible impact of these fantasies on their readers. (GT)

    7. An Approach to Bridging Classical and Modern Drama

      ERIC Educational Resources Information Center

      Levitt, Paul M.

      1973-01-01

      Employing Oedipus Rex'' and The Birthday Party'' as examples, the author demonstrates that literary criticism should give careful attention to parallels in format and content in the study of classical and modern drama. (RB)

    8. The frenectomy: a comparison of classic versus laser technique.

      PubMed

      Epstein, S R

      1991-08-01

      When an abnormal labial frenum causes certain complications, frenectomy should be considered. In this article, the indications for frenectomy are outlined, classical and laser frenectomy techniques are described, and the advantages and disadvantages of both techniques are discussed.

    9. Making Classical Conditioning Understandable through a Demonstration Technique.

      ERIC Educational Resources Information Center

      Gibb, Gerald D.

      1983-01-01

      One lemon, an assortment of other fruits and vegetables, a tennis ball, and a Galvanic Skin Response meter are needed to implement this approach to teaching about classical conditioning in introductory psychology courses. (RM)

    10. Quantum theory of an electromagnetic observer: Classically behaving macroscopic systems and the emergence of the classical world in quantum electrodynamics

      NASA Astrophysics Data System (ADS)

      Plimak, L. I.; Ivanov, Misha; Aiello, A.; Stenholm, S.

      2015-08-01

      Quantum electrodynamics under conditions of distinguishability of interacting matter entities, and of controlled actions and back-actions between them, is considered. Such "mesoscopic quantum electrodynamics" is shown to share its dynamical structure with the classical stochastic electrodynamics. In formal terms, we demonstrate that all general relations of the mesoscopic quantum electrodynamics may be recast in a form lacking Planck's constant. Mesoscopic quantum electrodynamics is therefore subject to "doing quantum electrodynamics while thinking classically," allowing one to substitute essentially classical considerations for quantum ones without any loss in generality. Implications of these results for the quantum measurement theory are discussed.

    11. Semi-Classical Dirac Vacuum Polarisation in a Scalar Field

      NASA Astrophysics Data System (ADS)

      Lampart, Jonas; Lewin, Mathieu

      2016-08-01

      We study vacuum polarisation effects of a Dirac field coupled to an external scalar field and derive a semi-classical expansion of the regu-larised vacuum energy. The leading order of this expansion is given by a classical formula due to Chin, Lee-Wick and Walecka, for which our result provides the first rigorous proof. We then discuss applications to the non-relativistic large-coupling limit of an interacting system, and to the stability of homogeneous systems.

    12. Generating shortcuts to adiabaticity in quantum and classical dynamics

      NASA Astrophysics Data System (ADS)

      Jarzynski, Christopher

      2013-10-01

      Transitionless quantum driving achieves adiabatic evolution in a hurry, using a counterdiabatic Hamiltonian to stifle nonadiabatic transitions. Here this shortcut to adiabaticity is cast in terms of a generator of adiabatic transport. This yields a classical analog of transitionless driving, and provides a strategy for constructing quantal counterdiabatic Hamiltonians. As an application of this framework, exact classical and quantal counterdiabatic terms are obtained for a particle in a box and for even-power-law potentials in one degree of freedom.

    13. How To Enjoy the Classics. Power of the Printed Word.

      ERIC Educational Resources Information Center

      Allen, Steve

      A classic is a book that gives the exhilarating feeling that a part of life finally has been uncovered. It is a book that has stood the test of time, that people keep reaching for throughout the ages for its special enlightenment. Here are some suggestions to help open up the world of the classics: (1) know if what is being read is a novel, a…

    14. Unbiased estimators for spatial distribution functions of classical fluids.

      PubMed

      Adib, Artur B; Jarzynski, Christopher

      2005-01-01

      We use a statistical-mechanical identity closely related to the familiar virial theorem, to derive unbiased estimators for spatial distribution functions of classical fluids. In particular, we obtain estimators for both the fluid density rho(r) in the vicinity of a fixed solute and the pair correlation g(r) of a homogeneous classical fluid. We illustrate the utility of our estimators with numerical examples, which reveal advantages over traditional histogram-based methods of computing such distributions.

    15. Efficient classical simulation of optical quantum information circuits.

      PubMed

      Bartlett, Stephen D; Sanders, Barry C

      2002-11-11

      We identify a broad class of physical processes in an optical quantum circuit that can be efficiently simulated on a classical computer: this class includes unitary transformations, amplification, noise, and measurements. This simulatability result places powerful constraints on the capability to realize exponential quantum speedups as well as on inducing an optical nonlinear transformation via linear optics, photodetection-based measurement, and classical feedforward of measurement results, optimal cloning, and a wide range of other processes.

    16. Coarsening Measurement References and the Quantum-to-Classical Transition

      NASA Astrophysics Data System (ADS)

      Jeong, Hyunseok; Lim, Youngrong; Kim, M. S.

      2014-01-01

      We investigate the role of inefficiency in quantum measurements in the quantum-to-classical transition, and consistently observe the quantum-to-classical transition by coarsening the references of the measurements (e.g., when and where to measure). Our result suggests that the definition of measurement precision in quantum theory should include the degree of the observer's ability to precisely control the measurement references.

    17. Emergence of a classical Universe from quantum gravity and cosmology.

      PubMed

      Kiefer, Claus

      2012-09-28

      I describe how we can understand the classical appearance of our world from a universal quantum theory. The essential ingredient is the process of decoherence. I start with a general discussion in ordinary quantum theory and then turn to quantum gravity and quantum cosmology. There is a whole hierarchy of classicality from the global gravitational field to the fluctuations in the cosmic microwave background, which serve as the seeds for the structure in the Universe.

    18. The Classical Scattering of Waves: Some Analogies with Quantum Scattering

      DTIC Science & Technology

      1992-01-01

      Code . Approved for public release; distribution is unlimited. 13. Abstract (Maximum 200 words). The scattering of waves in classical physics and quantum...both areas. 92-235222’ 14. Subject Terms. IS. Number of Page. Acoustic scattering , shallow water, waveguide propagation . 27 16. Price Code . 17. Security...Numbers. The Classical Scattering of Waves: Some Analogies with Quantum Scattering Contract ,~~ ~ -V ,~Pom Element NO- 0601153N 6. Author(s). t

    19. Genuine quantum and classical correlations in multipartite systems.

      PubMed

      Giorgi, Gian Luca; Bellomo, Bruno; Galve, Fernando; Zambrini, Roberta

      2011-11-04

      Generalizing the quantifiers used to classify correlations in bipartite systems, we define genuine total, quantum, and classical correlations in multipartite systems. The measure we give is based on the use of relative entropy to quantify the distance between two density matrices. Moreover, we show that, for pure states of three qubits, both quantum and classical bipartite correlations obey a ladder ordering law fixed by two-body mutual informations, or, equivalently, by one-qubit entropies.

    20. Entropies and correlations in classical and quantum systems

      NASA Astrophysics Data System (ADS)

      Man'ko, Margarita A.; Man'ko, Vladimir I.; Marmo, Giuseppe

      2016-09-01

      We present a review of entropy properties for classical and quantum systems including Shannon entropy, von Neumann entropy, Rényi entropy, and Tsallis entropy. We discuss known and new entropic and information inequalities for classical and quantum systems, both composite and noncomposite. We demonstrate matrix inequalities associated with the entropic subadditivity and strong subadditivity conditions and give a new inequality for matrix elements of unitary matrices.

    1. Clinical exuberance of classic Kaposi's sarcoma and response to radiotherapy.

      PubMed

      Trujillo, Jeniffer Muñoz; Alves, Natália Ribeiro de Magalhães; Medeiros, Paula Mota; Azulay-Abulafia, Luna; Alves, Maria de Fátima Guimarães Scotelaro; Gripp, Alexandre Carlos

      2015-01-01

      Kaposi's sarcoma (KS) is a multicentric vascular neoplasm, with cutaneous and extracutaneous involvement. Different clinical and epidemiological variants have been identified. The classic form is manifested mainly in elderly men with indolent and long-term evolution, with lesions localized primarily in the lower extremities. We present two cases of classic Kaposi's sarcoma (CKS) in two female patients with extensive, exuberant skin involvement and rapid evolution, with good response to radiotherapy.

    2. Foundation plan. San Bernardino Valley Union Junior College, Classics Building. ...

      Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

      Foundation plan. San Bernardino Valley Union Junior College, Classics Building. Also includes sections AA-KK (except DD). Howard E. Jones, Architect, San Bernardino, California. Sheet 1, job no. 312. Scales 1/8 inch to the foot (plan) and 1/2 inch to the foot (sections). February 15, 1927. - San Bernardino Valley College, Classics Building, 701 South Mount Vernon Avenue, San Bernardino, San Bernardino County, CA

    3. Classical to quantum correspondence in dissipative directed transport

      NASA Astrophysics Data System (ADS)

      Carlo, Gabriel G.; Rivas, Alejandro M. F.; Spina, María E.

      2015-11-01

      We compare the quantum and classical properties of the (quantum) isoperiodic stable structures [(Q)ISSs], which organize the parameter space of a paradigmatic dissipative ratchet model, i.e., the dissipative modified kicked rotator. We study the spectral behavior of the corresponding classical Perron-Frobenius operators with thermal noise and the quantum superoperators without it for small ℏeff values. We find a remarkable similarity between the classical and quantum spectra. This finding significantly extends previous results—obtained for the mean currents and asymptotic distributions only—and, on the other hand, unveils a classical to quantum correspondence mechanism where the classical noise is qualitatively different from the quantum one. This is crucial not only for simple attractors but also for chaotic ones, where just analyzing the asymptotic distribution is revealed as insufficient. Moreover, we provide with a detailed characterization of relevant eigenvectors by means of the corresponding Weyl-Wigner distributions, in order to better identify similarities and differences. Finally, this model being generic, it allows us to conjecture that this classical to quantum correspondence mechanism is a universal feature of dissipative systems.

    4. Trotter-based simulation of quantum-classical dynamics.

      PubMed

      Kernan, Dónal Mac; Ciccotti, Giovanni; Kapral, Raymond

      2008-01-17

      Quantum rate processes in condensed phase systems are often computed by combining quantum and classical descriptions of the dynamics. An algorithm for simulating the quantum-classical Liouville equation, which describes the dynamics of a quantum subsystem coupled to a classical bath, is presented in this paper. The algorithm is based on a Trotter decomposition of the quantum-classical propagator, in conjunction with Monte Carlo sampling of quantum transitions, to yield a surface-hopping representation of the dynamics. An expression for the nonadiabatic propagator that is responsible for quantum transitions and associated bath momentum changes is derived in a form that is convenient for Monte Carlo sampling and exactly conserves the total energy of the system in individual trajectories. The expectation values of operators or quantum correlation functions can be evaluated by initial sampling of quantum states and use of quantum-classical Liouville dynamics for the time evolution. The algorithm is tested by calculations on the spin-boson model, for which exact quantum results are available, and is shown to reproduce the exact results for stronger nonadiabatic coupling and much longer times using fewer trajectories than other schemes for simulating quantum-classical Liouville dynamics.

    5. Classical-field model of the hydrogen atom

      NASA Astrophysics Data System (ADS)

      Rashkovskiy, Sergey A.

      2017-02-01

      It is shown that all of the basic properties of the hydrogen atom can be consistently described in terms of classical electrodynamics if instead of considering the electron to be a particle, we consider an electrically charged classical wave field—an "electron wave"—which is held by the electrostatic field of the proton. It is shown that quantum mechanics must be considered not as a theory of particles but as a classical field theory in the spirit of classical electrodynamics. In this case, we are not faced with difficulties in interpreting the results of the theory. In the framework of classical electrodynamics, all of the well-known regularities of the spontaneous emission of the hydrogen atom are obtained, which is usually derived in the framework of quantum electrodynamics. It is shown that there are no discrete states and discrete energy levels of the atom: the energy of the atom and its states change continuously. An explanation of the conventional corpuscular-statistical interpretation of atomic phenomena is given. It is shown that this explanation is only a misinterpretation of continuous deterministic processes. In the framework of classical electrodynamics, the nonlinear Schrödinger equation is obtained, which accounts for the inverse action of self-electromagnetic radiation of the electron wave and completely describes the spontaneous emissions of an atom.

    6. Topology of classical molecular optimal control landscapes in phase space

      NASA Astrophysics Data System (ADS)

      Joe-Wong, Carlee; Ho, Tak-San; Long, Ruixing; Rabitz, Herschel; Wu, Rebing

      2013-03-01

      Optimal control of molecular dynamics is commonly expressed from a quantum mechanical perspective. However, in most contexts the preponderance of molecular dynamics studies utilize classical mechanical models. This paper treats laser-driven optimal control of molecular dynamics in a classical framework. We consider the objective of steering a molecular system from an initial point in phase space to a target point, subject to the dynamic constraint of Hamilton's equations. The classical control landscape corresponding to this objective is a functional of the control field, and the topology of the landscape is analyzed through its gradient and Hessian with respect to the control. Under specific assumptions on the regularity of the control fields, the classical control landscape is found to be free of traps that could hinder reaching the objective. The Hessian associated with an optimal control field is shown to have finite rank, indicating the presence of an inherent degree of robustness to control noise. Extensive numerical simulations are performed to illustrate the theoretical principles on (a) a model diatomic molecule, (b) two coupled Morse oscillators, and (c) a chaotic system with a coupled quartic oscillator, confirming the absence of traps in the classical control landscape. We compare the classical formulation with the mathematically analogous quantum state-to-state transition probability control landscape.

    7. Low prevalence of classical galactosemia in Korean population.

      PubMed

      Lee, Beom Hee; Cheon, Chong Kun; Kim, Jae-Min; Kang, Minji; Kim, Joo Hyun; Yang, Song Hyun; Kim, Gu-Hwan; Choi, Jin-Ho; Yoo, Han-Wook

      2011-01-01

      This study described the clinical and molecular genetic features of classical galactosemia in Korean population to contribute to the insight in the spectrum of galactosemia in the world, as little is known about the spectrum and incidence of galactosemia in Asia. During the 11-year study period, only three Korean children were identified as having classical galactosemia on the basis of the enzymatic and molecular genetic analysis. Asians have been reported to have mutations distinct from those of Caucasians and African Americans, indicating that galactose-1-phosphate uridyltransferase mutations are ethnically diverse. Our three patients had a total of three mutations (c.252+1G > A, p.Q169H and p.E363K), two of which were novel (p.E363K and c.252+1G > A) mutations. Interestingly, c.252+1G > A, which leads to skipping of exon 2, was observed in all three patients (three of six alleles), indicating that this mutation may be common in Koreans with classical galactosemia. Screening for classical galactosemia in 158,126 Korean newborns identified no patient with classical galactosemia. In conclusion, our findings provide further evidence for the ethnic diversity of classical galactosemia, which may be as rare in Koreans as in other Asian populations.

    8. Classical trajectory models for electronically nonadiabatic collision processes: A classical valence bond model for electronic degrees of freedom

      SciTech Connect

      Miller, William H.; Orel, Ann E.

      1981-06-01

      A classical interpretation of the Dirac–Van Vleck spin version of valence bond theory is used in this research to obtain a classical model for electronic degrees of freedom within the valence bond framework. The approach is illustrated by deriving the explicit forms of the classical Hamiltonians, involving electronic and heavy particle degrees of freedom, for the H–H2, F–H2, and O–H2 systems. It is also shown how the initial conditions for both electronic and heavy particle degrees of freedom are chosen to carry out a classical trajectory simulation of collision processes. In addition, the attractive feature of this model is that it is as easily applicable to electronically nonadiabatic processes as it is to adiabatic ones.

    9. Characterization of Classical and Nonclassical Fabry Disease: A Multicenter Study.

      PubMed

      Arends, Maarten; Wanner, Christoph; Hughes, Derralynn; Mehta, Atul; Oder, Daniel; Watkinson, Oliver T; Elliott, Perry M; Linthorst, Gabor E; Wijburg, Frits A; Biegstraaten, Marieke; Hollak, Carla E

      2016-12-15

      Fabry disease leads to renal, cardiac, and cerebrovascular manifestations. Phenotypic differences between classically and nonclassically affected patients are evident, but there are few data on the natural course of classical and nonclassical disease in men and women. To describe the natural course of Fabry disease stratified by sex and phenotype, we retrospectively assessed event-free survival from birth to the first clinical visit (before enzyme replacement therapy) in 499 adult patients (mean age 43 years old; 41% men; 57% with the classical phenotype) from three international centers of excellence. We classified patients by phenotype on the basis of characteristic symptoms and enzyme activity. Men and women with classical Fabry disease had higher event rate than did those with nonclassical disease (hazard ratio for men, 5.63, 95% confidence interval, 3.17 to 10.00; P<0.001; hazard ratio for women, 2.88, 95% confidence interval, 1.54 to 5.40; P<0.001). Furthermore, men with classical Fabry disease had lower eGFR, higher left ventricular mass, and higher plasma globotriaosylsphingosine concentrations than men with nonclassical Fabry disease or women with either phenotype (P<0.001). In conclusion, before treatment with enzyme replacement therapy, men with classical Fabry disease had a history of more events than men with nonclassical disease or women with either phenotype; women with classical Fabry disease were more likely to develop complications than women with nonclassical disease. These data may support the development of new guidelines for the monitoring and treatment of Fabry disease and studies on the effects of intervention in subgroups of patients.

    10. Classical morphology of plants as an elementary instance of classical invariant theory.

      PubMed

      Mavrodiev, Evgeny V

      2009-09-11

      It has long been known that structural chemistry shows an intriguing correspondence with Classical Invariant Theory (CIT). Under this view, an algebraic binary form of the degree n corresponds to a chemical atom with valence n and each physical molecule or ion has an invariant-theoretic counterpart. This theory was developed using the Aronhold symbolical approach and the symbolical processes of convolution/transvection in CIT was characterized as a potential "accurate morphological method". However, CIT has not been applied to the formal morphology of living organisms. Based on the morphological interpretation of binary form, as well as the process of convolution/transvection, the First and Second Fundamental Theorems of CIT and the Nullforms of CIT, we show how CIT can be applied to the structure of plants, especially when conceptualized as a series of plant metamers (phytomers). We also show that the weight of the covariant/invariant that describes a morphological structure is a criterion of simplicity and, therefore, we argue that this allows us to formulate a parsimonious method of formal morphology. We demonstrate that the "theory of axilar bud" is the simplest treatment of the grass seedling/embryo. Our interpretations also represent Troll's bauplan of the angiosperms, the principle of variable proportions, morphological misfits, the basic types of stem segmentation, and Goethe's principle of metamorphosis in terms of CIT. Binary forms of different degrees might describe any repeated module of plant organisms. As bacteria, invertebrates, and higher vertebrates are all generally shared a metameric morphology, wider implications of the proposed symmetry between CIT and formal morphology of plants are apparent.

    11. Classical and non-classical causes of GH deficiency in the paediatric age.

      PubMed

      Di Iorgi, Natascia; Morana, Giovanni; Allegri, Anna Elsa Maria; Napoli, Flavia; Gastaldi, Roberto; Calcagno, Annalisa; Patti, Giuseppa; Loche, Sandro; Maghnie, Mohamad

      2016-12-01

      Growth hormone deficiency (GHD) may result from a failure of hypothalamic GHRH production or release, from congenital disorders of pituitary development, or from central nervous system insults including tumors, surgery, trauma, radiation or infiltration from inflammatory diseases. Idiopathic, isolated GHD is the most common sporadic form of hypopituitarism. GHD may also occur in combination with other pituitary hormone deficiencies, and is often referred to as hypopituitarism, combined pituitary hormone deficiency (CPHD), multiple pituitary hormone deficiency (MPHD) or panhypopituitarism. Children without any identifiable cause of their GHD are commonly labeled as having idiopathic hypopituitarism. MRI imaging is the technique of choice in the diagnosis of children with hypopituitarism. Marked differences in MRI pituitary gland morphology suggest different etiologies of GHD and different prognoses. Pituitary stalk agenesis and ectopic posterior pituitary (EPP) are specific markers of permanent GHD, and patients with these MRI findings show a different clinical and endocrine outcome compared to those with normal pituitary anatomy or hypoplastic pituitary alone. Furthermore, the classic triad of ectopic posterior pituitary gland, pituitary stalk hypoplasia/agenesis, and anterior pituitary gland hypoplasia is generally associated with permanent GHD. T2 DRIVE images aid in the identification of pituitary stalk without the use of contrast medium administration. Future developments in imaging techniques will undoubtedly reveal additional insights. Mutations in a number of genes encoding transcription factors - such as HESX1, SOX2, SOX3, LHX3, LHX4, PROP1, POU1F1, PITX, GLI3, GLI2, OTX2, ARNT2, IGSF1, FGF8, FGFR1, PROKR2, PROK2, CHD7, WDR11, NFKB2, PAX6, TCF7L1, IFT72, GPR161 and CDON - have been associated with pituitary dysfunction and abnormal pituitary gland development; the correlation of genetic mutations to endocrine and MRI phenotypes has improved our knowledge of

    12. Playing with functions of positive type, classical and quantum

      NASA Astrophysics Data System (ADS)

      Aniello, Paolo

      2015-06-01

      A function of positive type can be defined as a positive functional on a convolution algebra of a locally compact group. In the case where the group is abelian, by Bochner’s theorem a function of positive type is, up to normalization, the Fourier transform of a probability measure. Therefore, considering the group of translations on phase space, a suitably normalized phase-space function of positive type can be regarded as a realization of a classical state. Thus, it may be called a function of classical positive type. Replacing the ordinary convolution on phase space with the twisted convolution, one obtains a noncommutative algebra of functions whose positive functionals we may call functions of quantum positive type. In fact, by a quantum version of Bochner’s theorem, a continuous function of quantum positive type is, up to normalization, the (symplectic) Fourier transform of a Wigner quasi-probability distribution; hence, it can be regarded as a phase-space realization of a quantum state. Playing with functions of positive type—classical and quantum—one is led in a natural way to consider a class of semigroups of operators, the classical-quantum semigroups. The physical meaning of these mathematical objects is unveiled via quantization, so obtaining a class of quantum dynamical semigroups that, borrowing terminology from quantum information science, may be called classical-noise semigroups.

    13. Escaping the crunch: Gravitational effects in classical transitions

      NASA Astrophysics Data System (ADS)

      Johnson, Matthew C.; Yang, I.-Sheng

      2010-09-01

      During eternal inflation, a landscape of vacua can be populated by the nucleation of bubbles. These bubbles inevitably collide, and collisions sometimes displace the field into a new minimum in a process known as a classical transition. In this paper, we examine some new features of classical transitions that arise when gravitational effects are included. Using the junction condition formalism, we study the conditions for energy conservation in detail, and solve explicitly for the types of allowed classical transition geometries. We show that the repulsive nature of domain walls, and the de Sitter expansion associated with a positive energy minimum, can allow for classical transitions to vacua of higher energy than that of the colliding bubbles. Transitions can be made out of negative or zero energy (terminal) vacua to a de Sitter phase, restarting eternal inflation, and populating new vacua. However, the classical transition cannot produce vacua with energy higher than the original parent vacuum, which agrees with previous results on the construction of pockets of false vacuum. We briefly comment on the possible implications of these results for various measure proposals in eternal inflation.

    14. Is classical flat Kasner spacetime flat in quantum gravity?

      NASA Astrophysics Data System (ADS)

      Singh, Parampreet

      2016-05-01

      Quantum nature of classical flat Kasner spacetime is studied using effective spacetime description in loop quantum cosmology (LQC). We find that even though the spacetime curvature vanishes at the classical level, nontrivial quantum gravitational effects can arise. For the standard loop quantization of Bianchi-I spacetime, which uniquely yields universal bounds on expansion and shear scalars and results in a generic resolution of strong singularities, we find that a flat Kasner metric is not a physical solution of the effective spacetime description, except in a limit. The lack of a flat Kasner metric at the quantum level results from a novel feature of the loop quantum Bianchi-I spacetime: quantum geometry induces nonvanishing spacetime curvature components, making it not Ricci flat even when no matter is present. The noncurvature singularity of the classical flat Kasner spacetime is avoided, and the effective spacetime transits from a flat Kasner spacetime in asymptotic future, to a Minkowski spacetime in asymptotic past. Interestingly, for an alternate loop quantization which does not share some of the fine features of the standard quantization, flat Kasner spacetime with expected classical features exists. In this case, even with nontrivial quantum geometric effects, the spacetime curvature vanishes. These examples show that the character of even a flat classical vacuum spacetime can alter in a fundamental way in quantum gravity and is sensitive to the quantization procedure.

    15. Simultaneous classical communication and quantum key distribution using continuous variables

      DOE PAGES

      Qi, Bing

      2016-10-26

      Currently, classical optical communication systems employing strong laser pulses and quantum key distribution (QKD) systems working at single-photon levels are very different communication modalities. Dedicated devices are commonly required to implement QKD. In this paper, we propose a scheme which allows classical communication and QKD to be implemented simultaneously using the same communication infrastructure. More specially, we propose a coherent communication scheme where both the bits for classical communication and the Gaussian distributed random numbers for QKD are encoded on the same weak coherent pulse and decoded by the same coherent receiver. Simulation results based on practical system parameters showmore » that both deterministic classical communication with a bit error rate of 10–9 and secure key distribution could be achieved over tens of kilometers of single-mode fibers. It is conceivable that in the future coherent optical communication network, QKD will be operated in the background of classical communication at a minimal cost.« less

    16. Classical and quantum cosmology of minimal massive bigravity

      NASA Astrophysics Data System (ADS)

      Darabi, F.; Mousavi, M.

      2016-10-01

      In a Friedmann-Robertson-Walker (FRW) space-time background we study the classical cosmological models in the context of recently proposed theory of nonlinear minimal massive bigravity. We show that in the presence of perfect fluid the classical field equations acquire contribution from the massive graviton as a cosmological term which is positive or negative depending on the dynamical competition between two scale factors of bigravity metrics. We obtain the classical field equations for flat and open universes in the ordinary and Schutz representation of perfect fluid. Focusing on the Schutz representation for flat universe, we find classical solutions exhibiting singularities at early universe with vacuum equation of state. Then, in the Schutz representation, we study the quantum cosmology for flat universe and derive the Schrodinger-Wheeler-DeWitt equation. We find its exact and wave packet solutions and discuss on their properties to show that the initial singularity in the classical solutions can be avoided by quantum cosmology. Similar to the study of Hartle-Hawking no-boundary proposal in the quantum cosmology of de Rham, Gabadadze and Tolley (dRGT) massive gravity, it turns out that the mass of graviton predicted by quantum cosmology of the minimal massive bigravity is large at early universe. This is in agreement with the fact that at early universe the cosmological constant should be large.

    17. Mouse Spermatogenesis Requires Classical and Nonclassical Testosterone Signaling.

      PubMed

      Toocheck, Corey; Clister, Terri; Shupe, John; Crum, Chelsea; Ravindranathan, Preethi; Lee, Tae-Kyung; Ahn, Jung-Mo; Raj, Ganesh V; Sukhwani, Meena; Orwig, Kyle E; Walker, William H

      2016-01-01

      Testosterone acts though the androgen receptor in Sertoli cells to support germ cell development (spermatogenesis) and male fertility, but the molecular and cellular mechanisms by which testosterone acts are not well understood. Previously, we found that in addition to acting through androgen receptor to directly regulate gene expression (classical testosterone signaling pathway), testosterone acts through a nonclassical pathway via the androgen receptor to rapidly activate kinases that are known to regulate spermatogenesis. In this study, we provide the first evidence that nonclassical testosterone signaling occurs in vivo as the MAP kinase cascade is rapidly activated in Sertoli cells within the testis by increasing testosterone levels in the rat. We find that either classical or nonclassical signaling regulates testosterone-mediated Rhox5 gene expression in Sertoli cells within testis explants. The selective activation of classical or nonclassical signaling pathways in Sertoli cells within testis explants also resulted in the differential activation of the Zbtb16 and c-Kit genes in adjacent spermatogonia germ cells. Delivery of an inhibitor of either pathway to Sertoli cells of mouse testes disrupted the blood-testis barrier that is essential for spermatogenesis. Furthermore, an inhibitor of nonclassical testosterone signaling blocked meiosis in pubertal mice and caused the loss of meiotic and postmeiotic germ cells in adult mouse testes. An inhibitor of the classical pathway caused the premature release of immature germ cells. Collectively, these observations indicate that classical and nonclassical testosterone signaling regulate overlapping and distinct functions that are required for the maintenance of spermatogenesis and male fertility.

    18. Classical and quantum mechanics of diatomic molecules in tilted fields.

      PubMed

      Arango, Carlos A; Kennerly, William W; Ezra, Gregory S

      2005-05-08

      We investigate the classical and quantum mechanics of diatomic molecules in noncollinear (tilted) static electric and nonresonant linearly polarized laser fields. The classical diatomic in tilted fields is a nonintegrable system, and we study the phase space structure for physically relevant parameter regimes for the molecule KCl. While exhibiting low-energy (pendular) and high-energy (free-rotor) integrable limits, the rotor in tilted fields shows chaotic dynamics at intermediate energies, and the degree of classical chaos can be tuned by changing the tilt angle. We examine the quantum mechanics of rotors in tilted fields. Energy-level correlation diagrams are computed, and the presence of avoided crossings quantified by the study of nearest-neighbor spacing distributions as a function of energy and tilting angle. Finally, we examine the influence of classical periodic orbits on rotor wave functions. Many wave functions in the tilted field case are found to be highly nonseparable in spherical polar coordinates. Localization of wave functions in the vicinity of classical periodic orbits, both stable and unstable, is observed for many states.

    19. On the co-creation of classical and modern physics.

      PubMed

      Staley, Richard

      2005-12-01

      While the concept of "classical physics" has long framed our understanding of the environment from which modern physics emerged, it has consistently been read back into a period in which the physicists concerned initially considered their work in quite other terms. This essay explores the shifting currency of the rich cultural image of the classical/ modern divide by tracing empirically different uses of "classical" within the physics community from the 1890s to 1911. A study of fin-de-siècle addresses shows that the earliest general uses of the concept proved controversial. Our present understanding of the term was in large part shaped by its incorporation (in different ways) within the emerging theories of relativity and quantum theory--where the content of "classical" physics was defined by proponents of the new. Studying the diverse ways in which Boltzmann, Larmor, Poincaré, Einstein, Minkowski, and Planck invoked the term "classical" will help clarify the critical relations between physicists' research programs and their use of worldview arguments in fashioning modern physics.

    20. Lymphangiogenesis in Classical Hodgkin Lymphoma - Preliminary Study with Clinicopathological Correlations

      PubMed Central

      Benharroch, Daniel; Prinsloo, Isebrand; Gopas, Jacob; Lazarev, Irena

      2016-01-01

      A role for lymphangiogenesis in metastatic breast and prostate cancers has been suggested recently. The relevance of lymphangiogenesis in cancer as a rule, and more specifically in classical Hodgkin lymphoma, is poorly understood in comparison with that of angiogenesis. In a preliminary (pilot) study we have investigated the role of lymphatic vessels growth in 19 cases of classical Hodgkin lymphoma stained with the D2-40 (podoplanin) antibody. In each case, three lymphatic vessels hot spots were scrutinized twice. Of the 57 hot spots thus identified, we chose 15 at random for photography, microvessel counting and image analysis. We determined the mean perimeter, surface area, major axis length and complexity factor for each hot spot and correlated them with clinical and biological features of classical Hodgkin lymphoma. No correlations were found with clinical features. No associations were noted with the standard immuno-markers of classical Hodgkin lymphoma. However, significant inverse correlations were shown with pRb, BAX and IκB-α expression. The mean lymphatic major axis length was inversely correlated with the complexity factor. Last, we carried out an additional clinicopathological correlation of the expression of pRb, BAX and IκB-α in a cohort of classical Hodgkin lymphoma patients previously published. PMID:27877228

    1. SPRED: A machine learning approach for the identification of classical and non-classical secretory proteins in mammalian genomes

      SciTech Connect

      Kandaswamy, Krishna Kumar; Pugalenthi, Ganesan; Hartmann, Enno; Kalies, Kai-Uwe; Moeller, Steffen; Suganthan, P.N.; Martinetz, Thomas

      2010-01-15

      Eukaryotic protein secretion generally occurs via the classical secretory pathway that traverses the ER and Golgi apparatus. Secreted proteins usually contain a signal sequence with all the essential information required to target them for secretion. However, some proteins like fibroblast growth factors (FGF-1, FGF-2), interleukins (IL-1 alpha, IL-1 beta), galectins and thioredoxin are exported by an alternative pathway. This is known as leaderless or non-classical secretion and works without a signal sequence. Most computational methods for the identification of secretory proteins use the signal peptide as indicator and are therefore not able to identify substrates of non-classical secretion. In this work, we report a random forest method, SPRED, to identify secretory proteins from protein sequences irrespective of N-terminal signal peptides, thus allowing also correct classification of non-classical secretory proteins. Training was performed on a dataset containing 600 extracellular proteins and 600 cytoplasmic and/or nuclear proteins. The algorithm was tested on 180 extracellular proteins and 1380 cytoplasmic and/or nuclear proteins. We obtained 85.92% accuracy from training and 82.18% accuracy from testing. Since SPRED does not use N-terminal signals, it can detect non-classical secreted proteins by filtering those secreted proteins with an N-terminal signal by using SignalP. SPRED predicted 15 out of 19 experimentally verified non-classical secretory proteins. By scanning the entire human proteome we identified 566 protein sequences potentially undergoing non-classical secretion. The dataset and standalone version of the SPRED software is available at (http://www.inb.uni-luebeck.de/tools-demos/spred/spred).

    2. The ambiguity of simplicity in quantum and classical simulation

      NASA Astrophysics Data System (ADS)

      Aghamohammadi, Cina; Mahoney, John R.; Crutchfield, James P.

      2017-04-01

      A system's perceived simplicity depends on whether it is represented classically or quantally. This is not so surprising, as classical and quantum physics are descriptive frameworks built on different assumptions that capture, emphasize, and express different properties and mechanisms. What is surprising is that, as we demonstrate, simplicity is ambiguous: the relative simplicity between two systems can change sign when moving between classical and quantum descriptions. Here, we associate simplicity with small model-memory. We see that the notions of absolute physical simplicity at best form a partial, not a total, order. This suggests that appeals to principles of physical simplicity, via Ockham's Razor or to the ;elegance; of competing theories, may be fundamentally subjective. Recent rapid progress in quantum computation and quantum simulation suggest that the ambiguity of simplicity will strongly impact statistical inference and, in particular, model selection.

    3. Quantum nonlocality and the end of classical spacetime

      NASA Astrophysics Data System (ADS)

      Banerjee, Shreya; Bera, Sayantani; Singh, Tejinder P.

      2016-07-01

      Quantum nonlocal correlations and the acausal, spooky action at a distance suggest a discord between quantum theory and special relativity. We propose a resolution for this discord by first observing that there is a problem of time in quantum theory. There should exist a reformulation of quantum theory which does not refer to classical time. Such a reformulation is obtained by suggesting that spacetime is fundamentally noncommutative. Quantum theory without classical time is the equilibrium statistical thermodynamics of the underlying noncommutative relativity. Stochastic fluctuations about equilibrium give rise to the classical limit and ordinary spacetime geometry. However, measurement on an entangled state can be correctly described only in the underlying noncommutative spacetime, where there is no causality violation, nor a spooky action at a distance.

    4. Implications of purely classical gravity for inflationary tensor modes

      NASA Astrophysics Data System (ADS)

      Ashoorioon, Amjad; Dev, P. S. Bhupal; Mazumdar, Anupam

      2014-09-01

      We discuss the implications of a purely classical (instead of quantum) theory of gravity for the primordial gravitational wave spectrum generated during inflation. We argue that for a scalar field driven inflation in a classical gravity the amplitude of the gravitational wave will be too small, irrespective of its primordial seed, to be detected in any forthcoming experiments. Therefore, a positive detection of the B-mode polarizations in the Cosmic Microwave Background (CMB) spectrum will naturally confirm the quantum nature of gravity itself. Furthermore there will be no upper limit on the scale of inflation in the case of classical gravity, and a high-scale model of inflation can easily bypass the observational constraints.

    5. The Classic/climb Beam Combiner at the CHARA Array

      NASA Astrophysics Data System (ADS)

      Ten Brummelaar, T. A.; Sturmann, J.; Ridgway, S. T.; Sturmann, L.; Turner, N. H.; McAlister, H. A.; Farrington, C. D.; Beckmann, U.; Weigelt, G.; Shure, M.

      In the same way that every telescope has multiple instruments and cameras, an interferometric array like the CHARA Array will have numerous beam combiners at the back end. And like the instruments of a single telescope, each of these combiners will be optimized for a particular kind of observation or scientific program. In this paper we describe the CLASSIC and CLIMB beam combiners of the CHARA Array. Both are open air, aperture plane, wide bandwidth single spectral channel instruments optimized for sensitivity. CLASSIC is the original two beam combiner used for the first science at CHARA, and it still has the faintest magnitude limit. CLIMB is a three beam expansion of CLASSIC that can also provide closure phase measurements.

    6. Integral approximations to classical diffusion and smoothed particle hydrodynamics

      SciTech Connect

      Du, Qiang; Lehoucq, R. B.; Tartakovsky, A. M.

      2014-12-31

      The contribution of the paper is the approximation of a classical diffusion operator by an integral equation with a volume constraint. A particular focus is on classical diffusion problems associated with Neumann boundary conditions. By exploiting this approximation, we can also approximate other quantities such as the flux out of a domain. Our analysis of the model equation on the continuum level is closely related to the recent work on nonlocal diffusion and peridynamic mechanics. In particular, we elucidate the role of a volumetric constraint as an approximation to a classical Neumann boundary condition in the presence of physical boundary. The volume-constrained integral equation then provides the basis for accurate and robust discretization methods. As a result, an immediate application is to the understanding and improvement of the Smoothed Particle Hydrodynamics (SPH) method.

    7. Investigation of classical radiation reaction with aligned crystals

      NASA Astrophysics Data System (ADS)

      Di Piazza, A.; Wistisen, Tobias N.; Uggerhøj, Ulrik I.

      2017-02-01

      Classical radiation reaction is the effect of the electromagnetic field emitted by an accelerated electric charge on the motion of the charge itself. The self-consistent underlying classical equation of motion including radiation-reaction effects, the Landau-Lifshitz equation, has never been tested experimentally, in spite of the first theoretical treatments of radiation reaction having been developed more than a century ago. Here we show that classical radiation reaction effects, in particular those due to the near electromagnetic field, as predicted by the Landau-Lifshitz equation, can be measured in principle using presently available facilities, in the energy emission spectrum of 30-GeV electrons crossing a 0.55-mm thick diamond crystal in the axial channeling regime. Our theoretical results indicate the feasibility of the suggested setup, e.g., at the CERN Secondary Beam Areas (SBA) beamlines.

    8. Properties of the Boltzmann equation in the classical approximation

      DOE PAGES

      Epelbaum, Thomas; Gelis, François; Tanji, Naoto; ...

      2014-12-30

      We examine the Boltzmann equation with elastic point-like scalar interactions in two different versions of the the classical approximation. Although solving numerically the Boltzmann equation with the unapproximated collision term poses no problem, this allows one to study the effect of the ultraviolet cutoff in these approximations. This cutoff dependence in the classical approximations of the Boltzmann equation is closely related to the non-renormalizability of the classical statistical approximation of the underlying quantum field theory. The kinetic theory setup that we consider here allows one to study in a much simpler way the dependence on the ultraviolet cutoff, since onemore » has also access to the non-approximated result for comparison.« less

    9. Integrability of classical strings dual for noncommutative gauge theories

      NASA Astrophysics Data System (ADS)

      Matsumoto, Takuya; Yoshida, Kentaroh

      2014-06-01

      We derive the gravity duals of noncommutative gauge theories from the Yang-Baxter sigma model description of the AdS5 × S5 superstring with classical r-matrices. The corresponding classical r-matrices are 1) solutions of the classical Yang-Baxter equation (CYBE), 2) skew-symmetric, 3) nilpotent and 4) abelian. Hence these should be called abelian Jordanian deformations. As a result, the gravity duals are shown to be integrable deformations of AdS5 × S5. Then, abelian twists of AdS5 are also investigated. These results provide a support for the gravity/CYBE correspondence proposed in arXiv:1404.1838.

    10. Integral approximations to classical diffusion and smoothed particle hydrodynamics

      DOE PAGES

      Du, Qiang; Lehoucq, R. B.; Tartakovsky, A. M.

      2014-12-31

      The contribution of the paper is the approximation of a classical diffusion operator by an integral equation with a volume constraint. A particular focus is on classical diffusion problems associated with Neumann boundary conditions. By exploiting this approximation, we can also approximate other quantities such as the flux out of a domain. Our analysis of the model equation on the continuum level is closely related to the recent work on nonlocal diffusion and peridynamic mechanics. In particular, we elucidate the role of a volumetric constraint as an approximation to a classical Neumann boundary condition in the presence of physical boundary.more » The volume-constrained integral equation then provides the basis for accurate and robust discretization methods. As a result, an immediate application is to the understanding and improvement of the Smoothed Particle Hydrodynamics (SPH) method.« less

    11. Integral approximations to classical diffusion and smoothed particle hydrodynamics

      SciTech Connect

      Du, Q.; Lehoucq, Richard B.; Tartakovsky, Alexandre M.

      2015-04-01

      The contribution of the paper is the approximation of a classical diffusion operator by an integral equation with a volume constraint. A particular focus is on classical diffusion problems associated with Neumann boundary conditions. By exploiting this approximation, we can also approximate other quantities such as the flux out of a domain. Our analysis of the model equation on the continuum level is closely related to the recent work on nonlocal diffusion and peridynamic mechanics. In particular, we elucidate the role of a volumetric constraint as an approximation to a classical Neumann boundary condition in the presence of physical boundary. The volume-constrained integral equation then provides the basis for accurate and robust discretization methods. An immediate application is to the understanding and improvement of the Smoothed Particle Hydrodynamics (SPH) method.

    12. Vaccination influences the evolution of classical swine fever virus.

      PubMed

      Ji, Wei; Niu, Dan-Dan; Si, Hong-Li; Ding, Nai-Zheng; He, Cheng-Qiang

      2014-07-01

      Classical swine fever is a serious, economically damaging disease caused by classical swine fever virus (CSFV). The CSFV is composed of two clades, according to phylogenetic estimates. Attenuated live vaccine such as HCLV, has been widely used to protect pigs from CSFV, but the influence of vaccination on the evolution of CSFV has not been studied. We conducted a systemic analysis of the impact of vaccination on the evolution of CSFV by comparing vaccine-related and non-vaccine-related CSFV groups. We found that vaccination may affect strain diversity and immune escape through recombination and point mutation. We also found that vaccination may influence the population dynamics, evolutionary rate and adaptive evolution of classical swine fever virus. Our evidence suggests that the vaccination might also change host adaptation through influencing codon usage of the virus in swine. These findings suggest that it is necessary to avoid excessive use of CSFV attenuated vaccines.

    13. Classical and quantum dynamics in an inverse square potential

      SciTech Connect

      Guillaumín-España, Elisa; Núñez-Yépez, H. N.; Salas-Brito, A. L.

      2014-10-15

      The classical motion of a particle in a 3D inverse square potential with negative energy, E, is shown to be geodesic, i.e., equivalent to the particle's free motion on a non-compact phase space manifold irrespective of the sign of the coupling constant. We thus establish that all its classical orbits with E < 0 are unbounded. To analyse the corresponding quantum problem, the Schrödinger equation is solved in momentum space. No discrete energy levels exist in the unrenormalized case and the system shows a complete “fall-to-the-center” with an energy spectrum unbounded by below. Such behavior corresponds to the non-existence of bound classical orbits. The symmetry of the problem is SO(3) × SO(2, 1) corroborating previously obtained results.

    14. Properties of the Boltzmann equation in the classical approximation

      SciTech Connect

      Epelbaum, Thomas; Gelis, François; Tanji, Naoto; Wu, Bin

      2014-12-30

      We examine the Boltzmann equation with elastic point-like scalar interactions in two different versions of the the classical approximation. Although solving numerically the Boltzmann equation with the unapproximated collision term poses no problem, this allows one to study the effect of the ultraviolet cutoff in these approximations. This cutoff dependence in the classical approximations of the Boltzmann equation is closely related to the non-renormalizability of the classical statistical approximation of the underlying quantum field theory. The kinetic theory setup that we consider here allows one to study in a much simpler way the dependence on the ultraviolet cutoff, since one has also access to the non-approximated result for comparison.

    15. Plasmon mass scale in classical nonequilibrium gauge theory

      NASA Astrophysics Data System (ADS)

      Lappi, T.; Peuron, J.

      2017-01-01

      Classical lattice Yang-Mills calculations provide a good way to understand different nonequilibrium phenomena in nonperturbatively overoccupied systems. Above the Debye scale the classical theory can be matched smoothly to kinetic theory. The aim of this work is to study the limits of this quasiparticle picture by determining the plasmon mass in classical real-time Yang-Mills theory on a lattice in three spatial dimensions. We compare three methods to determine the plasmon mass: a hard thermal loop expression in terms of the particle distribution, an effective dispersion relation constructed from fields and their time derivatives, and the measurement of oscillations between electric and magnetic field modes after artificially introducing a homogeneous color electric field. We find that a version of the dispersion relation that uses electric fields and their time derivatives agrees with the other methods within 50%.

    16. Classical kinematics for isotropic, minimal Lorentz-violating fermion operators

      NASA Astrophysics Data System (ADS)

      Schreck, M.

      2015-05-01

      In this article a particular classical, relativistic Lagrangian based on the isotropic fermion sector of the Lorentz-violating (minimal) Standard Model extension is considered. The motion of the associated classical particle in an external electromagnetic field is studied, and the evolution of its spin, which is introduced by hand, is investigated. It is shown that the particle travels along trajectories that are scaled versions of the standard ones. Furthermore there is no spin precession due to Lorentz violation, but the rate is modified at which the longitudinal and transverse spin components transform into each other. This demonstrates that it is practical to consider classical physics within such an isotropic Lorentz-violating framework and it opens the pathway to study a curved background in that context.

    17. Quantum mechanics can reduce the complexity of classical models.

      PubMed

      Gu, Mile; Wiesner, Karoline; Rieper, Elisabeth; Vedral, Vlatko

      2012-03-27

      Mathematical models are an essential component of quantitative science. They generate predictions about the future, based on information available in the present. In the spirit of simpler is better; should two models make identical predictions, the one that requires less input is preferred. Yet, for almost all stochastic processes, even the provably optimal classical models waste information. The amount of input information they demand exceeds the amount of predictive information they output. Here we show how to systematically construct quantum models that break this classical bound, and that the system of minimal entropy that simulates such processes must necessarily feature quantum dynamics. This indicates that many observed phenomena could be significantly simpler than classically possible should quantum effects be involved.

    18. Generic emergence of classical features in quantum Darwinism

      NASA Astrophysics Data System (ADS)

      Brandão, Fernando G. S. L.; Piani, Marco; Horodecki, Paweł

      2015-08-01

      Quantum Darwinism posits that only specific information about a quantum system that is redundantly proliferated to many parts of its environment becomes accessible and objective, leading to the emergence of classical reality. However, it is not clear under what conditions this mechanism holds true. Here we prove that the emergence of classical features along the lines of quantum Darwinism is a general feature of any quantum dynamics: observers who acquire information indirectly through the environment have effective access at most to classical information about one and the same measurement of the quantum system. Our analysis does not rely on a strict conceptual splitting between a system-of-interest and its environment, and allows one to interpret any system as part of the environment of any other system. Finally, our approach leads to a full operational characterization of quantum discord in terms of local redistribution of correlations.

    19. Generic emergence of classical features in quantum Darwinism.

      PubMed

      Brandão, Fernando G S L; Piani, Marco; Horodecki, Paweł

      2015-08-12

      Quantum Darwinism posits that only specific information about a quantum system that is redundantly proliferated to many parts of its environment becomes accessible and objective, leading to the emergence of classical reality. However, it is not clear under what conditions this mechanism holds true. Here we prove that the emergence of classical features along the lines of quantum Darwinism is a general feature of any quantum dynamics: observers who acquire information indirectly through the environment have effective access at most to classical information about one and the same measurement of the quantum system. Our analysis does not rely on a strict conceptual splitting between a system-of-interest and its environment, and allows one to interpret any system as part of the environment of any other system. Finally, our approach leads to a full operational characterization of quantum discord in terms of local redistribution of correlations.

    20. Complementarity of information and the emergence of the classical world

      NASA Astrophysics Data System (ADS)

      Zwolak, Michael; Zurek, Wojciech

      2013-03-01

      We prove an anti-symmetry property relating accessible information about a system through some auxiliary system F and the quantum discord with respect to a complementary system F'. In Quantum Darwinism, where fragments of the environment relay information to observers - this relation allows us to understand some fundamental properties regarding correlations between a quantum system and its environment. First, it relies on a natural separation of accessible information and quantum information about a system. Under decoherence, this separation shows that accessible information is maximized for the quasi-classical pointer observable. Other observables are accessible only via correlations with the pointer observable. Second, It shows that objective information becomes accessible to many observers only when quantum information is relegated to correlations with the global environment, and, therefore, locally inaccessible. The resulting complementarity explains why, in a quantum Universe, we perceive objective classical reality, and supports Bohr's intuition that quantum phenomena acquire classical reality only when communicated.

    1. Complementarity of quantum discord and classically accessible information

      SciTech Connect

      Zwolak, Michael P.; Zurek, Wojciech H.

      2013-05-20

      The sum of the Holevo quantity (that bounds the capacity of quantum channels to transmit classical information about an observable) and the quantum discord (a measure of the quantumness of correlations of that observable) yields an observable-independent total given by the quantum mutual information. This split naturally delineates information about quantum systems accessible to observers – information that is redundantly transmitted by the environment – while showing that it is maximized for the quasi-classical pointer observable. Other observables are accessible only via correlations with the pointer observable. In addition, we prove an anti-symmetry property relating accessible information and discord. It shows that information becomes objective – accessible to many observers – only as quantum information is relegated to correlations with the global environment, and, therefore, locally inaccessible. Lastly, the resulting complementarity explains why, in a quantum Universe, we perceive objective classical reality while flagrantly quantum superpositions are out of reach.

    2. Complementarity of quantum discord and classically accessible information

      DOE PAGES

      Zwolak, Michael P.; Zurek, Wojciech H.

      2013-05-20

      The sum of the Holevo quantity (that bounds the capacity of quantum channels to transmit classical information about an observable) and the quantum discord (a measure of the quantumness of correlations of that observable) yields an observable-independent total given by the quantum mutual information. This split naturally delineates information about quantum systems accessible to observers – information that is redundantly transmitted by the environment – while showing that it is maximized for the quasi-classical pointer observable. Other observables are accessible only via correlations with the pointer observable. In addition, we prove an anti-symmetry property relating accessible information and discord. Itmore » shows that information becomes objective – accessible to many observers – only as quantum information is relegated to correlations with the global environment, and, therefore, locally inaccessible. Lastly, the resulting complementarity explains why, in a quantum Universe, we perceive objective classical reality while flagrantly quantum superpositions are out of reach.« less

    3. Absorbing State Phase Transition with Competing Quantum and Classical Fluctuations.

      PubMed

      Marcuzzi, Matteo; Buchhold, Michael; Diehl, Sebastian; Lesanovsky, Igor

      2016-06-17

      Stochastic processes with absorbing states feature examples of nonequilibrium universal phenomena. While the classical regime has been thoroughly investigated in the past, relatively little is known about the behavior of these nonequilibrium systems in the presence of quantum fluctuations. Here, we theoretically address such a scenario in an open quantum spin model which, in its classical limit, undergoes a directed percolation phase transition. By mapping the problem to a nonequilibrium field theory, we show that the introduction of quantum fluctuations stemming from coherent, rather than statistical, spin flips alters the nature of the transition such that it becomes first order. In the intermediate regime, where classical and quantum dynamics compete on equal terms, we highlight the presence of a bicritical point with universal features different from the directed percolation class in a low dimension. We finally propose how this physics could be explored within gases of interacting atoms excited to Rydberg states.

    4. Absorbing State Phase Transition with Competing Quantum and Classical Fluctuations

      NASA Astrophysics Data System (ADS)

      Marcuzzi, Matteo; Buchhold, Michael; Diehl, Sebastian; Lesanovsky, Igor

      2016-06-01

      Stochastic processes with absorbing states feature examples of nonequilibrium universal phenomena. While the classical regime has been thoroughly investigated in the past, relatively little is known about the behavior of these nonequilibrium systems in the presence of quantum fluctuations. Here, we theoretically address such a scenario in an open quantum spin model which, in its classical limit, undergoes a directed percolation phase transition. By mapping the problem to a nonequilibrium field theory, we show that the introduction of quantum fluctuations stemming from coherent, rather than statistical, spin flips alters the nature of the transition such that it becomes first order. In the intermediate regime, where classical and quantum dynamics compete on equal terms, we highlight the presence of a bicritical point with universal features different from the directed percolation class in a low dimension. We finally propose how this physics could be explored within gases of interacting atoms excited to Rydberg states.

    5. LGALS3 as a prognostic factor for classical Hodgkin's lymphoma.

      PubMed

      Koh, Young Wha; Jung, Se Jin; Park, Chan-Sik; Yoon, Dok Hyun; Suh, Cheolwon; Huh, Jooryung

      2014-10-01

      LGALS3, a member of the lectin family, has an important role in tumor progression through inhibition of apoptosis. LGALS3 shares several significant structural properties with BCL2. In this study, we examined the prognostic significance of LGALS3 and BCL2 in uniformly treated classical Hodgkin's lymphoma. Diagnostic tissues from 110 patients with uniformly treated classical Hodgkin's lymphoma were evaluated retrospectively by immunohistochemical analysis of LGALS3 and BCL2 expression. The median follow-up time was 6.2 years (range, 0.2-17.3 years). Twenty-seven patients (25%) expressed LGALS3 protein in Hodgkin/Reed-Sternberg cells, which was associated with poor overall survival and event-free survival (P=0.007 and P<0.001). Fifteen patients (14%) expressed BCL2 protein in Hodgkin/Reed-Sternberg cells, which was not associated with overall survival and event-free survival (P=0.928 and P=0.900).There was no correlation between LGALS3 and BCL2 expression (P=0.193). Multivariate analysis identified LGALS3 protein as an independent prognostic factor for event-free survival (P=0.007). Subgroup analysis according to the Ann Arbor stage of classical Hodgkin's lymphoma showed that LGALS3 protein expression had a prognostic value in limited-stage classical Hodgkin's lymphoma (P<0.001). The results of this study suggest that LGALS3 is an independent prognostic factor in classical Hodgkin's lymphoma, and may allow the identification of a subgroup of patients with limited-stage classical Hodgkin's lymphoma who require more intensive therapy.

    6. Classical conditioning differences associated with chronic pain: a systematic review.

      PubMed

      Harvie, Daniel S; Moseley, G Lorimer; Hillier, Susan L; Meulders, Ann

      2017-04-03

      Prominent clinical models of chronic pain propose a fundamental role of classical conditioning in the development of pain-related disability. If classical conditioning is key to this process, then people with chronic pain may show a different response to pain-related conditioned stimuli (CS) than healthy controls. We set out to determine whether this is the case by undertaking a comprehensive and systematic review of the literature. To identify studies comparing classical conditioning between people with chronic pain and healthy controls, the databases MEDLINE, PsychINFO, PsychARTICLES, Scopus, CINAHL, were searched using key words and MESH headings consistent with 'classical conditioning' AND 'pain'. Articles were included when a) pain-free control and chronic pain groups were included, and b) a differential classical conditioning design was used. The systematic search revealed seven studies investigating differences in classical conditioning between people with chronic pain and healthy controls. The included studies involved a total of 129 people with chronic pain (Fibromyalgia syndrome, Spinal pain, Hand pain, Irritable bowel syndrome), and 104 healthy controls. Outcomes included indices of pain-related conditioning such as unconditioned stimulus (US) expectancy and contingency awareness, self-report and physiological measures of pain-related fear, evaluative judgments of conditioned stimulus (CS) pleasantness, and muscular and cortical responses. Due to variability in outcomes, meta-analyses included a maximum of four studies. People with chronic pain tended to show reduced differential learning and flatter generalisation gradients with respect to US-expectancy and fear-potentiated eyeblink startle responses. Some studies demonstrated a propensity for greater muscular responses and perceptions of unpleasantness in response to pain-associated cues, relative to control cues.

    7. Two-slit experiment: quantum and classical probabilities

      NASA Astrophysics Data System (ADS)

      Khrennikov, Andrei

      2015-06-01

      Inter-relation between quantum and classical probability models is one of the most fundamental problems of quantum foundations. Nowadays this problem also plays an important role in quantum technologies, in quantum cryptography and the theory of quantum random generators. In this letter, we compare the viewpoint of Richard Feynman that the behavior of quantum particles cannot be described by classical probability theory with the viewpoint that quantum-classical inter-relation is more complicated (cf, in particular, with the tomographic model of quantum mechanics developed in detail by Vladimir Man'ko). As a basic example, we consider the two-slit experiment, which played a crucial role in quantum foundational debates at the beginning of quantum mechanics (QM). In particular, its analysis led Niels Bohr to the formulation of the principle of complementarity. First, we demonstrate that in complete accordance with Feynman's viewpoint, the probabilities for the two-slit experiment have the non-Kolmogorovian structure, since they violate one of basic laws of classical probability theory, the law of total probability (the heart of the Bayesian analysis). However, then we show that these probabilities can be embedded in a natural way into the classical (Kolmogorov, 1933) probability model. To do this, one has to take into account the randomness of selection of different experimental contexts, the joint consideration of which led Feynman to a conclusion about the non-classicality of quantum probability. We compare this embedding of non-Kolmogorovian quantum probabilities into the Kolmogorov model with well-known embeddings of non-Euclidean geometries into Euclidean space (e.g., the Poincaré disk model for the Lobachvesky plane).

    8. Derivation of the blackbody radiation spectrum from the equivalence principle in classical physics with classical electromagnetic zero-point radiation

      SciTech Connect

      Boyer, T.H.

      1984-03-15

      A derivation of Planck's spectrum including zero-point radiation is given within classical physics from recent results involving the thermal effects of acceleration through classical electromagnetic zero-point radiation. A harmonic electric-dipole oscillator undergoing a uniform acceleration a through classical electromagnetic zero-point radiation responds as would the same oscillator in an inertial frame when not in zero-point radiation but in a different spectrum of random classical radiation. Since the equivalence principle tells us that the oscillator supported in a gravitational field g = -a will respond in the same way, we see that in a gravitational field we can construct a perpetual-motion machine based on this different spectrum unless the different spectrum corresponds to that of thermal equilibrium at a finite temperature. Therefore, assuming the absence of perpetual-motion machines of the first kind in a gravitational field, we conclude that the response of an oscillator accelerating through classical zero-point radiation must be that of a thermal system. This then determines the blackbody radiation spectrum in an inertial frame which turns out to be exactly Planck's spectrum including zero-point radiation.

    9. On the classical roots of the Einstein Podolsky Rosen paradox

      NASA Astrophysics Data System (ADS)

      Lando, A.; Bringuier, E.

      2008-03-01

      The 1935 debate opposing Einstein, Podolsky and Rosen to Bohr elicited so many comments and developments, both theoretical and experimental, until this day, that the main point at stake at that time can be overlooked by modern readers, especially students. This paper draws the reader's attention to the historical background of Einstein's paper and Bohr's reply. We show that Einstein's definition of a complete physical theory is taken from Mach's criticism of atomic theory based upon classical-mechanical views. As for Bohr's definition of physical reality, it can be simply understood by reference to classical physics although it was embedded in the quantum-mechanical formalism.

    10. Classical and revival time periods of confined harmonic oscillator

      NASA Astrophysics Data System (ADS)

      Ghosh, P.; Ghosh, S.; Bera, N.

      2015-02-01

      We have used perturbation theory to compute energy eigenvalues, classical and the revival time periods for a one-dimensional harmonic oscillator confined in a box. First we have considered a simple harmonic oscillator as the unperturbed problem and boundary as perturbation. In next case, free particle in a box is considered as unperturbed problem that has been perturbed by a parabolic potential. We have used Fourier Grid Hamiltonian method to estimate classical and revival time period for the confined harmonic oscillator, which crosses smoothly from free particle in a box to a simple harmonic oscillator.

    11. Octic Anharmonic Oscillators: Perturbed Coherent States and the Classical Limit

      NASA Astrophysics Data System (ADS)

      Jafarpour, Mojtaba; Tahamtan, Tayebeh

      2009-02-01

      We use the Poincaré-Linstedt method to find a classical perturbation solution to the octic anharmonic oscillator. Next, we derive perturbed coherent states for this system, calculate the expectation value of the hat{x} -operator in them and enforce a limiting process to retrieve the classical result from the corresponding quantum one. We have observed a frequency shift proportional to the sixth power of the amplitude for this system. Our results are in agreement with those obtained from Taylor-series method.

    12. [Reinterventions in classic and laparoscopic surgery of biliary ducts].

      PubMed

      Lese, M; Naghi, I; Pop, C

      2000-01-01

      The study suggests to make a comparative analysis between the complications happened after classic and laparoscopic surgery require a surgical reintervention. The study was realised in the Surgical Department of the Districtual Hospital Baia Mare between 27.04.1997-27.04.1999, which means the precursory year of beginning laparoscopic surgery and the first year with experience in laparoscopic surgery. The conclusions of this study prove that the number of reinterventions after laparoscopic surgery is less than after classic surgery of biliary ducts.

    13. A semiclassical tunneling model for use in classical trajectory simulations

      SciTech Connect

      Makri, N.; Miller, W.H. )

      1989-10-01

      A semiclassical model for tunneling from one classically allowed region on a potential energy surface to another is described. The principal feature of this model, compared to earlier (more rigorous'') multidimensional semiclassical tunneling theories, is that it can be implemented in a straightforward way within the framework of a standard classical trajectory simulation. Applications to several examples of unimolecular isomerization and unimolecular dissociation show that the model is capable of providing excellent results over a wide range of conditions (i.e., coupling strengths, different symmetries of couplings, etc.)

    14. Simple universal models capture all classical spin physics.

      PubMed

      De las Cuevas, Gemma; Cubitt, Toby S

      2016-03-11

      Spin models are used in many studies of complex systems because they exhibit rich macroscopic behavior despite their microscopic simplicity. Here, we prove that all the physics of every classical spin model is reproduced in the low-energy sector of certain "universal models," with at most polynomial overhead. This holds for classical models with discrete or continuous degrees of freedom. We prove necessary and sufficient conditions for a spin model to be universal and show that one of the simplest and most widely studied spin models, the two-dimensional Ising model with fields, is universal. Our results may facilitate physical simulations of Hamiltonians with complex interactions.

    15. Towards classical spectrum generating algebras for f-deformations

      NASA Astrophysics Data System (ADS)

      Kullock, Ricardo; Latini, Danilo

      2016-01-01

      In this paper we revise the classical analog of f-oscillators, a generalization of q-oscillators given in Man'ko et al. (1997) [8], in the framework of classical spectrum generating algebras (SGA) introduced in Kuru and Negro (2008) [9]. We write down the deformed Poisson algebra characterizing the entire family of non-linear oscillators and construct its general solution algebraically. The latter, covering the full range of f-deformations, shows an energy dependence both in the amplitude and the frequency of the motion.

    16. Efficient classical simulation of continuous variable quantum information processes.

      PubMed

      Bartlett, Stephen D; Sanders, Barry C; Braunstein, Samuel L; Nemoto, Kae

      2002-03-04

      We obtain sufficient conditions for the efficient simulation of a continuous variable quantum algorithm or process on a classical computer. The resulting theorem is an extension of the Gottesman-Knill theorem to continuous variable quantum information. For a collection of harmonic oscillators, any quantum process that begins with unentangled Gaussian states, performs only transformations generated by Hamiltonians that are quadratic in the canonical operators, and involves only measurements of canonical operators (including finite losses) and suitable operations conditioned on these measurements can be simulated efficiently on a classical computer.

    17. The Orbital Period of the Classical Nova V458 Vul

      NASA Astrophysics Data System (ADS)

      Goranskij, V. P.; Metlova, N. V.; Barsukova, E. A.; Burenkov, A. N.; Soloviev, V. Ya.

      2008-07-01

      Classical nova V458 Vul (N Vul 2007 No.1) was detected as a supersoft X-ray source (SSS) by the Swift XRT several times in the time range between 2007 October 18 and 2008 June 18 (J. Drake et al., ATel #1246 and #1603). Our V photometry shows the plateau in the light curve continued since January till June 2008. This feature accompanies usually the SSS phases in some classical novae. The fragmentary monitoring during plateau shows night- to-night variability with the amplitudes between 1.2 and 0.4 mag and rapid variability by 0.1 mag in the time scale of an hour.

    18. Orthogonal polynomials, Laguerre Fock space, and quasi-classical asymptotics

      NASA Astrophysics Data System (ADS)

      Engliš, Miroslav; Ali, S. Twareque

      2015-07-01

      Continuing our earlier investigation of the Hermite case [S. T. Ali and M. Engliš, J. Math. Phys. 55, 042102 (2014)], we study an unorthodox variant of the Berezin-Toeplitz quantization scheme associated with Laguerre polynomials. In particular, we describe a "Laguerre analogue" of the classical Fock (Segal-Bargmann) space and the relevant semi-classical asymptotics of its Toeplitz operators; the former actually turns out to coincide with the Hilbert space appearing in the construction of the well-known Barut-Girardello coherent states. Further extension to the case of Legendre polynomials is likewise discussed.

    19. Classical Bifurcation at the Transition from Rabi to Josephson Dynamics

      SciTech Connect

      Zibold, Tilman; Nicklas, Eike; Gross, Christian; Oberthaler, Markus K.

      2010-11-12

      We report on the experimental demonstration of the internal bosonic Josephson effect in a rubidium spinor Bose-Einstein condensate. The measurement of the full time dynamics in phase space allows the characterization of the theoretically predicted {pi}-phase modes and quantitatively confirms analytical predictions, revealing a classical bifurcation. Our results suggest that this system is a model system which can be tuned from classical to the quantum regime and thus is an important step towards the experimental investigation of entanglement generation close to critical points.

    20. AG Pegasi - now a classical symbiotic star in outburst?

      NASA Astrophysics Data System (ADS)

      Tomov, T. V.; Stoyanov, K. A.; Zamanov, R. K.

      2016-11-01

      Optical spectroscopy study of the recent AG Pegasi (AG Peg) outburst observed during the second half of 2015 is presented. Considerable variations of the intensity and the shape of the spectral features as well as the changes of the hot component parameters, caused by the outburst, are discussed and certain similarities between the outburst of AG Peg and the outburst of a classical symbiotic stars are shown. It seems that after the end of the symbiotic nova phase, AG Peg became a member of the classical symbiotic stars group.