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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, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false ACORA Garwood Classic Offshore Race, Algonac, MI. 100.913 Section 100.913 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.913 ACORA Garwood Classic Offshore Race, Algonac, MI....

  2. 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 §...

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

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 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 §...

  4. 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 §...

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

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 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 §...

  6. Master Plan for Educational Facilities: Garwood, Union County, New Jersey.

    ERIC Educational Resources Information Center

    Engelhardt and Engelhardt, Inc., Purdy Station, NY.

    Garwood, New Jersey, is a small borough of 0.69 square miles with an estimated population in 1978 of 4,856 persons. This master plan for educational facilities begins with an overview of the district that describes its beginnings as an industrial community. A number of maps illustrate characteristics of the area including its topography,…

  7. Chemical characterization of microbial-dominated soil organic matter in the Garwood Valley, Antarctica

    NASA Astrophysics Data System (ADS)

    Feng, Xiaojuan; Simpson, André J.; Gregorich, Edward G.; Elberling, Bo; Hopkins, David W.; Sparrow, Ashley D.; Novis, Philip M.; Greenfield, Lawrence G.; Simpson, Myrna J.

    2010-11-01

    Despite its harsh environmental conditions, terrestrial Antarctica contains a relatively large microbial biomass. Natural abundance carbon and nitrogen stable isotope signatures of organic materials in the dry valleys indicate mixed provenance of the soil organic matter (SOM) with varying proportions of contributions from lichens, mosses, lake-derived algae and cyanobacteria. Here we employed two complementary analytical techniques, biomarker measurements by gas chromatography/mass spectrometry and solution-state 1H nuclear magnetic resonance spectroscopy, to provide further information at a molecular-level about the composition and possible source of SOM in the Garwood Valley, Antarctica. The predominance of branched alkanes and short-chain lipids in the solvent extracts indicates that the primary contribution to the SOM was microbial-derived. Chemical structures in the NaOH extracts from soils were also dominated by amide, peptides, and a CH 3-dominating aliphatic region that were characteristic of microbial signatures. Furthermore, the SOM in the Garwood Valley contained compounds that were different from those in the cyanobacteria-dominated mat from a nearby lake (including monoethyl alkanes and enriched side-chain protons). This observation suggests that easily degradable carbon sources from the nearby lake did not dominate the SOM, which is consistent with a fast turnover of the mat-derived organic matter found in the valley. This study highlights the important role of native soil microbes in the carbon transformation and biogeochemistry in terrestrial Antarctica.

  8. 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

  9. 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…

  10. 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.

  11. 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.

  12. 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…

  13. 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…

  14. Fermions from classical statistics

    SciTech Connect

    Wetterich, C.

    2010-12-15

    We describe fermions in terms of a classical statistical ensemble. The states {tau} of this ensemble are characterized by a sequence of values one or zero or a corresponding set of two-level observables. Every classical probability distribution can be associated to a quantum state for fermions. If the time evolution of the classical probabilities p{sub {tau}} amounts to a rotation of the wave function q{sub {tau}}(t)={+-}{radical}(p{sub {tau}}(t)), we infer the unitary time evolution of a quantum system of fermions according to a Schroedinger equation. We establish how such classical statistical ensembles can be mapped to Grassmann functional integrals. Quantum field theories for fermions arise for a suitable time evolution of classical probabilities for generalized Ising models.

  15. 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)

  16. Injuries in classical ballet.

    PubMed

    Quirk, R

    1984-11-01

    The specialised medical knowledge about dancers' injuries is negligible compared with that which surrounds sports medicine. The author discusses his experience in the management of more than 2000 injuries sustained by dancers of classical ballet. PMID:6151832

  17. Entanglement with Classical Spinors

    NASA Astrophysics Data System (ADS)

    Baylis, William E.; Johnson, Crystal

    2004-05-01

    The spinor formulation of classical dynamics, which arises naturally in Clifford algebra approaches, describes particle dynamics in terms of spinor amplitudes and gives quantum mechanical, spin-1/2 form to many classical expressions for particles whose dynamics can be represented by single spinor fields. Here we use tensor products of the algebra of physical space (APS)[1] to explore the quantum/classical interface and provide insight into quantum properties and, in particular, entanglement in multiparticle spin-1/2 systems. Entanglement in mixed-state systems is seen as spinor (Â"quantumÂ") correlation beyond the maximum possible with classical frequencies or probabilities. The relevance to systems of qubits in a quantum computer is elaborated. [1] W. E. Baylis, Â"Applications of Clifford Algebras in PhysicsÂ", in Lectures on Clifford (Geometric) Algebras and Applications, R. Ablamowicz and G. Sobczyk, eds., Birkhäuser Boston, 2004.

  18. 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.

  19. Subnuclear realm: classical in quantum and quantum in classical

    SciTech Connect

    Kosyakov, B. P.

    1999-03-11

    Exact solutions in the classical Yang-Mills-Wong theory enable explaining a number of enigmatic classical features of subnuclear realm. Moreover, they reveal some unexpected quantum features of this classical treatment.

  20. Classical dynamical localization.

    PubMed

    Guarneri, Italo; Casati, Giulio; Karle, Volker

    2014-10-24

    We consider classical models of the kicked rotor type, with piecewise linear kicking potentials designed so that momentum changes only by multiples of a given constant. Their dynamics display quasilocalization of momentum, or quadratic growth of energy, depending on the arithmetic nature of the constant. Such purely classical features mimic paradigmatic features of the quantum kicked rotor, notably dynamical localization in momentum, or quantum resonances. We present a heuristic explanation, based on a classical phase space generalization of a well-known argument, that maps the quantum kicked rotor on a tight-binding model with disorder. Such results suggest reconsideration of generally accepted views that dynamical localization and quantum resonances are a pure result of quantum coherence. PMID:25379918

  1. 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)

  2. 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…

  3. 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…

  4. 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.

  5. 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); (3) "Hawthorne: A Study in…

  6. 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)

  7. 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)

  8. The Classical Cake Problem

    ERIC Educational Resources Information Center

    Nelson, Norman N.; Fisch, Forest N.

    1973-01-01

    Discussed are techniques of presentation and solution of the Classical Cake Problem. A frosted cake with a square base is to be cut into n pieces with the volume of cake and frosting the same for each piece. Needed are minimal geometric concepts and the formula for the volume of a prism. (JP)

  9. 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…

  10. 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…

  11. Classical higgs fields

    NASA Astrophysics Data System (ADS)

    Sardanashvily, G. A.

    2014-12-01

    We consider a classical gauge theory on a principal fiber bundle P → X in the case where its structure group G is reduced to a subgroup H in the presence of classical Higgs fields described by global sections of the quotient fiber bundle P/H → X. We show that matter fields with the exact symmetry group H in such a theory are described by sections of the composition fiber bundle Y → P/H → X, where Y → P/H is the fiber bundle with the structure group H, and the Lagrangian of these sections is factored by virtue of the vertical covariant differential determined by a connection on the fiber bundle Y → P/H.

  12. Revisiting a Classic

    ERIC Educational Resources Information Center

    Rogers, Ibram

    2008-01-01

    As a 26-year-old English teacher in 1958, Chinua Achebe had no idea that the book he was writing would become a literary classic, not only in Africa but also throughout the world. He could only try to articulate the feelings he had for his countrymen and women. Achebe had a burning desire to tell the true story of Africa and African humanity. The…

  13. What was classical genetics?

    PubMed

    Waters, C Kenneth

    2004-12-01

    I present an account of classical genetics to challenge theory-biased approaches in the philosophy of science. Philosophers typically assume that scientific knowledge is ultimately structured by explanatory reasoning and that research programs in well-established sciences are organized around efforts to fill out a central theory and extend its explanatory range. In the case of classical genetics, philosophers assume that the knowledge was structured by T. H. Morgan's theory of transmission and that research throughout the later 1920s, 30s, and 40s was organized around efforts to further validate, develop, and extend this theory, I show that classical genetics was structured by an integration of explanatory reasoning (associated with the transmission theory) and investigative strategies (such as the 'genetic approach'). The investigative strategies, which have been overlooked in historical and philosophical accounts, were as important as the so-called laws of Mendelian genetics. By the later 1920s, geneticists of the Morgan school were no longer organizing research around the goal of explaining inheritance patterns; rather, they were using genetics to investigate a range of biological phenomena that extended well beyond the explanatory domain of transmission theories. Theory-biased approaches in history and philosophy of science fail to reveal the overall structure of scientific knowledge and obscure the way it functions. PMID:15682554

  14. 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.

  15. 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…

  16. 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.

  17. 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.

  18. Quantum transitions between classical histories

    NASA Astrophysics Data System (ADS)

    Hartle, James; Hertog, Thomas

    2015-09-01

    In a quantum theory of gravity spacetime behaves classically when quantum probabilities are high for histories of geometry and field that are correlated in time by the Einstein equation. Probabilities follow from the quantum state. This quantum perspective on classicality has important implications. (a) Classical histories are generally available only in limited patches of the configuration space on which the state lives. (b) In a given patch, states generally predict relative probabilities for an ensemble of possible classical histories. (c) In between patches classical predictability breaks down and is replaced by quantum evolution connecting classical histories in different patches. (d) Classical predictability can break down on scales well below the Planck scale, and with no breakdown in the classical equations of motion. We support and illustrate (a)-(d) by calculating the quantum transition across the de Sitter-like throat connecting asymptotically classical, inflating histories in the no-boundary quantum state. This supplies probabilities for how a classical history on one side transitions and branches into a range of classical histories on the opposite side. We also comment on the implications of (a)-(d) for the dynamics of black holes and eternal inflation.

  19. Quantum Computing's Classical Problem, Classical Computing's Quantum Problem

    NASA Astrophysics Data System (ADS)

    Van Meter, Rodney

    2014-08-01

    Tasked with the challenge to build better and better computers, quantum computing and classical computing face the same conundrum: the success of classical computing systems. Small quantum computing systems have been demonstrated, and intermediate-scale systems are on the horizon, capable of calculating numeric results or simulating physical systems far beyond what humans can do by hand. However, to be commercially viable, they must surpass what our wildly successful, highly advanced classical computers can already do. At the same time, those classical computers continue to advance, but those advances are now constrained by thermodynamics, and will soon be limited by the discrete nature of atomic matter and ultimately quantum effects. Technological advances benefit both quantum and classical machinery, altering the competitive landscape. Can we build quantum computing systems that out-compute classical systems capable of some logic gates per month? This article will discuss the interplay in these competing and cooperating technological trends.

  20. The classic: Bone morphogenetic protein.

    PubMed

    Urist, Marshall R; Strates, Basil S

    2009-12-01

    This Classic Article is a reprint of the original work by Marshall R. Urist and Basil S. Strates, Bone Morphogenetic Protein. An accompanying biographical sketch of Marshall R. Urist, MD is available at DOI 10.1007/s11999-009-1067-4; a second Classic Article is available at DOI 10.1007/s11999-009-1069-2; and a third Classic Article is available at DOI 10.1007/s11999-009-1070-9. The Classic Article is copyright 1971 by Sage Publications Inc. Journals and is reprinted with permission from Urist MR, Strates BS. Bone morphogenetic protein. J Dent Res. 1971;50:1392-1406. PMID:19727989

  1. 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.

  2. Return to the Classics

    NASA Astrophysics Data System (ADS)

    Shen, Y. R.

    1990-10-01

    The two seminal papers that set the theoretical foundation of nonlinear optics were written by Bloembergen and coworkers in 1962. The first one on "Interaction between Light Waves in a Nonlinear Dielectric" by Armstrong, Bloembergen, Ducuing and Pershan1 describes mainly the wave mixing process, aside from discussions on microscopic expressions for nonlinear susceptibilities, local-field corrections, energy relations, and others. The second one on "Light Waves at the Boundary of Nonlinear Media" by Bloembergen and Pershan2 considers the boundary effects on wave mixing. Both papers are clear in concepts, but the mathematical derivations are rather difficult to digest. While most people in nonlinear optics have studied the papers, few have attempted to reproduce the equations in them. Recently, through teaching, I have found that even the derivation of an expression for the transmitted second harmonic field, ET, in a nonlinear uniaxial medium is not so simple. The ABDP paper used the slowly varying amplitude approximation to obtain ET, whereas the BP paper found ET more rigorously by taking the boundary conditions explicitly into account. It is, however, not trivial to see whether the two expressions of ET from the two papers are consistent with each other. This is actually an important issue considering that the result is the basis of all wave mixing problems. As a tribute to Prof. Bloembergen on the occasion of his 70th birday, I take the liberty to review the derivations in these masterpieces, fill in the intermediate steps in the derivations, and discuss the consistency. Hopefully, this could serve, in a small way, as a supplement to the Bloembergen classics in nonlinear optics.

  3. Quantum mechanics from classical statistics

    SciTech Connect

    Wetterich, C.

    2010-04-15

    Quantum mechanics can emerge from classical statistics. A typical quantum system describes an isolated subsystem of a classical statistical ensemble with infinitely many classical states. The state of this subsystem can be characterized by only a few probabilistic observables. Their expectation values define a density matrix if they obey a 'purity constraint'. Then all the usual laws of quantum mechanics follow, including Heisenberg's uncertainty relation, entanglement and a violation of Bell's inequalities. No concepts beyond classical statistics are needed for quantum physics - the differences are only apparent and result from the particularities of those classical statistical systems which admit a quantum mechanical description. Born's rule for quantum mechanical probabilities follows from the probability concept for a classical statistical ensemble. In particular, we show how the non-commuting properties of quantum operators are associated to the use of conditional probabilities within the classical system, and how a unitary time evolution reflects the isolation of the subsystem. As an illustration, we discuss a classical statistical implementation of a quantum computer.

  4. 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…

  5. 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.…

  6. 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)

  7. Classic African American Children's Literature

    ERIC Educational Resources Information Center

    McNair, Jonda C.

    2010-01-01

    The purpose of this article is to assert that there are classic African American children's books and to identify a sampling of them. The author presents multiple definitions of the term classic based on the responses of children's literature experts and relevant scholarship. Next, the manner in which data were collected and analyzed in regard to…

  8. 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.

  9. Classical dynamics of quantum entanglement.

    PubMed

    Casati, Giulio; Guarneri, Italo; Reslen, Jose

    2012-03-01

    We analyze numerically the dynamical generation of quantum entanglement in a system of two interacting particles, started in a coherent separable state, for decreasing values of ℏ. As ℏ→0 the entanglement entropy, computed at any finite time, converges to a finite nonzero value. The limit law that rules the time dependence of entropy is well reproduced by purely classical computations. Its general features can be explained by simple classical arguments, which expose the different ways entanglement is generated in systems that are classically chaotic or regular. PMID:22587162

  10. Anderson localization from classical trajectories

    NASA Astrophysics Data System (ADS)

    Brouwer, Piet W.; Altland, Alexander

    2008-08-01

    We show that Anderson localization in quasi-one-dimensional conductors with ballistic electron dynamics, such as an array of ballistic chaotic cavities connected via ballistic contacts, can be understood in terms of classical electron trajectories only. At large length scales, an exponential proliferation of trajectories of nearly identical classical action generates an abundance of interference terms, which eventually leads to a suppression of transport coefficients. We quantitatively describe this mechanism in two different ways: the explicit description of transition probabilities in terms of interfering trajectories, and an hierarchical integration over fluctuations in the classical phase space of the array cavities.

  11. 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.

  12. The classical microwave frequency standards

    NASA Technical Reports Server (NTRS)

    Busca, Giovanni; Thomann, Pierre; Laurent-Guy, Bernier; Willemin, Philippe; Schweda, Hartmut S.

    1990-01-01

    Some key problems are presented encountered in the classical microwave frequency standards which are still not solved today. The point of view expressed benefits from the experience gained both in the industry and in the research lab, on the following classical microwave frequency standards: active and passive H, conventional and laser pumped Cs beam tube, small conventional and laser pumped Rubidium. The accent is put on the Rubidium standard.

  13. Electrostatics interactions in classical simulations.

    PubMed

    Cisneros, G Andrés; Babin, Volodymyr; Sagui, Celeste

    2013-01-01

    Electrostatic interactions are crucial for both the accuracy and performance of atomistic biomolecular simulations. In this chapter we review well-established methods and current developments aiming at efficiency and accuracy. Specifically, we review the classical Ewald summations, particle-particle particle-method particle-method Ewald algorithms, multigrid, fast multipole, and local methods. We also highlight some recent developments targeting more accurate, yet classical, representation of the molecular charge distribution. PMID:23034752

  14. 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.

  15. 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.

  16. Classicality of a quantum oscillator

    NASA Astrophysics Data System (ADS)

    Ahmadzadegan, Aida; Mann, Robert B.; Terno, Daniel R.

    2016-03-01

    Gaussian quantum systems exhibit many explicitly quantum effects but can be simulated classically. By using both the Hilbert space (Koopman) and the phase-space (Moyal) formalisms we investigate how robust this classicality is. We find failures of consistency of the dynamics of hybrid classical-quantum systems from both perspectives. By demanding that no unobservable operators couple to the quantum sector in the Koopmanian formalism, we show that the classical equations of motion act on their quantum counterparts without experiencing any back reaction, resulting in nonconservation of energy in the quantum system. By using the phase-space formalism we study the short-time evolution of the moment equations of a hybrid classical-Gaussian quantum system and observe violations of the Heisenberg uncertainty relation in the quantum sector for a broad range of initial conditions. We estimate the timescale for these violations, which is generically rather short. This inconsistency indicates that while many explicitly quantum effects can be represented classically, quantum aspects of the system cannot be fully masked. We comment on the implications of our results for quantum gravity.

  17. 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.

  18. 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…

  19. 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...

  20. Classical picture of postexponential decay

    SciTech Connect

    Torrontegui, E.; Muga, J. G.; Martorell, J.; Sprung, D. W. L.

    2010-04-15

    Postexponential decay of the probability density of a quantum particle leaving a trap can be reproduced accurately, except for interference oscillations at the transition to the postexponential regime, by means of an ensemble of classical particles emitted with constant probability per unit time and the same half-life as the quantum system. The energy distribution of the ensemble is chosen to be identical to the quantum distribution, and the classical point source is located at the scattering length of the corresponding quantum system. A one-dimensional example is provided to illustrate the general argument.

  1. Measurement-Based Classical Computation

    NASA Astrophysics Data System (ADS)

    Hoban, Matty J.; Wallman, Joel J.; Anwar, Hussain; Usher, Naïri; Raussendorf, Robert; Browne, Dan E.

    2014-04-01

    Measurement-based quantum computation (MBQC) is a model of quantum computation, in which computation proceeds via adaptive single qubit measurements on a multiqubit quantum state. It is computationally equivalent to the circuit model. Unlike the circuit model, however, its classical analog is little studied. Here we present a classical analog of MBQC whose computational complexity presents a rich structure. To do so, we identify uniform families of quantum computations [refining the circuits introduced by Bremner et al. Proc. R. Soc. A 467, 459 (2010)] whose output is likely hard to exactly simulate (sample) classically. We demonstrate that these circuit families can be efficiently implemented in the MBQC model without adaptive measurement and, thus, can be achieved in a classical analog of MBQC whose resource state is a probability distribution which has been created quantum mechanically. Such states (by definition) violate no Bell inequality, but, if widely held beliefs about computational complexity are true, they, nevertheless, exhibit nonclassicality when used as a computational resource—an imprint of their quantum origin.

  2. 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…

  3. Augmenting a Classical Electrochemical Demonstration.

    ERIC Educational Resources Information Center

    Yochum, Susan M.; Luoma, John R.

    1995-01-01

    Presents an augmentation of a classical electrochemical demonstration that addresses the learning styles of the students and teaches electrochemistry in a concrete manner. Enables each student to see each event clearly, repeatedly, or in stop-action mode and enables students to improve their own mental models by providing them with a visually…

  4. Classical Virasoro irregular conformal block

    NASA Astrophysics Data System (ADS)

    Rim, Chaiho; Zhang, Hong

    2015-07-01

    Virasoro irregular conformal block with arbitrary rank is obtained for the classical limit or equivalently Nekrasov-Shatashvili limit using the beta-deformed irregular matrix model (Penner-type matrix model for the irregular conformal block). The same result is derived using the generalized Mathieu equation which is equivalent to the loop equation of the irregular matrix model.

  5. 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…

  6. CLASSICAL BIOLOGICAL CONTROL OF WEEDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Classical biological control of weeds is an important tool for managing invasive alien plants that have become too widespread to control by conventional methods. It involves the discovery and release of naturally occurring species of natural enemies (insects, mites or pathogens) to control a pest (...

  7. Holographic entanglement beyond classical gravity

    NASA Astrophysics Data System (ADS)

    Barrella, Taylor; Dong, Xi; Hartnoll, Sean A.; Martin, Victoria L.

    2013-09-01

    The Rényi entropies and entanglement entropy of 1+1 CFTs with gravity duals can be computed by explicit construction of the bulk spacetimes dual to branched covers of the boundary geometry. At the classical level in the bulk this has recently been shown to reproduce the conjectured Ryu-Takayanagi formula for the holographic entanglement entropy. We study the one-loop bulk corrections to this formula. The functional determinants in the bulk geometries are given by a sum over certain words of generators of the Schottky group of the branched cover. For the case of two disjoint intervals on a line we obtain analytic answers for the one-loop entanglement entropy in an expansion in small cross-ratio. These reproduce and go beyond anticipated universal terms that are not visible classically in the bulk. We also consider the case of a single interval on a circle at finite temperature. At high temperatures we show that the one-loop contributions introduce expected finite size corrections to the entanglement entropy that are not present classically. At low temperatures, the one-loop corrections capture the mixed nature of the density matrix, also not visible classically below the Hawking-Page temperature.

  8. 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.

  9. Prequantum Classical Statistical Field Theory: Fundamentals

    SciTech Connect

    Khrennikov, Andrei

    2011-03-28

    We present fundamentals of a prequantum model with hidden variables of the classical field type. In some sense this is the comeback of classical wave mechanics. Our approach also can be considered as incorporation of quantum mechanics into classical signal theory. All quantum averages (including correlations of entangled systems) can be represented as classical signal averages and correlations.

  10. 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.

  11. Classicality in discrete Wigner functions

    SciTech Connect

    Cormick, Cecilia; Galvao, Ernesto F.; Gottesman, Daniel; Paz, Juan Pablo; Pittenger, Arthur O.

    2006-01-15

    Gibbons et al., [Phys. Rev. A 70, 062101 (2004)] have recently defined discrete Wigner functions W to represent quantum states in a Hilbert space with finite dimension. We show that such a class of Wigner functions W can be defined so that the only pure states having non-negative W for all such functions are stabilizer states, as conjectured by Galvao, [Phys. Rev. A 71, 042302 (2005)]. We also show that the unitaries preserving non-negativity of W for all definitions of W in the class form a subgroup of the Clifford group. This means pure states with non-negative W and their associated unitary dynamics are classical in the sense of admitting an efficient classical simulation scheme using the stabilizer formalism.

  12. Classical and Recurrent Nova Models

    NASA Astrophysics Data System (ADS)

    José, Jordi; Casanova, Jordi; García-Berro, Enrique; Hernanz, Margarita; Shore, Steven N.; Calder, Alan C.

    2013-01-01

    Remarkable progress in the understanding of nova outbursts has been achieved through combined efforts in photometry, spectroscopy and numerical simulations. According to the thermonuclear runaway model, novae are powered by thermonuclear explosions in the hydrogen-rich envelopes transferred from a low-mass stellar companion onto a close white dwarf star. Extensive numerical simulations in 1-D have shown that the accreted envelopes attain peak temperatures ranging between 108 and 4 × 108 K, for about several hundred seconds, hence allowing extensive nuclear processing which eventually shows up in the form of nucleosynthetic fingerprints in the ejecta. Indeed, it has been claimed that novae can play a certain role in the enrichment of the interstellar medium through a number of intermediate-mass elements. This includes 17O, 15N, and 13C, systematically overproduced with respect to solar abundances, plus a lower contribution in a number of other species (A < 40), such as 7Li, 19F, or 26Al. At the turn of the XXI Century, classical novae have entered the era of multidimensional models, which provide a new insight into the physical mechanisms that drive mixing at the core-envelope interface. In this review, we will present hydrodynamic models of classical novae, from the onset of accretion up to the explosion and ejection stages, both for classical and recurrent novae, with special emphasis on their gross observational properties and their associated nucleosynthesis. The impact of nuclear uncertainties on the final yields will be discussed. Recent results from 2-D models of mixing during classical nova outbursts will also be presented.

  13. 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.

  14. Classical music and the teeth.

    PubMed

    Eramo, Stefano; Di Biase, Mary Jo; De Carolis, Carlo

    2013-01-01

    Teeth and their pathologies are frequent themes in classical music. The teeth have inspired popular songwriters such as Thomas Crecquillon, Carl Loewe, Amilcare Ponchielli & Christian Sinding; as well as composers whose works are still played all over the world, such as Robert Schumann and Jacques Offenbach. This paper examines several selections in which the inspiring theme is the teeth and the pain they can cause, from the suffering of toothache, to the happier occasion of a baby's first tooth. PMID:23691776

  15. Instantaneous fields in classical electrodynamics

    NASA Astrophysics Data System (ADS)

    Heras, J. A.

    2005-01-01

    In this paper we express the retarded fields of Maxwell's theory in terms of the instantaneous fields of a Galilei-invariant electromagnetic and we find the vector function χL whose spatial and temporal derivatives transform the Euclidean fields into the retarded ones. We conclude that the instantaneous fields can formally be introduced as unphysical objects into classical electrodynamics which can be used to find the physical retarded fields.

  16. 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

  17. Classical Histories in Hamiltonian Systems

    NASA Astrophysics Data System (ADS)

    Kouletsis, Ioannis

    2001-08-01

    The incompatibility between the treatment of time in the classical and in the quantum theory results in the so-called problem of time in canonical quantum gravity. For this reason, attempts have been made to devise algorithms of quantization which accomodate the covariance of the classical theory from the outset. One of the most prominent of these attempts is based on the notion of continuous histories (Isham and Linden) in the context of the consistent histories approach to quantum theory (Griffiths, Omnes, Gell-Mann and Hartle). By the term continuous histories it is implied that the canonical fields and the symplectic structure of the theory depend on time as well as space. The aim of this thesis (in the form it was submitted to the University of London, February 2000) is to show that, even at the purely classical level, a history approach has several advantages (compared to its equal-time counterpart) when it comes to discussing spacetime issues. This is illustrated here by reframing and generalizing the derivation of geometrodynamics from first principles (Hojman, Kuchar, Teitelboim) in the language of the history phase space.

  18. Entanglement in the classical limit: Quantum correlations from classical probabilities

    SciTech Connect

    Matzkin, A.

    2011-08-15

    We investigate entanglement for a composite closed system endowed with a scaling property which allows the dynamics to be kept invariant while the effective Planck constant ({Dirac_h}/2{pi}){sub eff} of the system is varied. Entanglement increases as ({Dirac_h}/2{pi}){sub eff}{yields}0. Moreover, for sufficiently low ({Dirac_h}/2{pi}){sub eff} the evolution of the quantum correlations, encapsulated, for example, in the quantum discord, can be obtained from the mutual information of the corresponding classical system. We show this behavior is due to the local suppression of path interferences in the interaction that generates the entanglement.

  19. 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

  20. 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.

  1. 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.

  2. Recent developments in classical relativity

    NASA Astrophysics Data System (ADS)

    Schmidt, B. G.

    2001-10-01

    In the period spanned by the Texas meetings,-the term ``classical relativity'' was not yet coined 40 years ago-the notions of gravitational collapse, gravitational radiation singularities and black hole where in the center of almost all investigations and developments. 40 years ago black holes were exotic theoretical concepts far from reality. Now they seem to exist all over the univers. In the last 40 years a scenarium describing the collaps or collision of stellar objects or BHs has formed. In my talk I want to outline this picture, tell you which parts are firmly established and where the big open questions are. .

  3. Classical Lagrange Functions for the SME

    NASA Astrophysics Data System (ADS)

    Russell, N.

    2011-12-01

    A technique is presented for finding the classical Lagrange function corresponding to a given dispersion relation. This allows us to study the classical analogue of the Standard-Model Extension. Developments are discussed.

  4. Classically spinning and isospinning solitons

    SciTech Connect

    Battye, Richard A.; Haberichter, Mareike

    2012-09-26

    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.

  5. 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.

  6. Classical and eclipse optical choppers

    NASA Astrophysics Data System (ADS)

    Duma, Virgil-Florin

    2013-03-01

    The paper presents some of our advances in the study and development of optical choppers. The modulation functions we have studied for classical choppers are pointed out - for top-hat (constant intensity) light beam distributions. The eclipse choppers that, to the best of our knowledge we have introduced are also presented. We thus point out the differences between the profiles of light (laser) impulses produced by the classical devices (with rotating wheels with windows with linear edges) and the novel eclipse choppers - under patent (with windows with circular edges that produce for the circular-shaped section of the laser beam in the plane of the wheel a planetary eclipse-like effect - from which the name we have proposed for this type of device). The most convenient (from the technological and from the cost point of view) solution, with wheels with circular holes is also obtained. The advantages and the drawbacks of the various devices are discussed. Both a theoretical and an experimental approach are considered. The latter is done on a chopper module we have constructed, with prototype chopper wheels we have designed and manufactured. Throughout the study, top-hat laser beams are considered, as they are most used in laser manufacturing applications. The perspective of conducting the study on other light beams distributions (e.g., Gaussian) is also pointed out.

  7. 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. PMID:26219880

  8. 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. PMID:6513765

  9. 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)

  10. 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…

  11. 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…

  12. 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…

  13. 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.

  14. 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.

  15. 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.

  16. 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. PMID:23679733

  17. 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.

  18. Diffusion of monochromatic classical waves.

    PubMed

    Gerritsen, Sijmen; Bauer, Gerrit E W

    2006-01-01

    We study the diffusion of monochromatic classical waves in a disordered acoustic medium by scattering theory. In order to avoid artifacts associated with mathematical point scatterers, we model the randomness by small but finite insertions. We derive expressions for the configuration-averaged energy flux, energy density, and intensity for one-, two-, and three-dimensional (3D) systems with an embedded monochromatic source using the ladder approximation to the Bethe-Salpeter equation. We study the transition from ballistic to diffusive wave propagation and obtain results for the frequency dependence of the medium properties such as mean free path and diffusion coefficient as a function of the scattering parameters. We discover characteristic differences of the diffusion in 2D as compared to the conventional 3D case, such as an explicit dependence of the energy flux on the mean free path and quite different expressions for the effective transport velocity. PMID:16486306

  19. Classical Concepts in Quantum Programming

    NASA Astrophysics Data System (ADS)

    Ömer, Bernhard

    2005-07-01

    The rapid progress of computer technology has been accompanied by a corresponding evolution of software development, from hardwired components and binary machine code to high level programming languages, which allowed to master the increasing hardware complexity and fully exploit its potential. This paper investigates, how classical concepts like hardware abstraction, hierarchical programs, data types, memory management, flow of control, and structured programming can be used in quantum computing. The experimental language QCL will be introduced as an example, how elements like irreversible functions, local variables, and conditional branching, which have no direct quantum counterparts, can be implemented, and how nonclassical features like the reversibility of unitary transformation or the nonobservability of quantum states can be accounted for within the framework of a procedural programming language.

  20. 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

  1. 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. PMID:27147112

  2. Classical catalase: ancient and modern.

    PubMed

    Nicholls, Peter

    2012-09-15

    This review describes the historical difficulties in devising a kinetically satisfactory mechanism for the classical catalase after its identification as a unique catalytic entity in 1902 and prior to the breakthrough 1947 analysis by Chance and co-workers which led to the identification of peroxide compounds I and II. The role of protons in the formation of these two ferryl complexes is discussed and current problems of inhibitory ligand and hydrogen donor binding at the active site are outlined, especially the multiple roles involving formate or formic acid. A previous mechanism of NADPH-dependent catalase protection against substrate inhibition is defended. A revised model linking the catalytic ('catalatic') action and the one-electron side reactions involving compound II is suggested. And it is concluded that, contrary to an idea proposed in 1963 that eukaryotic catalase might be a 'fossil enzyme', current thinking gives it a central role in the redox protective processes of long term importance for human and other eukaryotic and prokaryotic life. PMID:22326823

  3. 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.

  4. Crystallization of classical multicomponent plasmas

    SciTech Connect

    Medin, Zach; Cumming, Andrew

    2010-03-15

    We develop a method for calculating the equilibrium properties of the liquid-solid phase transition in a classical, ideal, multicomponent plasma. Our method is a semianalytic calculation that relies on extending the accurate fitting formulas available for the one-, two-, and three-component plasmas to the case of a plasma with an arbitrary number of components. We compare our results to those of C. J. Horowitz et al. [Phys. Rev. E 75, 066101 (2007)], who used a molecular-dynamics simulation to study the chemical properties of a 17-species mixture relevant to the ocean-crust boundary of an accreting neutron star at the point where half the mixture has solidified. Given the same initial composition as Horowitz et al., we are able to reproduce to good accuracy both the liquid and solid compositions at the half-freezing point; we find abundances for most species within 10% of the simulation values. Our method allows the phase diagram of complex mixtures to be explored more thoroughly than possible with numerical simulations. We briefly discuss the implications for the nature of the liquid-solid boundary in accreting neutron stars.

  5. Olfactory Classical Conditioning in Neonates

    PubMed Central

    Sullivan, Regina M.; Taborsky-Barba, Suzanne; Mendoza, Raffael; Itano, Alison; Leon, Michael; Cotman, Carl W.; Payne, Terrence F.; Lott, Ira

    2007-01-01

    One-day-old, awake infants underwent an olfactory classical conditioning procedure to assess associative learning within the olfactory system of newborns. Experimental infants received ten 30-second pairings of a novel olfactory conditioned stimulus (a citrus odor of neutral value) and tactile stimulation provided by stroking as the reinforcing unconditioned stimulus (a stimulus with positive properties). Control babies received only the odor, only the stroking, or the stroking followed by the odor presentation. The next day, all infants, in either the awake or sleep state, were given five 30-second presentations of the odor. Results were analyzed from video tapes scored by an observer unaware of the infants’ training condition. The results indicate that only those infants who received the forward pairings of the odor and stroking exhibited conditioned responding (head turning toward the odor) to the citrus odor. The performance of the conditioned response was not affected by the state of the baby during testing, because both awake and sleeping infants exhibited conditioned responses. Furthermore, the expression of the conditioned response was odor specific; a novel floral odor presented during testing did not elicit conditioned responses in the experimental babies. These results suggest that complex associative olfactory learning is seen in newborns within the first 48 hours of life. These baseline findings may serve as normative data against which observation from neonates at risk for neurological sequelae may be compared. PMID:2011429

  6. Fragmentation of hot classical drops

    SciTech Connect

    Vicentini, A.; Jacucci, G.; Pandharipande, V.R.

    1985-05-01

    Time evolution of hot drops of matter containing approx.230 or approx.130 particles is studied by classical molecular dynamics. Initially, the drops have uniform density and a sharp surface. The chosen initial conditions include three values of density and a range of temperatures wide enough to study the phenomena of evaporation, fragmentation, and total vaporization in a unified fashion. The average density and temperature of central matter is measured periodically to obtain trajectories of the evolution in the rho,T plane. These trajectories indicate that the matter expands almost adiabatically until it reaches the region of adiabatic instabilities. Density inhomogeneities develop in this region, but the matter fragments only if the expansion continues to average densities of less than one-fourth the liquid density, otherwise it recondenses into a single blob. The recondensed matter and fragments have very crooked surfaces. If the temperature is high enough, the expanding matter does not enter the region of adiabatic instabilities and totally vaporizes. For initial densities of the order of equilibrium density, matter does not fragment or develop large inhomogeneities in the region enclosed by the isothermal and adiabatic spinodals. Thus it appears unlikely that fragmentation of small drops (nuclei) can be used to study the isothermal critical region of gas-liquid phase transition. A detailed tabulation of the energies and number of monomers, dimers, light, and heavy fragments emitted in each event is presented.

  7. Classical universes are perfectly predictable!

    NASA Astrophysics Data System (ADS)

    Schmidt, Jan Hendrik

    I argue that in a classical universe, all the events that ever happen are encoded in each of the universe's parts. This conflicts with a statement which is widely believed to lie at the basis of relativity theory: that the events in a space-time region R determine only the events in R's domain of dependence but not those in other space-time regions. I show how, from this understanding, a new prediction method (which I call the 'Smoothness Method') can be obtained which allows us to predict future events on the basis of local observational data. Like traditional prediction methods, this method makes use of so-called ' ceteris paribus clauses', i.e. assumptions about the unobserved parts of the universe. However, these assumptions are used in a way which enables us to predict the behaviour of open systems with arbitrary accuracy, regardless of the influence of their environment-which has not been achieved by traditional methods. In a sequel to this paper (Schmidt, 1998), I will prove the Uniqueness and Predictability Theorems on which the Smoothness Method is based, and comment in more detail on its mathematical properties.

  8. Potential wells for classical acoustic waves

    NASA Astrophysics Data System (ADS)

    Chen, Shi; Lin, ShuYu; Mo, RunYang; Fu, ZhiQiang

    2014-01-01

    The acceleration theorem of Bloch waves is utilized to construct random potential wells for classical acoustic waves in systems composed of alternating `cavities' and `couplers'. One prominent advantage of this method is these `cavities' and `couplers' are all monolayer structures. It allows forming more compact classical potential wells, which leads to the miniaturization of acoustic devices. We systematically investigate properties of harmonic, tangent, hyperbolic function, and square classical potential wells in quasi-periodic superlattices. Results show these classical potential wells are analogues of quantum potential wells. Thus some technologies and concepts in quantum potential well fields may be generalized to classical acoustic wave fields. In addition, some abnormal cases regarding forming classical potential wells are also found.

  9. 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.

  10. 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}

  11. On the tomographic description of classical fields

    NASA Astrophysics Data System (ADS)

    Ibort, A.; López-Yela, A.; Man'ko, V. I.; Marmo, G.; Simoni, A.; Sudarshan, E. C. G.; Ventriglia, F.

    2012-03-01

    After a general description of the tomographic picture for classical systems, a tomographic description of free classical scalar fields is proposed both in a finite cavity and the continuum. The tomographic description is constructed in analogy with the classical tomographic picture of an ensemble of harmonic oscillators. The tomograms of a number of relevant states such as the canonical distribution, the classical counterpart of quantum coherent states and a new family of so-called Gauss-Laguerre states, are discussed. Finally the Liouville equation for field states is described in the tomographic picture offering an alternative description of the dynamics of the system that can be extended naturally to other fields.

  12. 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)

  13. Primary Mediastinal Classical Hodgkin Lymphoma.

    PubMed

    Piña-Oviedo, Sergio; Moran, Cesar A

    2016-09-01

    Primary mediastinal Classical Hodgkin lymphoma (CHL) is rare. Nodular sclerosis CHL (NS-CHL) is the most common subtype involving the anterior mediastinum and/or mediastinal lymph nodes. Primary thymic CHL is exceedingly rare. The disease typically affects young women and is asymptomatic in 30% to 50% of patients. Common symptoms include fatigue, chest pain, dyspnea and cough, but vary depending on the location and size of the tumor. B-symptoms develop in 30% of cases. By imaging, primary mediastinal CHL presents as mediastinal widening/mediastinal mass that does not invade adjacent organs but may compress vital structures as bulky disease. Histopathology is the gold standard for diagnosis. Primary mediastinal NS-CHL consists of nodules of polymorphous inflammatory cells surrounded by broad fibrous bands extending from a thickened lymph node capsule. The cellular nodules contain variable numbers of large Hodgkin/Reed-Sternberg cells, required for diagnosis. Primary thymic CHL may exhibit prominent cystic changes. The histopathologic recognition of NS-CHL can be challenging in cases with prominent fibrosis, scant cellularity, artifactual cell distortion, or an exuberant granulomatous reaction. The differential diagnosis includes primary mediastinal non-HLs, mediastinal germ cell tumors, thymoma, and metastatic carcinoma or melanoma to the mediastinum. Distinction from primary mediastinal non-HLs is crucial for adequate therapeutic decisions. Approximately 95% of patients with primary mediastinal CHL will be alive and free of disease at 10 years after treatment with short courses of combined chemoradiotherapy. In this review, we discuss the history, classification, epidemiology, clinicoradiologic features, histopathology, immunohistochemistry, differential diagnosis, and treatment of primary mediastinal CHL. PMID:27441757

  14. 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)

  15. 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).

  16. Element abundances of classical novae

    NASA Astrophysics Data System (ADS)

    Andrea, J.; Drechsel, H.; Starrfield, S.

    1994-11-01

    Physical conditions and element abundances in the optically thin shells of 11 classical novae with outbursts between 1978 and 1989 were determined from an analysis of UV and optical spectra obtained during the nebular stage. Eight novae were studied on the basis of new optical and UV spectra. The accuracy of the element abundances depends on whether or not simultaneous UV spectra were available to determine individual ionization stage dependent gas temperatures. Generally, slightly higher than solar abundances of helium and pronounced overabundances of the heavier elements were found. QU Vul turned out to be an ONeMg nova, while the other objects belong to the class of CO novae. The nature of V2214 Oph could not be completely clarified. The novae V1668 Cyg (1978), V693 CrA (1981), and V1370 Aql (1982), for which published element abundances exist, were reanalyzed to check the consistency of our spectral analysis approach. Satisfactory agreement of the results was found. Photoionization calculations were carried out for PW Vul using the code of Aldrovandi, Pequignot, and Stasinska. A synthetic spectrum was generated for the parameters derived from the analysis of the UV and optical spectra, which is in very good agreement with the observations. The spectral analysis technique was then applied to the model spectrum and reproduced the model parameters well. Electron temperatures for the C(2+) and C(3+) ions between 7 500 and 12,000 K and for N(4+) betwen 12,000 and 16,000 K were derived. For PW Vul these temperatures remained relatively constant over several months. The decline in density of the ejected shells with time could be investigated for V842 Cen, QV Vul, V977 Sco, and V443 Sct, and was found to deviate from the relation Ne proportional to t-2 for free expansion of a shell in a different way for each object. A possible explanation may be the complex density structure of the shells. This suspicion is supported by high resolution spectra (ESO 3.6m telescope

  17. 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

  18. 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…

  19. 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 process,…

  20. 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…

  1. Three approaches to classical thermal field theory

    NASA Astrophysics Data System (ADS)

    Gozzi, E.; Penco, R.

    2011-04-01

    In this paper we study three different functional approaches to classical thermal field theory, which turn out to be the classical counterparts of three well-known different formulations of quantum thermal field theory: the closed-time path (CTP) formalism, the thermofield dynamics (TFD) and the Matsubara approach.

  2. 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.…

  3. Modal analysis of a classical guitar

    NASA Astrophysics Data System (ADS)

    Cohen, David; Rossing, Thomas D.

    2002-11-01

    Using holographic interferometry, we have determined the modes of vibration of a classical guitar (by the first author) having an asymmetrically-braced top plate and a crossed braced back of unique design. The vibrational modes and acoustical properties are compared with other classical guitars.

  4. 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…

  5. The Dance of Spain: Classical Folkloric Flamenco.

    ERIC Educational Resources Information Center

    Gallant, Clifford J.

    A text on the classical and folk dance of Spain includes a pretest, provided in both English and Spanish; text about the dance in general and the dance of Spain, both classical and folkloric; tests on the text, in both English and Spanish; more specific readings about the traditions of flamenco, castanets, and "el jaleo"; a glossary of flamenco…

  6. Classics and Moral Education: A Reply

    ERIC Educational Resources Information Center

    White, Pat

    1975-01-01

    Criticizes John Wilson's "Classics and Moral Education," in this issue, as being ambiguous and vague. The view here is that moral education would not derive automatically from classical studies but must be taught and developed, and based on a value system already present. (CHK)

  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. Classic and Hard-Boiled Detective Fiction.

    ERIC Educational Resources Information Center

    Reilly, John M.

    Through an analysis of several stories, this paper defines the similarities and differences between classic and hard-boiled detective fiction. The characters and plots of three stories are discussed: "The Red House" by A. A. Milne; "I, The Jury" by Mickey Spillane; and "League of Frightened Men" by Rex Stout. The classic detective story is defined…

  9. 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.

  10. 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…

  11. 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 decline so grave as to prompt a…

  12. Classical decoherence in a nanomechanical resonator

    NASA Astrophysics Data System (ADS)

    Maillet, O.; Vavrek, F.; Fefferman, A. D.; Bourgeois, O.; Collin, E.

    2016-07-01

    Decoherence is an essential mechanism that defines the boundary between classical and quantum behaviours, while imposing technological bounds for quantum devices. Little is known about quantum coherence of mechanical systems, as opposed to electromagnetic degrees of freedom. But decoherence can also be thought of in a purely classical context, as the loss of phase coherence in the classical phase space. Indeed the bridge between quantum and classical physics is under intense investigation, using, in particular, classical nanomechanical analogues of quantum phenomena. In the present work, by separating pure dephasing from dissipation, we quantitatively model the classical decoherence of a mechanical resonator: through the experimental control of frequency fluctuations, we engineer artificial dephasing. Building on the fruitful analogy introduced between spins/quantum bits and nanomechanical modes, we report on the methods available to define pure dephasing in these systems, while demonstrating the intrinsic almost-ideal properties of silicon nitride beams. These experimental and theoretical results, at the boundary between classical nanomechanics and quantum information fields, are prerequisite in the understanding of decoherence processes in mechanical devices, both classical and quantum.

  13. Classical data compression with quantum side information

    SciTech Connect

    Devetak, I.; Winter, A.

    2003-10-01

    The problem of classical data compression when the decoder has quantum side information at his disposal is considered. This is a quantum generalization of the classical Slepian-Wolf theorem. The optimal compression rate is found to be reduced from the Shannon entropy of the source by the Holevo information between the source and side information.

  14. 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…

  15. On entanglement-assisted classical capacity

    NASA Astrophysics Data System (ADS)

    Holevo, A. S.

    2002-09-01

    We give a modified proof of the recent result of C. H. Bennett, P. W. Shor, J. A. Smolin, and A. V. Thapliyal concerning entanglement-assisted classical capacity of a quantum channel and discuss the relation between entanglement-assisted and unassisted classical capacities.

  16. Recent developments in classical density modification

    PubMed Central

    Cowtan, Kevin

    2010-01-01

    Classical density-modification techniques (as opposed to statistical approaches) offer a computationally cheap method for improving phase estimates in order to provide a good electron-density map for model building. The rise of statistical methods has lead to a shift in focus away from the classical approaches; as a result, some recent developments have not made their way into classical density-modification software. This paper describes the application of some recent tech­niques, including most importantly the use of prior phase information in the likelihood estimation of phase errors within a classical density-modification framework. The resulting software gives significantly better results than comparable classical methods, while remaining nearly two orders of magnitude faster than statistical methods. PMID:20383000

  17. Classical and quantum correlations under decoherence

    SciTech Connect

    Maziero, J.; Celeri, L. C.; Serra, R. M.; Vedral, V.

    2009-10-15

    Recently some authors have pointed out that there exist nonclassical correlations which are more general, and possibly more fundamental, than entanglement. For these general quantum correlations and their classical counterparts, under the action of decoherence, we identify three general types of dynamics that include a peculiar sudden change in their decay rates. We show that, under suitable conditions, the classical correlation is unaffected by decoherence. Such dynamic behavior suggests an operational measure of both classical and quantum correlations that can be computed without any extremization procedur000.

  18. Classical odderon in QCD at high energies

    SciTech Connect

    Jeon, Sangyong; Venugopalan, Raju

    2005-06-15

    We show that the weight functional for color sources in the classical theory of the color glass condensate (CGC) includes a term which generates odderon excitations. Remarkably, the classical origin of these excitations can be traced to the random walk of partons in the two dimensional space spanned by the SU(3) Casimirs. We compute dipole and baryon odderon operators in the CGC and show that contributions from the classical color sources to these are suppressed in the limit of very large parton densities.

  19. Applying classical geometry intuition to quantum spin

    NASA Astrophysics Data System (ADS)

    Durfee, Dallin S.; Archibald, James L.

    2016-09-01

    Using concepts of geometric orthogonality and linear independence, we logically deduce the form of the Pauli spin matrices and the relationships between the three spatially orthogonal basis sets of the spin-1/2 system. Rather than a mathematically rigorous derivation, the relationships are found by forcing expectation values of the different basis states to have the properties we expect of a classical, geometric coordinate system. The process highlights the correspondence of quantum angular momentum with classical notions of geometric orthogonality, even for the inherently non-classical spin-1/2 system. In the process, differences in and connections between geometrical space and Hilbert space are illustrated.

  20. 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.

  1. Nonconservation of momentum in classical mechanics

    NASA Astrophysics Data System (ADS)

    Lee, Chunghyoung

    Pérez Laraudogoitia (1996) presented an isolated system of infinitely many particles with infinite total mass whose total classical energy and momentum are not necessarily conserved in some particular inertial frame of reference. With a more generalized model Atkinson (2007) proved that a system of infinitely many balls with finite total mass may evolve so that its total classical energy and total relativistic energy and momentum are not conserved in any inertial frame of reference, and yet concluded that its total classical momentum is necessarily conserved. Contrary to this conclusion of Atkinson, I show that Atkinson's model has a solution in which the total momentum fails to be conserved in every inertial frame of reference. This result, combined with Atkinson's, demonstrates that both classical and relativistic mechanics allow the energy and momentum of a system of infinitely many components to fail to be conserved in every inertial frame of reference.

  2. Entropic inequalities in classical and quantum domains

    NASA Astrophysics Data System (ADS)

    Man'ko, Margarita A.

    2010-09-01

    Different kinds of entropy associated with probability distribution functions characterizing the system state in classical and quantum domains are reviewed. Shannon entropy and Rényi entropy are discussed. The notion of tomographic entropy determined by the probability distribution in the phase space of the classical system and by the density operator of the quantum system is considered. Inequalities for the tomographic entropies in classical and quantum domains are studied, and a difference in the form of these inequalities in corresponding domains is suggested as a test to clarify the classicality and quantumness of the system state in quantum optics experiments. A new bound for tomographic entropy (ln πe)Φ(θ) depending on the local oscillator phase difference in homodyne photon detection experiments is discussed.

  3. 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)

  4. Non-classical divalent lanthanide complexes.

    PubMed

    Nief, François

    2010-08-01

    The synthesis of non-classical divalent lanthanide complexes, i.e. those not containing the classical samarium(II), europium(II) or ytterbium(II), was once thought impossible. Since 1997, when the first stable complex of thulium(II) was discovered, there has been many more examples of stable coordination and organometallic complexes of lanthanum(II), neodymium(II) and dysprosium(II) in addition to thulium(II), and the influence of the ligand system on the stability of the complexes is beginning to be understood. These non-classical divalent compounds show exceptional reactivity as some of them have been shown to activate dinitrogen at room temperature, together with related reduced divalent-like systems, and to undergo spontaneous intramolecular carbon-hydrogen bond activation. Many more examples of non-classical divalent compounds together with new aspects of their exciting reactivity should be discovered in the near future. PMID:20631944

  5. Secure quantum communication using classical correlated channel

    NASA Astrophysics Data System (ADS)

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

    2016-07-01

    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.

  6. 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)

  7. Hermite polynomials and quasi-classical asymptotics

    SciTech Connect

    Ali, S. Twareque; Engliš, Miroslav

    2014-04-15

    We study an unorthodox variant of the Berezin-Toeplitz type of quantization scheme, on a reproducing kernel Hilbert space generated by the real Hermite polynomials and work out the associated quasi-classical asymptotics.

  8. 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.

  9. Racing in parallel: Quantum versus Classical

    NASA Astrophysics Data System (ADS)

    Steiger, Damian S.; Troyer, Matthias

    In a fair comparison of the performance of a quantum algorithm to a classical one it is important to treat them on equal footing, both regarding resource usage and parallelism. We show how one may otherwise mistakenly attribute speedup due to parallelism as quantum speedup. We apply such an analysis both to analog quantum devices (quantum annealers) and gate model algorithms and give several examples where a careful analysis of parallelism makes a significant difference in the comparison between classical and quantum algorithms.

  10. Classical gravity does not refract negatively.

    PubMed

    McCall, Martin W

    2007-03-01

    We appraise recent claims that classical gravitation can induce negative refraction of electromagnetic radiation in vacuum. By recasting the previous literature in covariant notation, we show that the criterion used hitherto for determining negative refraction in vacuum is inappropriate, and can even be satisfied by parametrized transformations in Minkowski spacetime. Using instead a covariantly acceptable definition, we find that in classical vacuum the power flux of a plane electromagnetic wave points in the direction of phase advance. PMID:17359145

  11. Instability in the Classic Theory of Coarsening

    NASA Astrophysics Data System (ADS)

    Karpov, V. G.

    1995-04-01

    It is shown that classic coarsening theory is unstable with respect to large-scale fluctuations of the linear dimension considerably exceeding the average intergrain distance and amplitudes of the order of the average values of the corresponding quantities. The consideration is based on reducing the classic theory equations to the form allowing the standard Fourier analysis to be employed. In the case of mobile nuclei, the tendency toward instability is shown to increase.

  12. Bohmian mechanics and the emergence of classicality

    NASA Astrophysics Data System (ADS)

    Matzkin, A.

    2009-06-01

    Bohmian mechanics is endowed with an ontological package that supposedly allows to solve the main interpretational problems of quantum mechanics. We are concerned in this work by the emergence of classicality from the quantum mechanical substrate. We will argue that although being superficially attractive, the de Broglie-Bohm interpretation does not shed new light on the quantum-to-classical transition. This is due to nature of the dynamical law of Bohmian mechanics by which the particles follow the streamlines of the probability flow. As a consequence, Bohmian trajectories can be highly non-classical even when the wavefunction propagates along classical trajectories, as happens in semiclassical systems. In order to account for classical dynamics, Bohmian mechanics needs non-spreading and non-interfering wave packets: this is achieved for practical purposes by having recourse to decoherence and dense measurements. However one then faces the usual fundamental problems associated with the meaning of reduced density matrices. Moreover the specific assets of the de Broglie-Bohm interpretation - in particular the existence of point-like particles pursuing well-defined trajectories - would play no role in accounting for the emergence of classical dynamics.

  13. 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.

  14. An action for a classical string, the equation of motion and group invariant classical solutions

    NASA Astrophysics Data System (ADS)

    Bracken, Paul

    2008-09-01

    A string action which is essentially a Willmore functional is presented and studied. This action determines the physics of a surface in Euclidean three space which can be used to model classical string configurations. By varying this action an equation of motion for the mean curvature of the surface is obtained which is shown to govern certain classical string configurations. Several classes of classical solutions for this equation are discussed from the symmetry group point of view and an application is presented.

  15. Non-classical protein secretion in bacteria

    PubMed Central

    Bendtsen, Jannick D; Kiemer, Lars; Fausbøll, Anders; Brunak, Søren

    2005-01-01

    Background We present an overview of bacterial non-classical secretion and a prediction method for identification of proteins following signal peptide independent secretion pathways. We have compiled a list of proteins found extracellularly despite the absence of a signal peptide. Some of these proteins also have known roles in the cytoplasm, which means they could be so-called "moon-lightning" proteins having more than one function. Results A thorough literature search was conducted to compile a list of currently known bacterial non-classically secreted proteins. Pattern finding methods were applied to the sequences in order to identify putative signal sequences or motifs responsible for their secretion. We have found no signal or motif characteristic to any majority of the proteins in the compiled list of non-classically secreted proteins, and conclude that these proteins, indeed, seem to be secreted in a novel fashion. However, we also show that the apparently non-classically secreted proteins are still distinguished from cellular proteins by properties such as amino acid composition, secondary structure and disordered regions. Specifically, prediction of disorder reveals that bacterial secretory proteins are more structurally disordered than their cytoplasmic counterparts. Finally, artificial neural networks were used to construct protein feature based methods for identification of non-classically secreted proteins in both Gram-positive and Gram-negative bacteria. Conclusion We present a publicly available prediction method capable of discriminating between this group of proteins and other proteins, thus allowing for the identification of novel non-classically secreted proteins. We suggest candidates for non-classically secreted proteins in Escherichia coli and Bacillus subtilis. The prediction method is available online. PMID:16212653

  16. Classical Theory, Postmodernism, and the Sociology Liberal Arts Curriculum.

    ERIC Educational Resources Information Center

    Lembcke, Jerry Lee

    1993-01-01

    Discusses classical theory as a modernist endeavor to apprehend the phenomenon of "unity of disunity." Presents three ways that classical theory approaches the philosophy views of Durkheim, Marx, and Weber. Concludes that postmodernism validates the relevancy of classical theory. (CFR)

  17. Trading Classical and Quantum Computational Resources

    NASA Astrophysics Data System (ADS)

    Bravyi, Sergey; Smith, Graeme; Smolin, John A.

    2016-04-01

    We propose examples of a hybrid quantum-classical simulation where a classical computer assisted by a small quantum processor can efficiently simulate a larger quantum system. First, we consider sparse quantum circuits such that each qubit participates in O (1 ) two-qubit gates. It is shown that any sparse circuit on n +k qubits can be simulated by sparse circuits on n qubits and a classical processing that takes time 2O (k )poly (n ) . Second, we study Pauli-based computation (PBC), where allowed operations are nondestructive eigenvalue measurements of n -qubit Pauli operators. The computation begins by initializing each qubit in the so-called magic state. This model is known to be equivalent to the universal quantum computer. We show that any PBC on n +k qubits can be simulated by PBCs on n qubits and a classical processing that takes time 2O (k )poly (n ). Finally, we propose a purely classical algorithm that can simulate a PBC on n qubits in a time 2α npoly (n ) , where α ≈0.94 . This improves upon the brute-force simulation method, which takes time 2npoly (n ). Our algorithm exploits the fact that n -fold tensor products of magic states admit a low-rank decomposition into n -qubit stabilizer states.

  18. 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.

  19. Unraveling Quantum Annealers using Classical Hardness.

    PubMed

    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

  20. 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. PMID:20357767

  1. 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.

  2. Relativistic Entanglement From Maxwell's Classical Equations

    NASA Astrophysics Data System (ADS)

    Carroll, John E.; Quarterman, Adrian H.

    2013-09-01

    With the help of light cone coordinates and light cone field representations of Maxwell's classical equations, quantum polarization entanglement is explained using the relativistic results of a companion paper that shows how conventional or reference waves can have an adjoint wave, travelling in phase with the reference wave, but in a proper relativistic frame that travels in the opposing direction to the proper frame of the reference wave. This subsequently allows waves, travelling in opposite directions, to have the same proper frame and consequently such waves can be regarded as relativistically local. The light cone coordinates offer a classical form of a quantum wave function and demonstrate a classical equivalent of a mixed quantum state.

  3. Classical antiferromagnet on a hyperkagome lattice.

    PubMed

    Hopkinson, John M; Isakov, Sergei V; Kee, Hae-Young; Kim, Yong Baek

    2007-07-20

    Motivated by recent experiments on Na4Ir3O8 [Y. Okamoto, M. Nohara, H. Aruga-Katori, and H. Takagi, arXiv:0705.2821 (unpublished)], we study the classical antiferromagnet on a frustrated three-dimensional lattice obtained by selectively removing one of four sites in each tetrahedron of the pyrochlore lattice. This "hyperkagome" lattice consists of corner-sharing triangles. We present the results of large-N mean field theory and Monte Carlo computations on O(N) classical spin models. It is found that the classical ground states are highly degenerate. Nonetheless a nematic order emerges at low temperatures in the Heisenberg model (N=3) via "order by disorder," representing the dominance of coplanar spin configurations. Implications for ongoing experiments are discussed. PMID:17678320

  4. Quantum dynamics simulation with classical oscillators

    NASA Astrophysics Data System (ADS)

    Briggs, John S.; Eisfeld, Alexander

    2013-12-01

    In a previous paper [J. S. Briggs and A. Eisfeld, Phys. Rev. APLRAAN1050-294710.1103/PhysRevA.85.052111 85, 052111 (2012)] we showed that the time development of the complex amplitudes of N coupled quantum states can be mapped by the time development of positions and velocities of N coupled classical oscillators. Here we examine to what extent this mapping can be realized to simulate the “quantum,” properties of entanglement and qubit manipulation. By working through specific examples, e.g., of quantum gate operation, we seek to illuminate quantum and classical differences which hitherto have been treated more mathematically. In addition, we show that important quantum coupled phenomena, such as the Landau-Zener transition and the occurrence of Fano resonances can be simulated by classical oscillators.

  5. 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

  6. Classical analogs of double electromagnetically induced transparency

    NASA Astrophysics Data System (ADS)

    Bai, Zhengyang; Hang, Chao; Huang, Guoxiang

    2013-03-01

    Double electromagnetically induced transparency (DEIT) in a four-level atomic system with tripod-type energy-level configuration is modeled by using two classical systems. The first is a set of three coupled harmonic oscillators subject to frictional forces and external drives and the second is a set of three coupled RLC circuits with electric resistors and alternating voltage sources. It is shown that both of the two classical systems have absorption spectra of DEIT similar to that of the four-level tripod-type atomic system. These classical analogies provide simple and intuitive physical description of quantum interference processes and can be used to illustrate experimental observations of the DEIT in quantum systems.

  7. Manifestly diffeomorphism invariant classical Exact Renormalization Group

    NASA Astrophysics Data System (ADS)

    Morris, Tim R.; Preston, Anthony W. H.

    2016-06-01

    We construct a manifestly diffeomorphism invariant Wilsonian (Exact) Renor-malization Group for classical gravity, and begin the construction for quantum gravity. We demonstrate that the effective action can be computed without gauge fixing the diffeo-morphism invariance, and also without introducing a background space-time. We compute classical contributions both within a background-independent framework and by perturbing around a fixed background, and verify that the results are equivalent. We derive the exact Ward identities for actions and kernels and verify consistency. We formulate two forms of the flow equation corresponding to the two choices of classical fixed-point: the Gaussian fixed point, and the scale invariant interacting fixed point using curvature-squared terms. We suggest how this programme may completed to a fully quantum construction.

  8. Classical Approach to Multichromophoric Resonance Energy Transfer

    NASA Astrophysics Data System (ADS)

    Duque, Sebastián; Brumer, Paul; Pachón, Leonardo A.

    2015-09-01

    A classical formulation of the quantum multichromophoric theory of resonance energy transfer is developed on the basis of classical electrodynamics. The theory allows for the identification of a variety of processes of different order in the interactions that contribute to the energy transfer in molecular aggregates with intracoupling in donors and acceptor chromophores. Enhanced rates in multichromophoric resonance energy transfer are shown to be well described by this theory. Specifically, in a coupling configuration between NA acceptors and ND donors, the theory correctly predicts an enhancement of the energy transfer rate dependent on the total number of donor-acceptor pairs. As an example, the theory, applied to the transfer rate in light harvesting II, gives results in excellent agreement with experiment. Finally, it is explicitly shown that as long as linear response theory holds, the classical multichromophoric theory formally coincides with the quantum formulation.

  9. Non-Classical Inhibition of Carbonic Anhydrase.

    PubMed

    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

  10. Coexistence of peptides with classical neurotransmitters.

    PubMed

    Hökfelt, T; Millhorn, D; Seroogy, K; Tsuruo, Y; Ceccatelli, S; Lindh, B; Meister, B; Melander, T; Schalling, M; Bartfai, T

    1987-07-15

    In the present article the fact is emphasized that neuropeptides often are located in the same neurons as classical transmitters such as acetylcholine, 5-hydroxy-tryptamine, catecholamines, gamma-aminobutyric acid (GABA) etc. This raises the possibility that neurons produce, store and release more than one messenger molecule. The exact functional role of such coexisting peptides is often difficult to evaluate, especially in the central nervous system. In the periphery some studies indicate apparently meaningful interactions of different types with the classical transmitter, but other types of actions including trophic effects have been observed. More recently it has been shown that some neurons contain more than one classical transmitter, e.g. 5-HT plus GABA, further underlining the view that transfer of information across synapses may be more complex than perhaps hitherto assumed. PMID:2885215

  11. Classical approach to multichromophoric resonance energy transfer.

    PubMed

    Duque, Sebastián; Brumer, Paul; Pachón, Leonardo A

    2015-09-11

    A classical formulation of the quantum multichromophoric theory of resonance energy transfer is developed on the basis of classical electrodynamics. The theory allows for the identification of a variety of processes of different order in the interactions that contribute to the energy transfer in molecular aggregates with intracoupling in donors and acceptor chromophores. Enhanced rates in multichromophoric resonance energy transfer are shown to be well described by this theory. Specifically, in a coupling configuration between N_{A} acceptors and N_{D} donors, the theory correctly predicts an enhancement of the energy transfer rate dependent on the total number of donor-acceptor pairs. As an example, the theory, applied to the transfer rate in light harvesting II, gives results in excellent agreement with experiment. Finally, it is explicitly shown that as long as linear response theory holds, the classical multichromophoric theory formally coincides with the quantum formulation. PMID:26406811

  12. 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.

  13. Observable signatures of a classical transition

    NASA Astrophysics Data System (ADS)

    Johnson, Matthew C.; Lin, Wei

    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.

  14. 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.

  15. Classical dynamics on curved Snyder space

    NASA Astrophysics Data System (ADS)

    Ivetić, B.; Meljanac, S.; Mignemi, S.

    2014-05-01

    We study the classical dynamics of a particle in nonrelativistic Snyder-de Sitter space. We show that for spherically symmetric systems, parameterizing the solutions in terms of an auxiliary time variable, which is a function only of the physical time and of the energy and angular momentum of the particles, one can reduce the problem to the equivalent one in classical mechanics. We also discuss a relativistic extension of these results, and a generalization to the case in which the algebra is realized in flat space.

  16. Relaxation properties of weakly coupled classical systems

    SciTech Connect

    Romero-Rochin, V.; Oppenheim, I.

    1988-10-01

    The relaxation properties of a small classical system weakly coupled to a large classical system which acts as a heat bath are described using a generalized Fokker-Planck equation. The Fokker-Planck equation is derived in general using a modification of the elimination of fast variables techniques previously described. The specific example in which the small system is a harmonic oscillator linearly coupled to the heat bath is treated in detail and it is demonstrated that there is a dynamic frequency shift as well as a statistical shift of the oscillator frequency.

  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 communication cost of quantum steering

    NASA Astrophysics Data System (ADS)

    Sainz, Ana Belén; Aolita, Leandro; Brunner, Nicolas; Gallego, Rodrigo; Skrzypczyk, Paul

    2016-07-01

    Quantum steering is observed when performing appropriate local measurements on an entangled state. Here we discuss the possibility of simulating classically this effect, using classical communication instead of entanglement. We show that infinite communication is necessary for exactly simulating steering for any pure entangled state, as well as for a class of mixed entangled states. Moreover, we discuss the communication cost of steering for general entangled states, as well as approximate simulation. Our findings reveal striking differences between Bell nonlocality and steering and provide a natural way of measuring the strength of the latter.

  19. Chaos in classical D0-brane mechanics

    NASA Astrophysics Data System (ADS)

    Gur-Ari, Guy; Hanada, Masanori; Shenker, Stephen H.

    2016-02-01

    We study chaos in the classical limit of the matrix quantum mechanical system describing D0-brane dynamics. We determine a precise value of the largest Lyapunov exponent, and, with less precision, calculate the entire spectrum of Lyapunov exponents. We verify that these approach a smooth limit as N → ∞. We show that a classical analog of scrambling occurs with fast scrambling scaling, t ∗ ˜ log S. These results confirm the k-locality property of matrix mechanics discussed by Sekino and Susskind.

  20. Enhancing non-classicality in mechanical systems

    NASA Astrophysics Data System (ADS)

    Li, Jie; Gröblacher, Simon; Paternostro, Mauro

    2013-03-01

    We study the effects of post-selection measurements on both the non-classicality of the state of a mechanical oscillator and the entanglement between two mechanical systems that are part of a distributed optomechanical network. We address the cases of both Gaussian and non-Gaussian measurements, identifying in which cases simple photon counting and Geiger-like measurements are effective in distilling a strongly non-classical mechanical state and enhancing the purely mechanical entanglement between two elements of the network.

  1. Galilei relativity principle in classical electrodynamics

    NASA Astrophysics Data System (ADS)

    Kotelnikov, G. A.

    A theorem is formulated that Galilei group is that of Maxwell equation exact symmetry group, providing the fields are transformed by nonlinear representation of this group. Galilei symmetry differs from the relativistic one in the fact that relativistic symmetry is manifested while postulating the light velocity invariance, whereas Galilei symmetry is manifested during postulating time invariance. In relativistic case the field transformations are linear and global, in Galilei case they are nonlinear and evidently depend on time and coordinates. Existence of Galilei symmetry for Maxwell equations means that in a certain sense, Galilei relativity principle holds not only in classical mechanics but in classical electrodynamics too.

  2. Thermodynamic integration from classical to quantum mechanics

    SciTech Connect

    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.

  3. 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.

  4. The molecular mechanisms of classic Hodgkin's lymphoma.

    PubMed Central

    Felberbaum, Rachael S.

    2005-01-01

    Classic Hodgkin's lymphoma is characterized by the appearance of giant abnormal cells called Hodgkin and Reed-Sternberg (HRS) cells. HRS cells arise from germinal center B lymphocytes and in about 50 percent of patients, are infected with Epstein-Barr Virus. In addition, HRS cells show constitutive NF-kappaB activation and are resistant to apoptosis. This paper reviews several recent studies that for the first time implicate specific molecules in the pathogenesis of classic Hodgkin's lymphoma. Targeting these molecules could lead to the development of novel therapies for this disease. PMID:16720015

  5. 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.

  6. Decoherence, chaos, the quantum and the classical

    NASA Astrophysics Data System (ADS)

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

    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.

  7. Classical combustion diagnostics for engine research

    SciTech Connect

    Amann, C.A.

    1985-01-01

    The use of engine diagnostic techniques in research on the reciprocating internal combustion engine has contributed substantially to engine progress over the years. Many of these techniques were developed before the advent of the laser, and most engine research still uses these classical methods. This paper provides historical snapshots of efforts to understand flame propagation and knock in homogeneous-charge engines, and fuel-air mixing and some of its ramifications in diesels. Such a review demonstrates the accomplishments facilitated by measurement of pressure, temperature, fluid motions, and chemistry within the cylinder. A critique of these classical diagnostics is then offered.

  8. 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.

  9. Classical probabilities for Majorana and Weyl spinors

    SciTech Connect

    Wetterich, C.

    2011-08-15

    Highlights: > Map of classical statistical Ising model to fermionic quantum field theory. > Lattice-regularized real Grassmann functional integral for single Weyl spinor. > Emerging complex structure characteristic for quantum physics. > A classical statistical ensemble describes a quantum theory. - Abstract: We construct a map between the quantum field theory of free Weyl or Majorana fermions and the probability distribution of a classical statistical ensemble for Ising spins or discrete bits. More precisely, a Grassmann functional integral based on a real Grassmann algebra specifies the time evolution of the real wave function q{sub {tau}}(t) for the Ising states {tau}. The time dependent probability distribution of a generalized Ising model obtains as p{sub {tau}}(t)=q{sub {tau}}{sup 2}(t). The functional integral employs a lattice regularization for single Weyl or Majorana spinors. We further introduce the complex structure characteristic for quantum mechanics. Probability distributions of the Ising model which correspond to one or many propagating fermions are discussed explicitly. Expectation values of observables can be computed equivalently in the classical statistical Ising model or in the quantum field theory for fermions.

  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. Ethnicity and Classicism: A Beautiful Connection.

    ERIC Educational Resources Information Center

    Mitchell, Arthur

    1984-01-01

    The founder of the Dance Theater of Harlem describes his own professional development and discusses how Martin Luther King's assassination led him to make a commitment to the people of Harlem, to the untapped talents of Black artists, and to breaking the traditional barrier against Black dancers in classical ballet. (CMG)

  12. 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)

  13. 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,…

  14. 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

    2013-01-01

    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. PMID:23866841

  15. Fertility preservation in female classic galactosemia patients

    PubMed Central

    2013-01-01

    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. PMID:23866841

  16. 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)

  17. 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…

  18. 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…

  19. Classical Linguistics in the United States.

    ERIC Educational Resources Information Center

    Poultney, James W.

    1988-01-01

    Reviews the history of classical linguistic studies in the United States. Cites many of the important American classicists from the nineteenth century to the present. Also gives the history of some scholarly organizations, including the Linguistic Society of America and the American Philological Association. (LMO)

  20. 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

  1. 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…

  2. Classical "Topoi" and the Academic Commonplace.

    ERIC Educational Resources Information Center

    Musgrove, Laurence E.

    An investigation of the various ways the term "topos" is used in classical rhetoric reveals the limited range of invention strategies offered by academic discourse pedagogy. Donald Bartholmae's work on basic writing addresses the relationship of the commonplace to topical invention within academic discourse. Investigation of the history of…

  3. Classical and quantum Kummer shape algebras

    NASA Astrophysics Data System (ADS)

    Odzijewicz, A.; Wawreniuk, E.

    2016-07-01

    We study a family of integrable systems of nonlinearly coupled harmonic oscillators on the classical and quantum levels. We show that the integrability of these systems follows from their symmetry characterized by algebras, here called Kummer shape algebras. The resolution of identity for a wide class of reproducing kernels is found. A number of examples, illustrating this theory, are also presented.

  4. The Classical Diffusion Paradigm in Crisis.

    ERIC Educational Resources Information Center

    Hooks, Gregory

    The erosion of the credibility of the classical diffusion paradigm by recent challenges to its fundamental assumptions has resulted in a "paradigmatic crisis" as related to research on the diffusion of agricultural innovations. Such basic assumptions as that of a harmonious and cooperative society and of agricultural research guided by endogenous…

  5. 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…

  6. Multiple-Access Quantum-Classical Networks

    NASA Astrophysics Data System (ADS)

    Razavi, Mohsen

    2011-10-01

    A multi-user network that supports both classical and quantum communication is proposed. By relying on optical code-division multiple access techniques, this system offers simultaneous key exchange between multiple pairs of network users. A lower bound on the secure key generation rate will be derived for decoy-state quantum key distribution protocols.

  7. 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…

  8. Classic hallucinogens in the treatment of addictions.

    PubMed

    Bogenschutz, Michael P; Johnson, Matthew W

    2016-01-01

    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. PMID:25784600

  9. Stimulus Configuration, Classical Conditioning, and Hippocampal Function.

    ERIC Educational Resources Information Center

    Schmajuk, Nestor A.; DiCarlo, James J.

    1991-01-01

    The participation of the hippocampus in classical conditioning is described in terms of a multilayer network portraying stimulus configuration. A model of hippocampal function is presented, and computer simulations are used to study neural activity in the various brain areas mapped according to the model. (SLD)

  10. Quantum particles from coarse grained classical probabilities in phase space

    SciTech Connect

    Wetterich, C.

    2010-07-15

    Quantum particles can be obtained from a classical probability distribution in phase space by a suitable coarse graining, whereby simultaneous classical information about position and momentum can be lost. For a suitable time evolution of the classical probabilities and choice of observables all features of a quantum particle in a potential follow from classical statistics. This includes interference, tunneling and the uncertainty relation.

  11. Arbitrated quantum signature of classical messages without using authenticated classical channels

    NASA Astrophysics Data System (ADS)

    Luo, Yi-Ping; Hwang, Tzonelih

    2014-01-01

    This paper points out design confusion existing in all the arbitrated quantum signatures (AQS) that require public discussions over authenticated classical channels. Instead, an AQS scheme of classical messages without using authenticated classical channels is proposed here. A cryptographic hash function is used in combine with quantum mechanics to check the existence of an eavesdropping or to verify a signature. In addition, by using only single photons, this scheme provides higher efficiency both in quantum transmissions and generations. The proposed AQS scheme is shown to be immune to several well-known attacks, i.e., the Trojan-horse attacks and the existential forgery attack.

  12. 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

  13. Classical and Quantum Probability for Biologists - Introduction

    NASA Astrophysics Data System (ADS)

    Khrennikov, Andrei.

    2010-01-01

    The aim of this review (oriented to biologists looking for applications of QM) is to provide a detailed comparative analysis of classical (Kolmogorovian) and quantum (Dirac-von Neumann) models. We will stress differences in the definition of conditional probability and as a consequence in the structures of matrices of transition probabilities, especially the condition of double stochasticity which arises naturally in QM. One of the most fundamental differences between two models is deformation of the classical formula of total probability (FTP) which plays an important role in statistics and decision making. An additional term appears in the QM-version of FTP - so called interference term. Finally, we discuss Bell's inequality and show that the common viewpoint that its violation induces either nonlocality or "death of realism" has not been completely justified. For us it is merely a sign of non-Kolmogorovianity of probabilistic data collected in a few experiments with incompatible setups of measurement devices.

  14. 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.

  15. Time Monitoring Variability of Classical Be Stars

    NASA Astrophysics Data System (ADS)

    Kuhn, Benjamin; Eisner, Joshua A.; Stone, Jordan

    2016-01-01

    Classical Be stars are B type stars that show hydrogen emission in their spectra, and exhibit variability across the electromagnetic spectrum, including visible and infrared wavelengths. While spectroscopic variability in the optical range has been studied previously, the near infrared region has not been investigated as thoroughly. We present multiple epochs of near infrared spectroscopy for a sample of eight Classical Be stars. Our observations were taken using the FSPEC instrument on the 90-inch Bok reflector telescope at Kitt Peak during the months of May and June of 2010 and 2011. We targeted the Brackett Gamma emission line of hydrogen with a resolution of ≈3500. Using Python we developed tools to analyze the reduced and calibrated spectra, as well as compute equivalent widths. Time-series spectra indicate that a majority of the systems exhibit spectroscopic variability. By monitoring the strengths of the emission feature over time we aim to constrain the physical properties of these systems.

  16. Bell Experiment with Classical Optical Fields

    NASA Astrophysics Data System (ADS)

    Little, Bethany; Qian, Xiao-Feng; Howell, John; Eberly, J. H.

    We theoretically and experimentally explore the implications of entanglement in statistically classical optical fields. The description of these fields in terms of polarization and amplitude degrees of freedom can take a non-separable form which employs a mathematical description of entanglement often associated with quantum phenomena. By subjecting these optical fields to a Bell analysis, we examine the role of entanglement in marking the quantum-classical boundary. We report a value of the Bell parameter greater than calB = 2 . 54 , many standard deviations outside the limit calB = 2 established by the Clauser-Horne-Shimony-Holt Bell inequality. This suggests that Bell violation has less to do with quantum theory than previously thought, but everything to do with entanglement. University of Rochester Research Award, NSF PHY-1203931, NSF PHY-1505189, and NSF/INSPIRE PHY-1539859.

  17. 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.

  18. Experimental tests of classical and quantum dimensionality.

    PubMed

    Ahrens, Johan; Badziąg, Piotr; Pawłowski, Marcin; Zukowski, Marek; Bourennane, Mohamed

    2014-04-11

    We report on an experimental test of classical and quantum dimension. We have used a dimension witness that can distinguish between quantum and classical systems of dimensions two, three, and four and performed the experiment for all five cases. The witness we have chosen is a base of semi-device-independent cryptographic and randomness expansion protocols. Therefore, the part of the experiment in which qubits were used is a realization of these protocols. In our work we also present an analytic method for finding the maximum quantum value of the witness along with corresponding measurements and preparations. This method is quite general and can be applied to any linear dimension witness. PMID:24765923

  19. Monodisperse cluster crystals: Classical and quantum dynamics.

    PubMed

    Díaz-Méndez, Rogelio; Mezzacapo, Fabio; Cinti, Fabio; Lechner, Wolfgang; Pupillo, Guido

    2015-11-01

    We study the phases and dynamics of a gas of monodisperse particles interacting via soft-core potentials in two spatial dimensions, which is of interest for soft-matter colloidal systems and quantum atomic gases. Using exact theoretical methods, we demonstrate that the equilibrium low-temperature classical phase simultaneously breaks continuous translational symmetry and dynamic space-time homogeneity, whose absence is usually associated with out-of-equilibrium glassy phenomena. This results in an exotic self-assembled cluster crystal with coexisting liquidlike long-time dynamical properties, which corresponds to a classical analog of supersolid behavior. We demonstrate that the effects of quantum fluctuations and bosonic statistics on cluster-glassy crystals are separate and competing: Zero-point motion tends to destabilize crystalline order, which can be restored by bosonic statistics. PMID:26651695

  20. CLASSICAL CEPHEIDS REQUIRE ENHANCED MASS LOSS

    SciTech Connect

    Neilson, Hilding R.; Langer, Norbert; Izzard, Robert; Engle, Scott G.; Guinan, Ed

    2012-11-20

    Measurements of rates of period change of Classical Cepheids probe stellar physics and evolution. Additionally, better understanding of Cepheid structure and evolution provides greater insight into their use as standard candles and tools for measuring the Hubble constant. Our recent study of the period change of the nearest Cepheid, Polaris, suggested that it is undergoing enhanced mass loss when compared to canonical stellar evolution model predictions. In this work, we expand the analysis to rates of period change measured for about 200 Galactic Cepheids and compare them to population synthesis models of Cepheids including convective core overshooting and enhanced mass loss. Rates of period change predicted from stellar evolution models without mass loss do not agree with observed rates, whereas including enhanced mass loss yields predicted rates in better agreement with observations. This is the first evidence that enhanced mass loss as suggested previously for Polaris and {delta} Cephei must be a ubiquitous property of Classical Cepheids.

  1. Crossover from quantum to classical transport

    NASA Astrophysics Data System (ADS)

    Morr, Dirk K.

    2016-01-01

    Understanding the crossover from quantum to classical transport has become of fundamental importance not only for technological applications due to the creation of sub-10-nm transistors - an important building block of our modern life - but also for elucidating the role played by quantum mechanics in the evolutionary fitness of biological complexes. This article provides a basic introduction into the nature of charge and energy transport in the quantum and classical regimes. It discusses the characteristic transport properties in both limits and demonstrates how they can be connected through the loss of quantum mechanical coherence. The salient features of the crossover physics are identified, and their importance in opening new transport regimes and in understanding efficient and robust energy transport in biological complexes are demonstrated.

  2. Axions: Bose Einstein condensate or classical field?

    NASA Astrophysics Data System (ADS)

    Davidson, Sacha

    2015-05-01

    The axion is a motivated dark matter candidate, so it would be interesting to find features in Large Scale Structures specific to axion dark matter. Such features were proposed for a Bose Einstein condensate of axions, leading to confusion in the literature (to which I contributed) about whether axions condense due to their gravitational interactions. This note argues that the Bose Einstein condensation of axions is a red herring: the axion dark matter produced by the misalignment mechanism is already a classical field, which has the distinctive features attributed to the axion condensate (BE condensates are described as classical fields). This note also estimates that the rate at which axion particles condense to the field, or the field evaporates to particles, is negligible.

  3. Quantum and classical dissipation of charged particles

    SciTech Connect

    Ibarra-Sierra, V.G.; Anzaldo-Meneses, A.; Cardoso, J.L.; Hernández-Saldaña, H.; Kunold, A.; Roa-Neri, J.A.E.

    2013-08-15

    A Hamiltonian approach is presented to study the two dimensional motion of damped electric charges in time dependent electromagnetic fields. The classical and the corresponding quantum mechanical problems are solved for particular cases using canonical transformations applied to Hamiltonians for a particle with variable mass. Green’s function is constructed and, from it, the motion of a Gaussian wave packet is studied in detail. -- Highlights: •Hamiltonian of a damped charged particle in time dependent electromagnetic fields. •Exact Green’s function of a charged particle in time dependent electromagnetic fields. •Time evolution of a Gaussian wave packet of a damped charged particle. •Classical and quantum dynamics of a damped electric charge.

  4. V723 Cas a borderline classical nova

    NASA Astrophysics Data System (ADS)

    Friedjung, M.; Iijima, T.

    2002-11-01

    V723 Cas had a light curve similar to that of HR Del before maximum, with a very slow pre-maximum rise, explained according to [2] by the presence of an optically thin wind before maximum unlike the optically thick wind generally seen for classical novae after maximum. Examination of the Fe II emission lines by the SAC method, is compatible with this also having been the case for V723 Cas.

  5. 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.

  6. Mutual information in classical spin models

    NASA Astrophysics Data System (ADS)

    Wilms, Johannes; Troyer, Matthias; Verstraete, Frank

    2011-10-01

    The total many-body correlations present in finite temperature classical spin systems are studied using the concept of mutual information. As opposed to zero-temperature quantum phase transitions, the total correlations are not maximal at the phase transition, but reach a maximum in the high-temperature paramagnetic phase. The Shannon mutual information and the Renyi mutual information in both Ising and Potts models in two dimensions are calculated numerically by combining matrix product state algorithms and Monte Carlo sampling techniques.

  7. Thermal Casimir drag in fluctuating classical fields

    NASA Astrophysics Data System (ADS)

    Démery, Vincent; Dean, David S.

    2011-07-01

    A uniformly moving inclusion which locally suppresses the fluctuations of a classical thermally excited field is shown to experience a drag force that depends on the dynamics of the field. It is shown that in a number of cases the linear friction coefficient is dominated by short distance fluctuations and takes a very simple form. Examples where this drag can occur are for stiff objects, such as proteins, nonspecifically bound to more flexible ones such as polymers and membranes.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. Fundamentals of nonassociative classical field theory

    SciTech Connect

    Kurdgelaidze, D.F.

    1987-05-01

    A nonassociative classical field theory is constructed. Octonion algebra is studied. The octonion is represented as the sum of a quaternion and an associator. The octonion algebra is expanded and Lorentz group generators are specified in terms of octonion bases in one of the subalgebras. Lorentz vectors and spinors are constructed in the nonassociative algebra. The representation of the Lorentz group in terms of spin and the associator is obtained.

  13. 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.

  14. Testing for Classicality of a Physical System

    NASA Astrophysics Data System (ADS)

    Dorninger, Dietmar; Länger, Helmut

    2013-04-01

    Often quantum logics are algebraically modelled by orthomodular posets. The physical system described by such a quantum logic is classical if and only if the corresponding orthomodular poset is a Boolean algebra. We provide an easy testing procedure for this case. Moreover, we characterize orthomodular posets which are lattices and consider orthomodular posets which admit a full set of states and hence represent so-called spaces of numerical events. This way further test procedures are obtained.

  15. 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.

  16. 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.

  17. Ultra-high energy probes of classicalization

    SciTech Connect

    Dvali, Gia; Gomez, Cesar E-mail: cesar.gomez@uam.es

    2012-07-01

    Classicalizing theories are characterized by a rapid growth of the scattering cross section. This growth converts these sort of theories in interesting probes for ultra-high energy experiments even at relatively low luminosity, such as cosmic rays or Plasma Wakefield accelerators. The microscopic reason behind this growth is the production of N-particle states, classicalons, that represent self-sustained lumps of soft Bosons. For spin-2 theories this is the quantum portrait of what in the classical limit are known as black holes. We emphasize the importance of this quantum picture which liberates us from the artifacts of the classical geometric limit and allows to scan a much wider landscape of experimentally-interesting quantum theories. We identify a phenomenologically-viable class of spin-2 theories for which the growth of classicalon production cross section can be as efficient as to compete with QCD cross section already at 100TeV energy, signaling production of quantum black holes with graviton occupation number N ∼ 10{sup 4}.

  18. CLASSSTRONG: Classical simulations of strong field processes

    NASA Astrophysics Data System (ADS)

    Ciappina, M. F.; Pérez-Hernández, J. A.; Lewenstein, M.

    2014-01-01

    A set of Mathematica functions is presented to model classically two of the most important processes in strong field physics, namely high-order harmonic generation (HHG) and above-threshold ionization (ATI). Our approach is based on the numerical solution of the Newton-Lorentz equation of an electron moving on an electric field and takes advantage of the symbolic languages features and graphical power of Mathematica. Like in the Strong Field Approximation (SFA), the effects of atomic potential on the motion of electron in the laser field are neglected. The SFA was proven to be an essential tool in strong field physics in the sense that it is able to predict with great precision the harmonic (in the HHG) and energy (in the ATI) limits. We have extended substantially the conventional classical simulations, where the electric field is only dependent on time, including spatial nonhomogeneous fields and spatial and temporal synthesized fields. Spatial nonhomogeneous fields appear when metal nanosystems interact with strong and short laser pulses and temporal synthesized fields are routinely generated in attosecond laboratories around the world. Temporal and spatial synthesized fields have received special attention nowadays because they would allow to exceed considerably the conventional harmonic and electron energy frontiers. Classical simulations are an invaluable tool to explore exhaustively the parameters domain at a cheap computational cost, before massive quantum mechanical calculations, absolutely indispensable for the detailed analysis, are performed.

  19. Local purity distillation with bounded classical communication

    NASA Astrophysics Data System (ADS)

    Krovi, Hari; Devetak, Igor

    2007-07-01

    Local pure states are an important resource for quantum computing. The problem of distilling local pure states from mixed ones can be cast in an information theoretic paradigm. The bipartite version of this problem where local purity must be distilled from an arbitrary quantum state shared between two parties, Alice and Bob, is closely related to the problem of separating quantum and classical correlations in the state and in particular, to a measure of classical correlations called the one-way distillable common randomness. In Phys. Rev. A 71, 062303 (2005), the optimal rate of local purity distillation is derived when many copies of a bipartite quantum state are shared between Alice and Bob, and the parties are allowed unlimited use of a unidirectional dephasing channel. In the present paper, we extend this result to the setting in which the use of the channel is bounded. We demonstrate that in the case of a classical-quantum system, the expression for the local purity distilled is efficiently computable and provide examples with their tradeoff curves.

  20. Local Refinements in Classical Molecular Dynamics Simulations

    NASA Astrophysics Data System (ADS)

    Fackeldey, Konstantin; Weber, Marcus

    2014-03-01

    Quantum mechanics provide a detailed description of the physical and chemical behavior of molecules. However, with increasing size of the system the complexity rises exponentially, which is prohibitive for efficient dynamical simulation. In contrast, classical molecular dynamics procure a coarser description by using less degrees of freedom. Thus, it seems natural to seek for an adequate trade-off between accurateness and computational feasibility in the simulation of molecules. Here, we propose a novel method, which combines classical molecular simulations with quantum mechanics for molecular systems. For this we decompose the state space of the respective molecule into subsets, by employing a meshfree partition of unity. We show, that this partition allows us to localize an empirical force field and to run locally constrained classical trajectories. Within each subset, we compute the energy on the quantum level for a fixed number of spatial states (ab initio points). With these energy values from the ab initio points we have a local scattered data problem, which can be solved by the moving least squares method.

  1. 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

  2. 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

  3. 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

  4. 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.

  5. Mycosis fungoides: classic disease and variant presentations.

    PubMed

    Howard, M S; Smoller, B R

    2000-06-01

    Mycosis fungoides is a peripheral non-Hodgkin's T-cell neoplastic process, representing the most common type of primary cutaneous malignant lymphoma. Neoplastic lesions classically show skin predilection and characteristic clinical and histologic features in patch, plaque, and tumor stages. In addition, several clinicopathologic variants of mycosis fungoides have been delineated, including poikiloderma atrophicans vasculare (parapsoriasis variegata), Sézary syndrome, granulomatous mycosis fungoides, hypopigmented mycosis fungoides, folliculocentric mycosis fungoides, syringotropic mycosis fungoides, and Woringer Kolopp disease. We will review the salient features of patch, plaque, and tumor stage mycosis fungoides in this article and follow with a discussion of these variant clinicopathologic presentations and of therapeutic modalities. PMID:10892710

  6. 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.

  7. 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.

  8. Classical codes in quantum state space

    NASA Astrophysics Data System (ADS)

    Howard, Mark

    2015-12-01

    We present a construction of Hermitian operators and quantum states labelled by strings from a finite field. The distance between these operators or states is then simply related (typically, proportional) to the Hamming distance between their corresponding strings. This allows a straightforward application of classical coding theory to find arrangements of operators or states with a given distance distribution. Using the simplex or extended Reed-Solomon code in our construction recovers the discrete Wigner function, which has important applications in quantum information theory.

  9. 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.

  10. 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.

  11. Electroweak Baryogenesis from a Classical Force

    SciTech Connect

    Joyce, M.; Prokopec, T.; Turok, N.

    1995-08-28

    We describe a new effect that produces baryons at a first order electroweak phase transition. It operates when there is a {ital CP}-violating field present on propagating bubble walls. The novel aspect is that it involves a purely classical force, which alters the motion of particles across the wall and through diffusion creates a chiral asymmetry in front of the wall. We develop a technique for computing the baryon asymmetry using the Boltzmann equation, and a fluid approximation which allows us to model strong scattering effects. The final formula for the baryon asymmetry has a remarkably simple form.

  12. Classical Simulated Annealing Using Quantum Analogues

    NASA Astrophysics Data System (ADS)

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

    2016-06-01

    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.

  13. Non Breakable Data Encryption With Classical Information?

    NASA Astrophysics Data System (ADS)

    Kish, Laszlo B.; Sethuraman, Swaminathan; Heszler, Peter

    2005-11-01

    With the Kish-Sethuraman (KS) cipher an attempt was made, by using special operators and communication, to reach absolutely secure classical communication. First the message is bounced back with additional encryption by the Receiver and then the original encryption is removed and the message is resent by the Sender. The mechanical analogy of this operation is using two padlocks; one by the Sender and one by the Receiver. Klappenecker has pointed out that finding an efficient software realization of the operators is equivalent of proving the P ≠ NP problem. Various open problems are discussed.

  14. 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.

  15. Simple improvements to classical bubble nucleation models.

    PubMed

    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 ≃0.3σ 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. PMID:26382410

  16. 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.

  17. How quantum are classical spin ices?

    NASA Astrophysics Data System (ADS)

    Gingras, Michel J. P.; Rau, Jeffrey G.

    The pyrochlore spin ice compounds Dy2TiO7 and Ho2Ti2O7 are well described by classical Ising models down to low temperatures. Given the empirical success of this description, the question of the importance of quantum effects in these materials has been mostly ignored. We argue that the common wisdom that the strictly Ising moments of non-interacting Dy3+ and Ho3+ ions imply Ising interactions is too naive and that a more complex argument is needed to explain the close agreement between the classical Ising model theory and experiments. By considering a microscopic picture of the interactions in rare-earth oxides, we show that the high-rank multipolar interactions needed to induce quantum effects in these two materials are generated only very weakly by superexchange. Using this framework, we formulate an estimate of the scale of quantum effects in Dy2Ti2O7 and Ho2Ti2O7, finding it to be well below experimentally relevant temperatures. Published as: PHYSICAL REVIEW B 92, 144417 (2015).

  18. Classical gauged massless Rarita-Schwinger fields

    NASA Astrophysics Data System (ADS)

    Adler, Stephen L.

    2015-10-01

    We show that, in contrast to known results in the massive case, a minimally gauged massless Rarita-Schwinger field yields a consistent classical theory, with a generalized fermionic gauge invariance realized as a canonical transformation. To simplify the algebra, we study a two-component left chiral reduction of the massless theory. We formulate the classical theory in both Lagrangian and Hamiltonian form for a general non-Abelian gauging and analyze the constraints and the Rarita-Schwinger gauge invariance of the action. An explicit wave front calculation for Abelian gauge fields shows that wavelike modes do not propagate with superluminal velocities. An analysis of Rarita-Schwinger spinor scattering from gauge fields shows that adiabatic decoupling fails in the limit of zero gauge field amplitude, invalidating various "no-go" theorems based on "on-shell" methods that claim to show the impossibility of gauging Rarita-Schwinger fields. Quantization of Rarita-Schwinger fields, using many formulas from this paper, is taken up in the following paper.

  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. Relational Quadrilateralland i: the Classical Theory

    NASA Astrophysics Data System (ADS)

    Anderson, Edward

    2014-12-01

    Relational particle mechanics models bolster the relational side of the absolute versus relational motion debate. They are additionally toy models for the dynamical formulation of general relativity (GR) and its problem of time (PoT). They cover two aspects that the more commonly studied minisuperspace GR models do not: (1) by having a nontrivial notion of structure and thus of cosmological structure formation and of localized records. (2) They have linear as well as quadratic constraints, which is crucial as regards modeling many PoT facets. I previously solved relational triangleland classically, quantum mechanically and as regards a local resolution of the PoT. This rested on triangleland's shape space being 𝕊2 with isometry group SO(3), allowing for use of widely-known geometry, methods and atomic/molecular physics analogies. I now extend this work to the relational quadrilateral, which is far more typical of the general N-a-gon, represents a "diagonal to nondiagonal Bianchi IX minisuperspace" step-up in complexity, and encodes further PoT subtleties. The shape space now being ℂℙ2 with isometry group SU(3)/ℤ3, I now need to draw on geometry, shape statistics and particle physics to solve this model; this is therefore an interdisciplinary paper. This Paper treats quadrilateralland at the classical level, and then paper II provides a quantum treatment.

  1. Observables in classical canonical gravity: Folklore demystified

    NASA Astrophysics Data System (ADS)

    Pons, J. M.; Salisbury, D. C.; Sundermeyer, K. A.

    2010-04-01

    We give an overview of some conceptual difficulties, sometimes called paradoxes, that have puzzled for years the physical interpetation of classical canonical gravity and, by extension, the canonical formulation of generally covariant theories. We identify these difficulties as stemming form some terminological misunderstandings as to what is meant by "gauge invariance", or what is understood classically by a "physical state". We make a thorough analysis of the issue and show that all purported paradoxes disappear when the right terminology is in place. Since this issue is connected with the search of observables - gauge invariant quantities - for these theories, we formally show that time evolving observables can be constructed for every observer. This construction relies on the fixation of the gauge freedom of diffeomorphism invariance by means of a scalar coordinatization. We stress the condition that the coordinatization must be made with scalars. As an example of our method for obtaining observables we discuss the case of the massive particle in AdS spacetime.

  2. Optimal search behavior and classic foraging theory

    NASA Astrophysics Data System (ADS)

    Bartumeus, F.; Catalan, J.

    2009-10-01

    Random walk methods and diffusion theory pervaded ecological sciences as methods to analyze and describe animal movement. Consequently, statistical physics was mostly seen as a toolbox rather than as a conceptual framework that could contribute to theory on evolutionary biology and ecology. However, the existence of mechanistic relationships and feedbacks between behavioral processes and statistical patterns of movement suggests that, beyond movement quantification, statistical physics may prove to be an adequate framework to understand animal behavior across scales from an ecological and evolutionary perspective. Recently developed random search theory has served to critically re-evaluate classic ecological questions on animal foraging. For instance, during the last few years, there has been a growing debate on whether search behavior can include traits that improve success by optimizing random (stochastic) searches. Here, we stress the need to bring together the general encounter problem within foraging theory, as a mean for making progress in the biological understanding of random searching. By sketching the assumptions of optimal foraging theory (OFT) and by summarizing recent results on random search strategies, we pinpoint ways to extend classic OFT, and integrate the study of search strategies and its main results into the more general theory of optimal foraging.

  3. Classical and non-classical proangiogenic factors as a target of antiangiogenic therapy in tumor microenvironment.

    PubMed

    Marech, Ilaria; Leporini, Christian; Ammendola, Michele; Porcelli, Mariangela; Gadaleta, Cosmo Damiano; Russo, Emilio; De Sarro, Giovambattista; Ranieri, Girolamo

    2016-09-28

    Angiogenesis is sustained by classical and non-classical proangiogenic factors (PFs) acting in tumor microenvironment and these factors are also potential targets of antiangiogenic therapies. All PFs induce the overexpression of several signaling pathways that lead to migration and proliferation of endothelial cells contributing to tumor angiogenesis and survival of cancer cells. In this review, we have analyzed each PF with its specific receptor/s and we have summarized the available antiangiogenic drugs (e.g. monoclonal antibodies) targeting these PFs, some of these agents have already been approved, others are currently in development for the treatment of several human malignancies. PMID:26238184

  4. 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…

  5. 75 FR 19250 - Safety Zone; BWRC Spring Classic, Parker, AZ

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-14

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; BWRC Spring Classic, Parker, AZ AGENCY..., Arizona for the Blue Water Resort and Casino Spring Classic. This temporary safety zone is necessary to... Speedboat Club is sponsoring the Blue Water Resort and Casino Spring Classic, which is held on the...

  6. On the compression of information of a classical source with the use of side quantum and classical information

    NASA Astrophysics Data System (ADS)

    Molotkov, S. N.; Potapova, T. A.

    2014-06-01

    The problem of the compression of classical information when a receiver has access only to side quantum states associated with classical states of a source, which are not available directly, is examined. For the receiver to be able to reconstruct the entire information of the source, a certain additional amount of side classical information is required. A bound on the minimum necessary amount of side classical information has been obtained by simple means.

  7. Investigating Musical Performance: Commonality and Diversity among Classical and Non-Classical Musicians

    ERIC Educational Resources Information Center

    Creech, Andrea; Papageorgi, Ioulia; Duffy, Celia; Morton, Frances; Hadden, Elizabeth; Potter, John; De Bezenac, Christophe; Whyton, Tony; Himonides, Evangelos; Welch, Graham

    2008-01-01

    The research project "Investigating Musical Performance: Comparative Studies in Advanced Musical Learning" was devised to investigate how classical, popular, jazz and Scottish traditional musicians deepen and develop their learning about performance in undergraduate, postgraduate and wider music community contexts. The aim of this paper is to…

  8. 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

  9. Quantum manifestations of classical nonlinear resonances

    NASA Astrophysics Data System (ADS)

    Wisniacki, Diego A.; Schlagheck, Peter

    2015-12-01

    When an integrable classical system is perturbed, nonlinear resonances are born, grow, and eventually disappear due to chaos. In this paper the quantum manifestations of such a transition are studied in the standard map. We show that nonlinear resonances act as a perturbation that break eigenphase degeneracies for unperturbed states with quantum numbers that differ in a multiple of the order of the resonance. We show that the eigenphase splittings are well described by a semiclassical expression based on an integrable approximation of the Hamiltonian in the vicinity of the resonance. The morphology in phase space of these states is also studied. We show that the nonlinear resonance imprints a systematic influence in their localization properties

  10. Quantum manifestations of classical nonlinear resonances.

    PubMed

    Wisniacki, Diego A; Schlagheck, Peter

    2015-12-01

    When an integrable classical system is perturbed, nonlinear resonances are born, grow, and eventually disappear due to chaos. In this paper the quantum manifestations of such a transition are studied in the standard map. We show that nonlinear resonances act as a perturbation that break eigenphase degeneracies for unperturbed states with quantum numbers that differ in a multiple of the order of the resonance. We show that the eigenphase splittings are well described by a semiclassical expression based on an integrable approximation of the Hamiltonian in the vicinity of the resonance. The morphology in phase space of these states is also studied. We show that the nonlinear resonance imprints a systematic influence in their localization properties. PMID:26764790

  11. 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.

  12. Eyeblink Classical Conditioning in the Preweanling Lamb

    PubMed Central

    Johnson, Timothy B.; Stanton, Mark E.; Goodlett, Charles R.; Cudd, Timothy A.

    2010-01-01

    Classical conditioning of eyeblink responses has been one of the most important models for studying the neurobiology of learning, with many comparative, ontogenetic, and clinical applications. The current study reports the development of procedures to conduct eyeblink conditioning in preweanling lambs and demonstrates successful conditioning using these procedures. These methods will permit application of eyeblink conditioning procedures in the analysis of functional correlates of cerebellar damage in a sheep model of fetal alcohol spectrum disorders, which has significant advantages over more common laboratory rodent models. Because sheep have been widely used for studies of pathogenesis and mechanisms of injury with many different prenatal or perinatal physiological insults, eyeblink conditioning can provide a well-studied method to assess postnatal behavioral outcomes, which heretofore have not typically been pursued with ovine models of developmental insults. PMID:18513143

  13. Interaction vertex for classical spinning particles

    NASA Astrophysics Data System (ADS)

    Rempel, Trevor; Freidel, Laurent

    2016-08-01

    We consider a model of the classical spinning particle in which the coadjoint orbits of the Poincaré group are parametrized by two pairs of canonically conjugate four-vectors, one representing the standard position and momentum variables, and the other encoding the spinning degrees of freedom. This "dual phase space model" is shown to be a consistent theory of both massive and massless particles and allows for coupling to background fields such as electromagnetism. The on-shell action is derived and shown to be a sum of two terms, one associated with motion in spacetime, and the other with motion in "spin space." Interactions between spinning particles are studied, and a necessary and sufficient condition for consistency of a three-point vertex is established.

  14. Unpolarized light: Classical and quantum states

    NASA Astrophysics Data System (ADS)

    Lehner, J.; Leonhardt, U.; Paul, H.

    1996-04-01

    We give a general definition of unpolarized light that rests on invariance properties rather than specific values of second-order field correlations or, equivalently, the Stokes parameters. It turns out that to require invariance with respect to rotation around the propagation axis and symmetry with respect to left- and right-handed circular polarization is not sufficient to fully characterize completely unpolarized light, such as natural light. Actually, a third requirement demanding invariance with respect to phase retardation is needed. Depending on whether it is satisfied or not, we speak of type I or type II unpolarized light, and we specify the general form of both classical distribution functions and density operators consistent with the respective conditions.

  15. 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.

  16. A Classic Clinical Case: Neutrophilic Eccrine Hidradenitis

    PubMed Central

    Copaescu, Ana-Maria; Castilloux, Jean-François; Chababi-Atallah, Myrna; Sinave, Christian; Bertrand, Janie

    2013-01-01

    Background Neutrophilic eccrine hidradenitis (NEH) is a rare condition described mostly in adult patients receiving chemotherapy for acute myelogenous leukemia. When it affects the facial region, it can mimic cellulitis and delay the diagnostic, thus proper recognition is essential. Objective This article describes a classic case of NEH. We will review the diagnostic, the differential diagnostic (mostly cellulitis) and the management of this condition. Methods After a literature review, the patient's file was properly studied in order to portray a clear picture of this condition. Medical photographs and appropriate physical examination upon presentation are also included. Results The diagnostic for NEH was suggested by the clinical presentation and confirmed histopathologically (skin biopsy). Conclusion The diagnostic of NEH is essential in order to prevent multiple unnecessary antibiotics. PMID:24474918

  17. 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.

  18. Classical chromodynamics and heavy ion collisions

    NASA Astrophysics Data System (ADS)

    Lappi, T.

    2005-05-01

    This paper is a slightly modified version of the introductory part of a doctoral dissertation also containing the articles hep-ph/0303076, hep-ph/0409328 and hep-ph/0409058. The paper focuses on the calculation of particle production in a relativistic heavy ion collision using the McLerran-Venugopalan model. The main part of the paper summarizes the background of these numerical calculations. First we relate this calculation of the initial stage af a heavy ion collision to our understanding of the whole collision process. Then we discuss the saturation physics of the small x wavefunction of a hadron or a nucleus. The classical field model of Kovner, McLerran and Weigert is then introduced before moving to discuss the numerical algorithms used to compute gluon and quark pair production in this model. Finally we shortly review the results on gluon and quark-antiquark production obtained in the three articles mentioned above.

  19. 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.

  20. Classical medicine v alternative medical practices.

    PubMed Central

    Kottow, M H

    1992-01-01

    Classical medicine operates in a climate of rational discourse, scientific knowledge accretion and the acceptance of ethical standards that regulate its activities. Criticism has centred on the excessive technological emphasis of modern medicine and on its social strategy aimed at defending exclusiveness and the privileges of professional status. Alternative therapeutic approaches have taken advantage of the eroded public image of medicine, offering treatments based on holistic philosophies that stress the non-rational, non-technical and non-scientific approach to the unwell, disregarding traditional diagnostic categories and concentrating on enhancing subjective comfort and well-being, but remaining oblivious to the organic substrate of disease. This leads to questionable ethics in terms of false hopes and lost opportunities for effective therapy. PMID:1573644

  1. Observational selection among classical novae in outburst.

    NASA Astrophysics Data System (ADS)

    Ritter, H.; Politano, M. J.; Livio, M.; Webbink, R. F.

    The authors investigate to what extent observational selection can account for the prevalence of massive white dwarfs among classical novae as was originally proposed by Truran and Livio (1986). For this the authors elaborate on their approach by taking into account a detailed model distribution function for the masses of newly-formed cataclysmic binaries from Politano (1988, 1990), an improved ignition condition for the thermonuclear runaway, as well as effects of the secular evolution of the systems and flux limitation of the observations (including interstellar absorption). The results agree qualitatively with those obtained by Truran and Livio (1986). However, since Politano's model calculations do not take into account the formation of O-Ne-Mg white dwarfs, the authors cannot make any quantitative prediction as to their expected abundance among observed novae.

  2. Nonlinear quantum equations: Classical field theory

    SciTech Connect

    Rego-Monteiro, M. A.; Nobre, F. D.

    2013-10-15

    An exact classical field theory for nonlinear quantum equations is presented herein. It has been applied recently to a nonlinear Schrödinger equation, and it is shown herein to hold also for a nonlinear generalization of the Klein-Gordon equation. These generalizations were carried by introducing nonlinear terms, characterized by exponents depending on an index q, in such a way that the standard, linear equations, are recovered in the limit q→ 1. The main characteristic of this field theory consists on the fact that besides the usual Ψ(x(vector sign),t), a new field Φ(x(vector sign),t) needs to be introduced in the Lagrangian, as well. The field Φ(x(vector sign),t), which is defined by means of an additional equation, becomes Ψ{sup *}(x(vector sign),t) only when q→ 1. The solutions for the fields Ψ(x(vector sign),t) and Φ(x(vector sign),t) are found herein, being expressed in terms of a q-plane wave; moreover, both field equations lead to the relation E{sup 2}=p{sup 2}c{sup 2}+m{sup 2}c{sup 4}, for all values of q. The fact that such a classical field theory works well for two very distinct nonlinear quantum equations, namely, the Schrödinger and Klein-Gordon ones, suggests that this procedure should be appropriate for a wider class nonlinear equations. It is shown that the standard global gauge invariance is broken as a consequence of the nonlinearity.

  3. 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

  4. 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. PMID:27113815

  5. 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. PMID:23242261

  6. 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.

  7. 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.

  8. 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.

  9. Krakatau 1883: A classic geophysical event

    NASA Astrophysics Data System (ADS)

    Simkin, Tom; Fiske, Richard S.

    This week marks the 100th anniversary of Krakatau's 1883 eruption, perhaps the most famous volcanic event in recorded history. During a 23-hour period on August 26 and 27, 1883, more than 18 km3 of volcanic debris thundered upward from Krakatau, resulting in the death of more than 36,000 people and causing widespread devastation to the surrounding area. Moreover, the 1883 events at Krakatau caused geophysical phenomena that were observed around the world, making it (at least up until Mount St. Helens' 1980 eruption) the household word for a classic volcanic catastrophe.One hundred years ago, Krakatau was a 5×9 km island in the Sunda Straits, between Java and Sumatra in the Dutch East Indies. It was a familiar landmark, both to the tens of thousands of nearby coastal residents and to the crews of thousands of ships from Europe and the Americas that passed through the Straits each year on their way to and from the far east. The volcano had last erupted in 1681 and was not regarded as a likely site for renewed and catastrophic activity.

  10. 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.

  11. Resolution of a paradox in classical electrodynamics

    SciTech Connect

    Pinto, Fabrizio

    2006-05-15

    It is an early result of electrostatics in curved space that the gravitational mass of a charge distribution changes by an amount equal to U{sub es}/c{sup 2}, where U{sub es} is the internal electrostatic potential energy and c is the speed of light, if the system is supported at rest by external forces. This fact, independently rediscovered in recent years in the case of a simple dipole, confirms a very reasonable expectation grounded in the mass-energy equivalency equation. However, it is an unsolved paradox of classical electrodynamics that the renormalized mass of an accelerated dipole calculated from the self-forces due to the distortion of the Coulomb field differs in general from that expected from the energy correction, U{sub es}/c{sup 2}, unless the acceleration is transversal to the orientation of the dipole. Here we show that this apparent paradox disappears for any dipole orientation if the self-force is evaluated by means of Whittaker's exact solution for the field of the single charge in a homogeneous gravitational field described in the Rindler metric. The discussion is supported by computer algebra results, diagrams of the electric fields distorted by gravitation, and a brief analysis of the prospects for realistic experimentation. The gravitational correction to dipole-dipole interactions is also discussed.

  12. Quantum-classical lifetimes of Rydberg molecules

    NASA Astrophysics Data System (ADS)

    Junginger, Andrej; Main, Jörg; Wunner, Günter

    2013-04-01

    A remarkable property of Rydberg atoms is the possibility of creating molecules formed by one highly excited atom and another atom in the ground state. The first realization of such a Rydberg molecule has opened an active field of physical investigations, and showed that its basic properties can be described within a simple model regarding the ground state atom as a small perturber that is bound by a low-energy scattering process with the Rydberg electron (Greene et al 2000 Phys. Rev. Lett. 85 2458). Besides the good agreement between theory and the experiment concerning the vibrational states of the molecule, the experimental observations yield the astonishing feature that the lifetime of the molecule is clearly reduced as compared to the bare Rydberg atom (Butscher et al 2011 J. Phys. B: At. Mol. Opt. Phys. 44 184004). With focus on this yet unexplained observation, we investigate in this paper the vibrational ground state of the molecule in a quantum-classical framework. We show that the Rydberg wavefunction is continuously detuned by the presence of the moving ground state atom and that the timescale on which the detuning significantly exceeds the natural linewidth is in good agreement with the observed reduced lifetimes of the Rydberg molecule.

  13. Classical probability model for Bell inequality

    NASA Astrophysics Data System (ADS)

    Khrennikov, Andrei

    2014-04-01

    We show that by taking into account randomness of realization of experimental contexts it is possible to construct common Kolmogorov space for data collected for these contexts, although they can be incompatible. We call such a construction "Kolmogorovization" of contextuality. This construction of common probability space is applied to Bell's inequality. It is well known that its violation is a consequence of collecting statistical data in a few incompatible experiments. In experiments performed in quantum optics contexts are determined by selections of pairs of angles (θi,θ'j) fixing orientations of polarization beam splitters. Opposite to the common opinion, we show that statistical data corresponding to measurements of polarizations of photons in the singlet state, e.g., in the form of correlations, can be described in the classical probabilistic framework. The crucial point is that in constructing the common probability space one has to take into account not only randomness of the source (as Bell did), but also randomness of context-realizations (in particular, realizations of pairs of angles (θi, θ'j)). One may (but need not) say that randomness of "free will" has to be accounted for.

  14. 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.

  15. 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

  16. 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.

  17. 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.

  18. Critical viscosity exponent for classical fluids

    NASA Astrophysics Data System (ADS)

    Hao, Hong; Ferrell, Richard A.; Bhattacharjee, Jayanta K.

    2005-02-01

    A self-consistent mode-coupling calculation of the critical viscosity exponent zη for classical fluids is performed by including the memory effect and the vertex corrections. The incorporation of the memory effect is through a self-consistency procedure that evaluates the order parameter and shear momentum relaxation rates at nonzero frequencies, thereby taking their frequency dependence into account. This approach offers considerable simplification and efficiency in the calculation. The vertex corrections are also demonstrated to have significant effects on the numerical value for the critical viscosity exponent, in contrast to some previous theoretical work which indicated that the vertex corrections tend to cancel out from the final result. By carrying out all of the integrations analytically, we have succeeded in tracing the origin of this discrepancy to an error in earlier work. We provide a thorough treatment of the two-term epsilon expansion, as well as a complete three-dimensional analysis of the fluctuating order-parameter and transverse hydrodynamic modes. The study of the interactions of these modes is carried out to high order so as to arrive at zη=0.0679±0.0007 for comparison with the experimentally observed value, 0.0690±0.0006 .

  19. Generalized fluctuation theorems for classical systems

    NASA Astrophysics Data System (ADS)

    Agarwal, G. S.; Dattagupta, Sushanta

    2015-11-01

    The fluctuation theorem has a very special place in the study of nonequilibrium dynamics of physical systems. The form in which it is used most extensively is the Gallavoti-Cohen fluctuation theorem which is in terms of the distribution of the work p (W )/p (-W )=exp(α W ) . We derive the general form of the fluctuation theorems for an arbitrary multidimensional Gaussian Markov process. Interestingly, the parameter α is by no means universal, hitherto taken for granted in the case of linear Gaussian processes. As a matter of fact, conditions under which α does become a universal parameter 1 /K T are found to be rather restrictive. As an application we consider fluctuation theorems for classical cyclotron motion of an electron in a parabolic potential. The motion of the electron is described by four coupled Langevin equations and thus is nontrivial. The generalized theorems are equally valid for nonequilibrium steady states and could be especially important in the presence of anisotropic diffusion.

  20. 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.

  1. Symmetry constraints on the classical skyrmion

    SciTech Connect

    Samiullah, M.; Rolnick, P.

    1995-04-01

    We derive the constraints on the solutions of the classical SU(2) Skyrme model imposed by requiring that angular momentum ({bold J}) and isospin ({bold I}) be well defined under the general symmetry ({ital aI}{sub 3}+{ital bJ}{sub 3}). We show that for all nontrivial solutions ({ital aI}{sub 3}+{ital bJ}{sub 3}) must be 0, {ital a}/{ital b} must be an integer, and for {ital b}{ne}0 the profile function must be of the form {bold F}({bold r})={ital F}((1{minus}{ital A}{sup 2}){sup 1/2}{cflx z}+{ital A} {l_brace}{cflx x}cos[({ital a}/{ital b}){phi}+{ital B}]+{cflx y}sin[({ital a}/{ital b}){phi}]+{ital B}{r_brace})({cflx x},{cflx y},{cflx z} are Cartesian unit vectors; {ital r},{theta},{phi} are the usual spherical polar coordinates; {ital F}, {ital A}, {ital B} are undetermined functions of {ital r},{theta}).

  2. Treatment regimens of classical and newer taxanes.

    PubMed

    Joerger, Markus

    2016-02-01

    The classical taxanes (paclitaxel, docetaxel), the newer taxane cabazitaxel and the nanoparticle-bound nab-paclitaxel are among the most widely used anticancer drugs. The taxanes share the characteristics of extensive hepatic metabolism and biliary excretion, the need for dose adaptation in patients with liver dysfunction, and a substantial pharmacokinetic variability even after taking into account known covariates. Data from clinical studies suggest that optimal scheduling of the taxanes is dependent not only on the specific taxane compound, but also on the tumor type and line of treatment. Still, the optimal dosing regimen (weekly vs 3 weekly) and optimal dose of the taxanes are controversial, as is the value of pharmacological personalization of taxane dosing. In this article, an overview is given on the pharmacological properties of the taxanes, including metabolism, pharmacokinetics-pharmacodynamics and aspects in the clinical use of taxanes. The latter includes the ongoing debate on the most active and safe regimen, the recommended initial dose and the issue of therapeutic drug dosing. PMID:26589792

  3. Local thermonuclear runaways among classical novae

    NASA Astrophysics Data System (ADS)

    Orio, Marina; Shaviv, Giora

    1993-04-01

    A classical nova may accrete a nonhomogeneous envelope, which can result in the ignition of a local thermonuclear runaway on the surface of the white dwarf. We studied the propagation of thermal flows along the meridian in the hydrogen rich envelope, to find the conditions under which a thermonuclear runaway is not spherically symmetric. We included mass accretion and tested the effect of temperature inhomogeneities in the secular evolution of the envelope, supposing perturbations with different wavelengths, ranging from very small to comparable with the radius of the white dwarf. The calculations were stopped at the onset of a thermonuclear runaway, when the hydrodynamic expansion starts. We found the ranges of accretion rates and masses of white dwarfs for which the runaway ignites locally. The propagation time of the runaway along the meridian may be as long as days and weeks. 'Local' thermonuclear runaways can explain the asymmetries and inhomogeneities of the nova shells and account for the slow rise time to maximum (about one week) of many novae.

  4. A critical review of classical bouncing cosmologies

    NASA Astrophysics Data System (ADS)

    Battefeld, Diana; Peter, Patrick

    2015-04-01

    Given the proliferation of bouncing models in recent years, we gather and critically assess these proposals in a comprehensive review. The PLANCK data shows an unmistakably red, quasi scale-invariant, purely adiabatic primordial power spectrum and no primary non-Gaussianities. While these observations are consistent with inflationary predictions, bouncing cosmologies aspire to provide an alternative framework to explain them. Such models face many problems, both of the purely theoretical kind, such as the necessity of violating the NEC and instabilities, and at the cosmological application level, as exemplified by the possible presence of shear. We provide a pedagogical introduction to these problems and also assess the fitness of different proposals with respect to the data. For example, many models predict a slightly blue spectrum and must be fine-tuned to generate a red spectral index; as a side effect, large non-Gaussianities often result. We highlight several promising attempts to violate the NEC without introducing dangerous instabilities at the classical and/or quantum level. If primordial gravitational waves are observed, certain bouncing cosmologies, such as the cyclic scenario, are in trouble, while others remain valid. We conclude that, while most bouncing cosmologies are far from providing an alternative to the inflationary paradigm, a handful of interesting proposals have surfaced, which warrant further research. The constraints and lessons learned as laid out in this review might guide future research.

  5. Indeterminism in Classical Dynamics of Particle Motion

    NASA Astrophysics Data System (ADS)

    Eyink, Gregory; Vishniac, Ethan; Lalescu, Cristian; Aluie, Hussein; Kanov, Kalin; Burns, Randal; Meneveau, Charles; Szalay, Alex

    2013-03-01

    We show that ``God plays dice'' not only in quantum mechanics but also in the classical dynamics of particles advected by turbulent fluids. With a fixed deterministic flow velocity and an exactly known initial position, the particle motion is nevertheless completely unpredictable! In analogy with spontaneous magnetization in ferromagnets which persists as external field is taken to zero, the particle trajectories in turbulent flow remain random as external noise vanishes. The necessary ingredient is a rough advecting field with a power-law energy spectrum extending to smaller scales as noise is taken to zero. The physical mechanism of ``spontaneous stochasticity'' is the explosive dispersion of particle pairs proposed by L. F. Richardson in 1926, so the phenomenon should be observable in laboratory and natural turbulent flows. We present here the first empirical corroboration of these effects in high Reynolds-number numerical simulations of hydrodynamic and magnetohydrodynamic fluid turbulence. Since power-law spectra are seen in many other systems in condensed matter, geophysics and astrophysics, the phenomenon should occur rather widely. Fast reconnection in solar flares and other astrophysical systems can be explained by spontaneous stochasticity of magnetic field-line motion

  6. Classical and quantum superintegrability with applications

    NASA Astrophysics Data System (ADS)

    Miller, Willard, Jr.; Post, Sarah; Winternitz, Pavel

    2013-10-01

    A superintegrable system is, roughly speaking, a system that allows more integrals of motion than degrees of freedom. This review is devoted to finite dimensional classical and quantum superintegrable systems with scalar potentials and integrals of motion that are polynomials in the momenta. We present a classification of second-order superintegrable systems in two-dimensional Riemannian and pseudo-Riemannian spaces. It is based on the study of the quadratic algebras of the integrals of motion and on the equivalence of different systems under coupling constant metamorphosis. The determining equations for the existence of integrals of motion of arbitrary order in real Euclidean space E2 are presented and partially solved for the case of third-order integrals. A systematic exposition is given of systems in two and higher dimensional space that allow integrals of arbitrary order. The algebras of integrals of motions are not necessarily quadratic but close polynomially or rationally. The relation between superintegrability and the classification of orthogonal polynomials is analyzed.

  7. Classical and quantum routes to linear magnetoresistance.

    PubMed

    Hu, Jingshi; Rosenbaum, T F

    2008-09-01

    The hallmark of materials science is the ability to tailor the microstructure of a given material to provide a desired response. Carbon mixed with iron provides the steel of buildings and bridges; impurities sprinkled in silicon single crystals form the raw materials of the electronics revolution; pinning centres in superconductors let them become powerful magnets. Here, we show that either adding a few parts per million of the proper chemical impurities to indium antimonide, a well-known semiconductor, or redesigning the material's structure on the micrometre scale, can transform its response to an applied magnetic field. The former approach is purely quantum mechanical; the latter a classical outgrowth of disorder, turned to advantage. In both cases, the magnetoresistive response--at the heart of magnetic sensor technology--can be converted to a simple, large and linear function of field that does not saturate. Harnessing the effects of disorder has the further advantage of extending the useful applications range of such a magnetic sensor to very high temperatures by circumventing the usual limitations imposed by phonon scattering. PMID:18719705

  8. Embedding quantum into classical: contextualization vs conditionalization.

    PubMed

    Dzhafarov, Ehtibar N; Kujala, Janne V

    2014-01-01

    We compare two approaches to embedding joint distributions of random variables recorded under different conditions (such as spins of entangled particles for different settings) into the framework of classical, Kolmogorovian probability theory. In the contextualization approach each random variable is "automatically" labeled by all conditions under which it is recorded, and the random variables across a set of mutually exclusive conditions are probabilistically coupled (imposed a joint distribution upon). Analysis of all possible probabilistic couplings for a given set of random variables allows one to characterize various relations between their separate distributions (such as Bell-type inequalities or quantum-mechanical constraints). In the conditionalization approach one considers the conditions under which the random variables are recorded as if they were values of another random variable, so that the observed distributions are interpreted as conditional ones. This approach is uninformative with respect to relations between the distributions observed under different conditions because any set of such distributions is compatible with any distribution assigned to the conditions. PMID:24681665

  9. Embedding Quantum into Classical: Contextualization vs Conditionalization

    PubMed Central

    Dzhafarov, Ehtibar N.; Kujala, Janne V.

    2014-01-01

    We compare two approaches to embedding joint distributions of random variables recorded under different conditions (such as spins of entangled particles for different settings) into the framework of classical, Kolmogorovian probability theory. In the contextualization approach each random variable is “automatically” labeled by all conditions under which it is recorded, and the random variables across a set of mutually exclusive conditions are probabilistically coupled (imposed a joint distribution upon). Analysis of all possible probabilistic couplings for a given set of random variables allows one to characterize various relations between their separate distributions (such as Bell-type inequalities or quantum-mechanical constraints). In the conditionalization approach one considers the conditions under which the random variables are recorded as if they were values of another random variable, so that the observed distributions are interpreted as conditional ones. This approach is uninformative with respect to relations between the distributions observed under different conditions because any set of such distributions is compatible with any distribution assigned to the conditions. PMID:24681665

  10. Classical oscillators in the control of quantum tunneling: Numerical experiments

    NASA Astrophysics Data System (ADS)

    Kar, Susmita; Bhattacharyya, S. P.

    2016-06-01

    The dynamics of a classical anharmonic oscillator is exploited to control the tunneling dynamics of a quantum particle to which the classical oscillator is coupled. The mixed quantum classical problem is investigated at a mean-field like level. The anharmonic strength (λ) , particle mass (Mc) and harmonic stiffness (ωc) of the classical controller are explored as possible control parameters for the tunneling dynamics. The strength, the type of coupling between the quantum system and classical controller and the effective frequency of the controller emerge as crucial factors in shaping the nature and extent of the control. A whole spectrum of possibilities starting from enhancement, suppression to complete destruction of tunneling emerge depending on values assigned to the control parameters, the type of coupling and the control configuration used. When classical controller is replaced by a quantum controller, the control landscape becomes much simpler.

  11. On the correspondence between quantum and classical variational principles

    SciTech Connect

    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.

  12. 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.

  13. On the correspondence between quantum and classical variational principles

    DOE PAGESBeta

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

    2015-10-01

    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. (C) 2015 Elsevier B.V. All rights reserved.

  14. On the correspondence between quantum and classical variational principles

    NASA Astrophysics Data System (ADS)

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

    2015-10-01

    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 Schrödinger, Pauli, and Klein-Gordon particles.

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

    PubMed

    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

  16. Classical Dynamics Based on the Minimal Length Uncertainty Principle

    NASA Astrophysics Data System (ADS)

    Chung, Won Sang

    2016-02-01

    In this paper we consider the quadratic modification of the Heisenberg algebra and its classical limit version which we call the β-deformed Poisson bracket for corresponding classical variables. We use the β-deformed Poisson bracket to discuss some physical problems in the β-deformed classical dynamics. Finally, we consider the ( α, β)- deformed classical dynamics in which minimal length uncertainty principle is given by [ hat {x} , hat {p}] = i hbar (1 + α hat {x}2 + β hat {p}2 ) . For two small parameters α, β, we discuss the free fall of particle and a composite system in a uniform gravitational field.

  17. Sharing the Quantum State and the Classical Information Simultaneously

    NASA Astrophysics Data System (ADS)

    Qin, Huawang; Dai, Yuewei

    2016-04-01

    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.

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. Exploring Classically Chaotic Potentials with a Matter Wave Quantum Probe

    SciTech Connect

    Gattobigio, G. L.; Couvert, A.; Georgeot, B.; Guery-Odelin, D.

    2011-12-16

    We study an experimental setup in which a quantum probe, provided by a quasimonomode guided atom laser, interacts with a static localized attractive potential whose characteristic parameters are tunable. In this system, classical mechanics predicts a transition from regular to chaotic behavior as a result of the coupling between the different degrees of freedom. Our experimental results display a clear signature of this transition. On the basis of extensive numerical simulations, we discuss the quantum versus classical physics predictions in this context. This system opens new possibilities for investigating quantum scattering, provides a new testing ground for classical and quantum chaos, and enables us to revisit the quantum-classical correspondence.

  3. 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.

  4. Classical Novae in the Swift Era

    NASA Astrophysics Data System (ADS)

    Starrfield, Sumner; Swift-Nova-CV Group

    2008-03-01

    One of the highlights of Swift is that it is a remarkably responsive spacecraft both because of its design and because Neil Gehrels, the PI, is attuned to the great science that can be done with Targets of Opportunity. As a result, we have made important and significant discoveries about the X-ray evolution of Cataclysmic Variables (CV) in general and both Classical (CN) and Recurrent Novae (RN) in particular. Before Swift, both CN and RN were known to emit in both hard and soft X-rays but observations were few, with only a small number of CNe followed through their X-ray bright phase. We have now extended X-ray observations to many more CNe which has answered some questions and, at least as important, posed new questions about the evolution of the explosion. I emphasize that X-ray observations are the only means of following the evolution of the nuclear-burning white dwarf during the outburst. I will review our observations of CN and concentrate on the SSS phase in which the X-ray emission is coming from hot, nuclear-burning, white dwarf outer layers and atmosphere. I will present a brief summary of our results on the 2006 outburst of RS Oph in which a RN was detected with the BAT and then, later, we observed the turn-on of the SSS phase some 26 days into outburst. Finally, I will discuss V723 Cas (1995) which now holds the record for the longest CN observed in outburst in X-rays. I gratefully acknowledge partial support from NSF and NASA grants to ASU and to the members of the Swift-NOVA-CV working group who obtained, extracted, and analyzed the data that I will be presenting.

  5. [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

  6. 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.

  7. 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)…

  8. 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)

  9. Ghost imaging of phase objects with classical incoherent light

    SciTech Connect

    Shirai, Tomohiro; Setaelae, Tero; Friberg, Ari T.

    2011-10-15

    We describe an optical setup for performing spatial Fourier filtering in ghost imaging with classical incoherent light. This is achieved by a modification of the conventional geometry for lensless ghost imaging. It is shown on the basis of classical coherence theory that with this technique one can realize what we call phase-contrast ghost imaging to visualize pure phase objects.

  10. Algorithms for Computerized Test Construction Using Classical Item Parameters.

    ERIC Educational Resources Information Center

    Adema, Jos J.; van der Linden, Wim J.

    1989-01-01

    Two zero-one linear programing models for constructing tests using classical item and test parameters are given. These models are useful, for instance, when classical test theory must serve as an interface between an item response theory-based item banking system and a test constructor unfamiliar with the underlying theory. (TJH)

  11. 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.

  12. Extracting classical correlations from a bipartite quantum system

    SciTech Connect

    Hamieh, S.; Qi, J.; Siminovitch, D.; Ali, M.K.

    2003-01-01

    In this paper, we discuss the problem of splitting of the total correlations for a bipartite quantum state described by the Von Neumann mutual information into classical and quantum parts. We propose a measure of the classical correlations as the difference between the Von Neumann mutual information and the relative entropy of entanglement. We compare this measure with different measures proposed in the literature.

  13. 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.

  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. 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…

  16. 78 FR 19988 - Safety Zone; BWRC Spring Classic, Parker, AZ

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-03

    ... Security FR Federal Register NPRM Notice of Proposed Rulemaking A. Regulatory History and Information The... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; BWRC Spring Classic, Parker, AZ AGENCY..., Arizona for the Blue Water Resort and Casino Spring Classic. This temporary safety zone is necessary...

  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. 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…

  19. In Search of Introductory Psychology's Classic Core Vocabulary.

    ERIC Educational Resources Information Center

    Griggs, Richard A.; Mitchell, Montserrat C.

    2002-01-01

    Examines whether there was a common vocabulary present within introductory psychology textbooks during the 1950s and if a classic core vocabulary exists. Reports that no common core existed in the textbooks during the 1950s, but there is a set of 100 classic vocabulary terms. (CMK)

  20. 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,…

  1. 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)

  2. 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.

  3. 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…

  4. Classical and thermodynamic limits for generalised quantum spin systems

    NASA Astrophysics Data System (ADS)

    Duffield, N. G.

    1990-01-01

    We prove that the rescaled upper and lower symbols for arbitrary generalised quantum spin systems converge in the classical limit. For a large class of models this enables us to derive the asyptotics of quantum free energies in the classical and in the thermodynamic limit.

  5. 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…

  6. A new classical conjugate gradient coefficient with exact line search

    NASA Astrophysics Data System (ADS)

    Shapiee, Norrlaili; Rivaie, Mohd.; Mamat, Mustafa

    2016-06-01

    In this paper, we proposed a new classical conjugate gradient method. The global convergence is established using exact line search. Numerical results are presented based on number of iterations and CPU time. This numerical result shows that our method is performs better than classical CG method for a given standard test problems.

  7. The Classical Greek Program in the School District of Philadelphia.

    ERIC Educational Resources Information Center

    Masciantonio, Rudolph

    Classical Greek is taught as an elective to over 200 students in seven secondary schools of the School District of Philadelphia. In the past decade the restoration of Greek studies to the classical curriculum was called for, and in 1968 a Greek Curriculum Committee was established in Philadelphia to develop a program and instructional materials.…

  8. 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:…

  9. 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…

  10. Quantum-classical equivalence and ground-state factorization

    NASA Astrophysics Data System (ADS)

    Abouie, Jahanfar; Sepehrinia, Reza

    2016-02-01

    We have performed an analytical study of quantum-classical equivalence for quantum XY-spin chains with arbitrary interactions to explore the classical counterpart of the factorizing magnetic fields that drive the system into a separable ground state. We demonstrate that the factorizing line in the parameter space of a quantum model is equivalent to the so-called natural boundary that emerges in mapping the quantum XY-model onto the two-dimensional classical Ising model. As a result, we show that the quantum systems with the non-factorizable ground state could not be mapped onto the classical Ising model. Based on the presented correspondence we suggest a promising method for obtaining the factorizing field of quantum systems through the commutation of the quantum Hamiltonian and the transfer matrix of the classical model.

  11. Fate of classical solitons in one-dimensional quantum systems.

    SciTech Connect

    Pustilnik, M.; Matveev, K. A.

    2015-11-23

    We study one-dimensional quantum systems near the classical limit described by the Korteweg-de Vries (KdV) equation. The excitations near this limit are the well-known solitons and phonons. The classical description breaks down at long wavelengths, where quantum effects become dominant. Focusing on the spectra of the elementary excitations, we describe analytically the entire classical-to-quantum crossover. We show that the ultimate quantum fate of the classical KdV excitations is to become fermionic quasiparticles and quasiholes. We discuss in detail two exactly solvable models exhibiting such crossover, the Lieb-Liniger model of bosons with weak contact repulsion and the quantum Toda model, and argue that the results obtained for these models are universally applicable to all quantum one-dimensional systems with a well-defined classical limit described by the KdV equation.

  12. Fundamental theories of waves and particles formulated without classical mass

    SciTech Connect

    Fry, J.L.; Musielak, Z.E.

    2010-12-15

    Quantum and classical mechanics are two conceptually and mathematically different theories of physics, and yet they do use the same concept of classical mass that was originally introduced by Newton in his formulation of the laws of dynamics. In this paper, physical consequences of using the classical mass by both theories are explored, and a novel approach that allows formulating fundamental (Galilean invariant) theories of waves and particles without formally introducing the classical mass is presented. In this new formulation, the theories depend only on one common parameter called 'wave mass', which is deduced from experiments for selected elementary particles and for the classical mass of one kilogram. It is shown that quantum theory with the wave mass is independent of the Planck constant and that higher accuracy of performing calculations can be attained by such theory. Natural units in connection with the presented approach are also discussed and justification beyond dimensional analysis is given for the particular choice of such units.

  13. 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.

  14. Comparision of laser-induced and classical ultasound

    NASA Astrophysics Data System (ADS)

    Niederhauser, Joel J.; Jaeger, Michael; Frenz, Martin

    2003-06-01

    A classical medical ultrasound system was combined with a pulsed laser source to allow laser-induced ultrasound imaging (optoacoustics). Classical ultrasound is based on reflection and scattering of an incident acoustic pulse at internal tissue structures. Laser-induced ultrasound is generated in situ by heating optical absorbing structures, such as blood vessels, with a 5 ns laser pulse (few degrees or fraction of degree), which generates pressure transients. Laser-induced ultrasound probes optical properties and therefore provides much higher contrast and complementary information compared to classical ultrasound. An ultrasound array transducer in combination with a commercial medical imaging system was used to record acoustic transients of both methods. Veins and arteries in a human forearm were identified in vivo using classical color doppler and oxygenation dependent optical absorption at 660 nm and 1064 nm laser wavelength. Safety limits of both methods were explored. Laser-induced ultrasound seems well suited to improve classical ultrasound imaging of subcutaneous regions.

  15. 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.

  16. Nonclassical polarization dynamics in classical-like states

    NASA Astrophysics Data System (ADS)

    Luis, Alfredo; Sanz, Ángel S.

    2015-08-01

    Quantum polarization is investigated by means of a trajectory picture based on the Bohmian formulation of quantum mechanics. Relevant examples of classical-like two-mode field states are thus examined, namely, Glauber and SU(2) coherent states. Although these states are often regarded as classical, the analysis here shows that the corresponding electric-field polarization trajectories display topologies very different from those expected from classical electrodynamics. Rather than incompatibility with the usual classical model, this result demonstrates the dynamical richness of quantum motions, determined by local variations of the system quantum phase in the corresponding (polarization) configuration space, absent in classical-like models. These variations can be related to the evolution in time of the phase, but also to its dependence on configurational coordinates, which is the crucial factor to generate motion in the case of stationary states like those considered here. In this regard, for completeness these results are compared with those obtained from nonclassical NOON states.

  17. Mycobacterium tuberculosis infection of the 'non-classical immune cell'.

    PubMed

    Randall, Philippa J; Hsu, Nai-Jen; Quesniaux, Valerie; Ryffel, Bernhard; Jacobs, Muazzam

    2015-10-01

    Mycobacterium tuberculosis can infect 'non-classical immune cells', which comprise a significant constituency of cells that reside outside of those defined as 'classical immune cells' from myeloid or lymphoid origin. Here we address the influence of specific 'non-classical immune cells' in host responses and their effects in controlling mycobacterial growth or enabling an environment conducive for bacilli persistence. The interaction of M. tuberculosis with epithelial cells, endothelial cells, fibroblasts, adipocytes, glia and neurons and downstream cellular responses that often dictate immune regulation and disease outcome are discussed. Functional integration and synergy between 'classical' and 'non-classical immune cells' are highlighted as critical for determining optimal immune outcomes that favour the host. PMID:25801479

  18. 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. PMID:26126772

  19. 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

  20. 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

    1. 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.

    2. 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.

    3. 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.

    4. Interpretation neutrality in the classical domain of quantum theory

      NASA Astrophysics Data System (ADS)

      Rosaler, Joshua

      2016-02-01

      I show explicitly how concerns about wave function collapse and ontology can be decoupled from the bulk of technical analysis necessary to recover localized, approximately Newtonian trajectories from quantum theory. In doing so, I demonstrate that the account of classical behavior provided by decoherence theory can be straightforwardly tailored to give accounts of classical behavior on multiple interpretations of quantum theory, including the Everett, de Broglie-Bohm and GRW interpretations. I further show that this interpretation-neutral, decoherence-based account conforms to a general view of inter-theoretic reduction in physics that I have elaborated elsewhere, which differs from the oversimplified picture that treats reduction as a matter of simply taking limits. This interpretation-neutral account rests on a general three-pronged strategy for reduction between quantum and classical theories that combines decoherence, an appropriate form of Ehrenfest's Theorem, and a decoherence-compatible mechanism for collapse. It also incorporates a novel argument as to why branch-relative trajectories should be approximately Newtonian, which is based on a little-discussed extension of Ehrenfest's Theorem to open systems, rather than on the more commonly cited but less germane closed-systems version. In the Conclusion, I briefly suggest how the strategy for quantum-classical reduction described here might be extended to reduction between other classical and quantum theories, including classical and quantum field theory and classical and quantum gravity.

    5. Classical theory of atomic collisions - The first hundred years

      NASA Astrophysics Data System (ADS)

      Grujić, Petar V.

      2012-05-01

      Classical calculations of the atomic processes started in 1911 with famous Rutherford's evaluation of the differential cross section for α particles scattered on foil atoms [1]. The success of these calculations was soon overshadowed by the rise of Quantum Mechanics in 1925 and its triumphal success in describing processes at the atomic and subatomic levels. It was generally recognized that the classical approach should be inadequate and it was neglected until 1953, when the famous paper by Gregory Wannier appeared, in which the threshold law for the single ionization cross section behaviour by electron impact was derived. All later calculations and experimental studies confirmed the law derived by purely classical theory. The next step was taken by Ian Percival and collaborators in 60s, who developed a general classical three-body computer code, which was used by many researchers in evaluating various atomic processes like ionization, excitation, detachment, dissociation, etc. Another approach was pursued by Michal Gryzinski from Warsaw, who started a far reaching programme for treating atomic particles and processes as purely classical objects [2]. Though often criticized for overestimating the domain of the classical theory, results of his group were able to match many experimental data. Belgrade group was pursuing the classical approach using both analytical and numerical calculations, studying a number of atomic collisions, in particular near-threshold processes. Riga group, lead by Modris Gailitis [3], contributed considerably to the field, as it was done by Valentin Ostrovsky and coworkers from Sanct Petersbourg, who developed powerful analytical methods within purely classical mechanics [4]. We shall make an overview of these approaches and show some of the remarkable results, which were subsequently confirmed by semiclassical and quantum mechanical calculations, as well as by the experimental evidence. Finally we discuss the theoretical and

    6. Classical irregular block, = 2 pure gauge theory and Mathieu equation

      NASA Astrophysics Data System (ADS)

      Piątek, Marcin; Pietrykowski, Artur R.

      2014-12-01

      Combining the semiclassical/Nekrasov-Shatashvili limit of the AGT conjecture and the Bethe/gauge correspondence results in a triple correspondence which identifies classical conformal blocks with twisted superpotentials and then with Yang-Yang functions. In this paper the triple correspondence is studied in the simplest, yet not completely understood case of pure SU(2) super-Yang-Mills gauge theory. A missing element of that correspondence is identified with the classical irregular block. Explicit tests provide a convincing evidence that such a function exists. In particular, it has been shown that the classical irregular block can be recovered from classical blocks on the torus and sphere in suitably defined decoupling limits of classical external conformal weights. These limits are "classical analogues" of known decoupling limits for corresponding quantum blocks. An exact correspondence between the classical irregular block and the SU(2) gauge theory twisted superpotential has been obtained as a result of another consistency check. The latter determines the spectrum of the 2-particle periodic Toda (sin-Gordon) Hamiltonian in accord with the Bethe/gauge correspondence. An analogue of this statement is found entirely within 2 d CFT. Namely, considering the classical limit of the null vector decoupling equation for the degenerate irregular block a celebrated Mathieu's equation is obtained with an eigenvalue determined by the classical irregular block. As it has been checked this result reproduces a well known weak coupling expansion of Mathieu's eigenvalue. Finally, yet another new formulae for Mathieu's eigenvalue relating the latter to a solution of certain Bethe-like equation are found.

    7. Nephritic Factor of the Classical Pathway of Complement

      PubMed Central

      Halbwachs, L.; Leveillé, M.; Lesavre, Ph.; Wattel, S.; Leibowitch, J.

      1980-01-01

      A factor, functionally characterized by its capacity to stabilize the normally labile classical pathway C3-converting complex of the classical pathway of complement, has been isolated from the serum of one patient with a case of acute glomerulonephritis, subsequent to a cutaneous infection. The factor confers long-lived stabilization of classical pathway C3 convertase complexes formed both in the solid (sensitized sheep erythrocytes bearing activated C̄1̄ and the classical pathway C3 convertase) and fluid phase. The half-life of such stabilized C3-cleaving enzymes extended beyond several hours at 37°C. The stabilizing activity was associated with a protein fraction immunochemically identified as immunoglobulin (Ig)G, a sizeable population of which exhibited a gamma chain of 60,000 daltons. The IgG-associated stabilizing activity was found to bind to the classical pathway C3 convertase enzyme via a fragment bearing the antigen-binding site of the molecule [F(ab)2 and F(ab)]. Such binding was demonstrable for classical pathway and not for alternative pathway C3 convertase. Thus, the stabilizing factor behaves like an autoantibody to the C3-converting complex of the classical pathway of complement. The binding of the antibody to the enzyme affords protection of the latter against decay-degradation. By analogy with the nephritic factor of the alternative pathway situation where IgG autoantibodies specifically bind to alternative pathway C3 convertase enzymes and protect them from degradation, the functionally unusual IgG in our patient was designated as the nephritic factor of the classical pathway. Indirect evidence suggests that nephritic factor of the classical pathway-IgG might be of the IgG3 subclass. Images PMID:6902727

    8. 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.

    9. Classical singularities in chaotic atom-surface scattering

      SciTech Connect

      Miret-Artes, S.; Margalef-Roig, J.; Guantes, R.; Borondo, F.; Jaffe, C.

      1996-10-01

      In this paper we show that the diffraction condition for the scattering of atoms from surfaces leads to the appearance of a distinct type of classical singularity. Moreover, it is also shown that the onset of classical trapping or classical chaos is closely related to the bifurcation set of the diffraction-order function around the surface points presenting the rainbow effect. As an illustration of this dynamic, application to the scattering of He atoms by the stepped Cu(115) surface is presented using both a hard corrugated one-dimensional wall and a soft corrugated Morse potential. {copyright} {ital 1996 The American Physical Society.}

    10. 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.

    11. Quantized Eigenstates of a Classical Particle in a Ponderomotive Potential

      SciTech Connect

      I.Y. Dodin; N.J. Fisch

      2004-12-21

      The average dynamics of a classical particle under the action of a high-frequency radiation resembles quantum particle motion in a conservative field with an effective de Broglie wavelength ë equal to the particle average displacement on a period of oscillations. In a "quasi-classical" field, with a spatial scale large compared to ë, the guiding center motion is adiabatic. Otherwise, a particle exhibits quantized eigenstates in a ponderomotive potential well, can tunnel through classically forbidden regions and experience reflection from an attractive potential. Discrete energy levels are also found for a "crystal" formed by multiple ponderomotive barriers.

    12. 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.

    13. 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. PMID:27391707

    14. Classical string dynamics with non-trivial topology

      NASA Astrophysics Data System (ADS)

      Deck, Thomas

      1995-04-01

      The possibility of branching processes for classical strings is investigated on the basis of the Nambu-Goto action. We parametrize the world sheet by a Riemann surface M and introduce a degenerate, semi-Riemannian metric η on M. Well-known results about the conformal group Diff( S1) × Diff( S1) are generalized to the case of ( M, η). We provide an infinite dimensional Hamiltonian setting for branching processes of strings. Finally, the classical background for the theory of quantum strings as developed by Krichever and Novikov is discussed within this classical framework.

    15. The structure of classical extensions of quantum probability theory

      NASA Astrophysics Data System (ADS)

      Stulpe, Werner; Busch, Paul

      2008-03-01

      On the basis of a suggestive definition of a classical extension of quantum mechanics in terms of statistical models, we prove that every such classical extension is essentially given by the so-called Misra-Bugajski reduction map. We consider how this map enables one to understand quantum mechanics as a reduced classical statistical theory on the projective Hilbert space as phase space and discuss features of the induced hidden-variable model. Moreover, some relevant technical results on the topology and Borel structure of the projective Hilbert space are reviewed.

    16. Classical Physics and the Bounds of Quantum Correlations

      NASA Astrophysics Data System (ADS)

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

      2016-06-01

      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.

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

      PubMed

      Hooft, Gerard 't

      2015-08-01

      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. PMID:26124246

    18. 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.

    19. Arbiter as the Third Man in Classical and Quantum Games

      NASA Astrophysics Data System (ADS)

      Pykacz, Jarosław; FraÇkiewicz, Piotr

      2010-12-01

      We study the possible influence of a not necessarily sincere arbiter on the course of classical and quantum 2×2 games and we show that this influence in the quantum case is much bigger than in the classical case. Extreme sensitivity of quantum games on initial states of quantum objects used as carriers of information in a game shows that a quantum game, contrary to a classical game, is not defined by a payoff matrix alone but also by an initial state of objects used to play a game. Therefore, two quantum games that have the same payoff matrices but begin with different initial states should be considered as different games.

    20. 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

      1. 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

      2. 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)

      3. 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)

      4. Renyi entropies for classical string-net models

        NASA Astrophysics Data System (ADS)

        Hermanns, M.; Trebst, S.

        2014-05-01

        In quantum mechanics, string-net condensed states—a family of prototypical states exhibiting nontrivial topological order—can be classified via their long-range entanglement properties, in particular, topological corrections to the prevalent area law of the entanglement entropy. Here we consider classical analogs of such string-net models whose partition function is given by an equal-weight superposition of classical string-net configurations. Our analysis of the Shannon and Renyi entropies for a bipartition of a given system reveals that the prevalent volume law for these classical entropies is augmented by subleading topological corrections that are intimately linked to the anyonic theories underlying the construction of the classical models. We determine the universal values of these topological corrections for a number of underlying anyonic theories including SU(2)k,SU(N)1, and SU(N)2 theories.

      5. Classical cutoffs for laser-induced nonsequential double ionization

        SciTech Connect

        Milosevic, D.B.; Becker, W.

        2003-12-01

        Classical cutoffs for the momenta of electrons ejected in laser-induced nonsequential double ionization are derived for the recollision-impact-ionization scenario. Such simple cutoff laws can aid in the interpretation of the observed electron spectra.

      6. Seven Galactic classical novae from the OGLE-IV Survey

        NASA Astrophysics Data System (ADS)

        Mroz, P.; Udalski, A.

        2016-07-01

        We report the discovery of seven classical novae located in the Galactic bulge and disk fields. Novae were found during a search for bright transients in data from the OGLE-IV sky survey from observing seasons 2014-2016.

      7. Bennett: Colleges'"Trendy Lightweights" Replace Classics with Nonsense.

        ERIC Educational Resources Information Center

        Wilson, Robin

        1988-01-01

        The Secretary of Education recently claimed that the American public is losing faith in colleges and universities because faculty are removing classic works from the curriculum and replacing them with watered-down offerings, drawing criticism from campus administrators. (MSE)

      8. 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)

      9. Maximal Parrondo's Paradox for Classical and Quantum Markov Chains

        NASA Astrophysics Data System (ADS)

        Grünbaum, F. Alberto; Pejic, Michael

        2016-02-01

        Parrondo's paradox refers to the situation where two, multi-round games with a fixed winning criteria, both with probability greater than one-half for one player to win, are combined. Using a possibly biased coin to determine the rule to employ for each round, paradoxically, the previously losing player now wins the combined game with probability greater than one-half. In this paper, we will analyze classical observed, classical hidden, and quantum versions of a game that displays this paradox. The game we have utilized is simpler than games for which this behavior has been previously noted in the classical and quantum cases. We will show that in certain situations the paradox can occur to a greater degree in the quantum version than is possible in the classical versions.

      10. Classical and quantum mechanical motion in magnetic fields

        NASA Astrophysics Data System (ADS)

        Franklin, J.; Cole Newton, K.

        2016-04-01

        We study the motion of a particle in a particular magnetic field configuration both classically and quantum mechanically. For flux-free radially symmetric magnetic fields defined on circular regions, we establish that particle escape speeds depend, classically, on a gauge-fixed magnetic vector potential, and we demonstrate some trajectories associated with this special type of magnetic field. Then we show that some of the geometric features of the classical trajectory (perpendicular exit from the field region, trapped and escape behavior) are reproduced quantum mechanically, using a numerical method that extends the norm-preserving Crank-Nicolson method to problems involving magnetic fields. While there are similarities between the classical trajectory and the position expectation value of the quantum-mechanical solution, there are also differences, and we demonstrate some of these.

      11. Classical and Quantum Mechanical Motion in Magnetic Fields

        NASA Astrophysics Data System (ADS)

        Newton, K. Cole; Franklin, Joel

        2016-03-01

        We study the motion of a particle in a particular magnetic field configuration both classically and quantum mechanically. For flux-free radially symmetric magnetic fields defined on circular regions, we establish that particle escape speeds depend, classically, on a gauge-fixed magnetic vector potential, and demonstrate some trajectories associated with this special type of magnetic field. Then we show that some of the geometric features of the classical trajectory (perpendicular exit from the field region, trapped and escape behavior) are reproduced quantum mechanically using a numerical method that extends the norm-preserving Crank-Nicolson method to problems involving magnetic fields. While there are similarities between the classical trajectory and the position expectation value of the quantum mechanical solution, there are also differences, and we demonstrate some of these.

      12. A Classical Calculation of the Leptonic Magnetic Moment

        NASA Astrophysics Data System (ADS)

        Fabbri, Luca

        2016-02-01

        In this paper we will show that purely classical concepts based on a few heuristic considerations about extended field configurations are enough to compute the leptonic magnetic moment with corrections in α-power perturbative expansion.

      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. 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)

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

        PubMed

        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

      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. Visualizing the semantic structure in classical music works.

        PubMed

        Chan, Wing-Yi; Qu, Huamin; Mak, Wai-Ho

        2010-01-01

        A major obstacle in the appreciation of classical music is that extensive training is required to understand musical structure and compositional techniques toward comprehending the thoughts behind the musical work. In this paper, we propose an innovative visualization solution to reveal the semantic structure in classical orchestral works such that users can gain insights into musical structure and appreciate the beauty of music. We formulate the semantic structure into macrolevel layer interactions, microlevel theme variations, and macro-micro relationships between themes and layers to abstract the complicated construction of a musical composition. The visualization has been applied with success in understanding some classical music works as supported by highly promising user study results with the general audience and very positive feedback from music students and experts, demonstrating its effectiveness in conveying the sophistication and beauty of classical music to novice users with informative and intuitive displays. PMID:19910669

      18. Information flow during the quantum-classical transition

        NASA Astrophysics Data System (ADS)

        Kowalski, A. M.; Martin, M. T.; Plastino, A.; Zunino, L.

        2010-04-01

        We have exhaustively investigated the classical limit of the semi-classical evolution with reference to a well-known model that represents the interaction between matter and a given field. In this Letter we approach this issue by recourse to a new statistical quantifier called the “symbolic transfer entropy” [T. Schreiber, Phys. Rev. Lett. 85 (2000) 461; M. Staniek, K. Lehnertz, Phys. Rev. Lett. 100 (2008) 158101]. We encounter that the quantum-classical transition gets thereby described as the sign reversal of the dominating direction of the information flow between classical and quantal variables. This can be considered as an evidence of the physical useful of this new statistical quantifier.

      19. 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.

      20. 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)

      1. 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.

      2. Improving Zero-Error Classical Communication with Entanglement

        NASA Astrophysics Data System (ADS)

        Cubitt, Toby S.; Leung, Debbie; Matthews, William; Winter, Andreas

        2010-06-01

        Given one or more uses of a classical channel, only a certain number of messages can be transmitted with zero probability of error. The study of this number and its asymptotic behavior constitutes the field of classical zero-error information theory. We show that, given a single use of certain classical channels, entangled states of a system shared by the sender and receiver can be used to increase the number of (classical) messages which can be sent without error. In particular, we show how to construct such a channel based on any proof of the Kochen-Specker theorem. We investigate the connection to pseudotelepathy games. The use of generalized nonsignaling correlations to assist in this task is also considered. In this case, an elegant theory results and, remarkably, it is sometimes possible to transmit information with zero error using a channel with no unassisted zero-error capacity.

      3. 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…

      4. 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.

      5. Classic metaphyseal lesion following external cephalic version and cesarean section.

        PubMed

        Lysack, John T; Soboleski, Don

        2003-06-01

        We report a case of an otherwise healthy neonate diagnosed at birth with a classic metaphyseal lesion of the proximal tibia following external cephalic version for frank breech presentation and a subsequent urgent cesarean section. Although the classic metaphyseal lesion is considered highly specific for infant abuse, this case demonstrates the importance of obtaining a history of obstetric trauma for neonates presenting to the imaging department for suspected non-accidental injury. PMID:12709748

      6. 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.

      7. The Semantic Structure of Neo-Classical Compounds

        PubMed Central

        McCray, Alexa T.; Browne, Allen C.; Moore, Dorothy L.

        1988-01-01

        The automated analysis of neo-classical compounds in the medical domain has been proposed and carried out by a number of researchers in recent years. This paper discusses the semantics of these compounds. The results of our work indicate that neo-classical compounds are semantically underdetermined by their constituent parts. Thus, automated analysis of these compounds will need to be supplemented by human review.

      8. 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

      9. 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. PMID:15638649

      10. Geodesics in information geometry: classical and quantum phase transitions.

        PubMed

        Kumar, Prashant; Mahapatra, Subhash; Phukon, Prabwal; Sarkar, Tapobrata

        2012-11-01

        We study geodesics on the parameter manifold for systems exhibiting second order classical and quantum phase transitions. The coupled nonlinear geodesic equations are solved numerically for a variety of models which show such phase transitions in the thermodynamic limit. It is established that both in the classical as well as in the quantum cases, geodesics are confined to a single phase and exhibit turning behavior near critical points. Our results are indicative of a geometric universality in widely different physical systems. PMID:23214748

      11. Trigonometric version of quantum-classical duality in integrable systems

        NASA Astrophysics Data System (ADS)

        Beketov, M.; Liashyk, A.; Zabrodin, A.; Zotov, A.

        2016-02-01

        We extend the quantum-classical duality to the trigonometric (hyperbolic) case. The duality establishes an explicit relationship between the classical N-body trigonometric Ruijsenaars-Schneider model and the inhomogeneous twisted XXZ spin chain on N sites. Similarly to the rational version, the spin chain data fixes a certain Lagrangian submanifold in the phase space of the classical integrable system. The inhomogeneity parameters are equal to the coordinates of particles while the velocities of classical particles are proportional to the eigenvalues of the spin chain Hamiltonians (residues of the properly normalized transfer matrix). In the rational version of the duality, the action variables of the Ruijsenaars-Schneider model are equal to the twist parameters with some multiplicities defined by quantum (occupation) numbers. In contrast to the rational version, in the trigonometric case there is a splitting of the spectrum of action variables (eigenvalues of the classical Lax matrix). The limit corresponding to the classical Calogero-Sutherland system and quantum trigonometric Gaudin model is also described as well as the XX limit to free fermions.

      12. Modeling the quantum evolution of the universe through classical matter

        NASA Astrophysics Data System (ADS)

        Pitelli, João Paulo M.; Letelier, Patricio S.

        2013-07-01

        It is well known that the canonical quantization of the Friedmann-Lemaître-Robertson-Walker (FLRW) filled with a perfect fluid leads to nonsingular universes which, for later times, behave as their classical counterpart. This means that the expectation value of the scale factor (t) never vanishes and, as t→ infty , we recover the classical expression for the scale factor. In this paper, we show that such universes can be reproduced by classical cosmology given that the universe is filled with an exotic matter. In the case of a perfect fluid, we find an implicit equation of state (EoS). We then show that this single fluid with an implict EoS is equivalent to two non-interacting fluids, one of them representing stiff matter with negative energy density. In the case of two non-interacting scalar fields, one of them of the phantom type, we find their potential energy. In both cases we find that quantum mechanics changes completely the configuration of matter for small values of time, by adding a fluid or a scalar field with negative energy density. As time passes, the density of negative energy decreases and we recover the ordinary content of the classical universe. The more the initial wave function of the universe is concentrated around the classical big bang singularity, the more it is necessary to add negative energy, since this type of energy will be responsible for the removal of the classical singularity.

      13. Can fluctuations of classical random field produce quantum averages?

        NASA Astrophysics Data System (ADS)

        Khrennikov, Andrei

        2009-08-01

        Albert Einstein did not believe in completeness of QM. He dreamed of creation of prequantum classical statistical mechanics such that QM will be reproduced as its approximation. He also dreamed of total exclusion of corpuscules from the future model. Reality of Einstein's dream was pure fields' reality. Recently I made his dream come true in the form of so called prequantum classical statistical field theory (PCSFT). In this approach quantum systems are described by classical random fields, e.g., electromagnetic field (instead of photon), electron field or neutron field. In this paper we generalize PCSFT to composite quantum system. It is well known that in QM, unlike classical mechanics, the state of a composite system is described by the tensor product of state spaces for its subsystems. In PCSFT one can still use Cartesian product, but state spaces are spaces of classical fields (not particles). In particular, entanglement is nothing else than correlation of classical random fields, cf. again Einstein. Thus entanglement was finally demystified.

      14. Opening up three quantum boxes causes classically undetectable wavefunction collapse

        PubMed Central

        George, Richard E.; Robledo, Lucio M.; Maroney, Owen J. E.; Blok, Machiel S.; Bernien, Hannes; Markham, Matthew L.; Twitchen, Daniel J.; Morton, John J. L.; Briggs, G. Andrew D.; Hanson, Ronald

        2013-01-01

        One of the most striking features of quantum mechanics is the profound effect exerted by measurements alone. Sophisticated quantum control is now available in several experimental systems, exposing discrepancies between quantum and classical mechanics whenever measurement induces disturbance of the interrogated system. In practice, such discrepancies may frequently be explained as the back-action required by quantum mechanics adding quantum noise to a classical signal. Here, we implement the “three-box” quantum game [Aharonov Y, et al. (1991) J Phys A Math Gen 24(10):2315–2328] by using state-of-the-art control and measurement of the nitrogen vacancy center in diamond. In this protocol, the back-action of quantum measurements adds no detectable disturbance to the classical description of the game. Quantum and classical mechanics then make contradictory predictions for the same experimental procedure; however, classical observers are unable to invoke measurement-induced disturbance to explain the discrepancy. We quantify the residual disturbance of our measurements and obtain data that rule out any classical model by ≳7.8 standard deviations, allowing us to exclude the property of macroscopic state definiteness from our system. Our experiment is then equivalent to the test of quantum noncontextuality [Kochen S, Specker E (1967) J Math Mech 17(1):59–87] that successfully addresses the measurement detectability loophole. PMID:23412336

      15. [Today's meaning of classical authors of political thinking].

        PubMed

        Weinacht, Paul-Ludwig

        2005-01-01

        How can classical political authors be actualised? The question is asked in a discipline which is founded in old traditions: the political science. One of its great matters is the history of political ideas. Classic authors are treated in many books, but they are viewed in different perspectives; colleagues do not agree with shining and bad examples. For actualising classic we have to go a methodically reflected way: historic not historicistic, with sensibility for classic and christian norms without dogmatism or scepticism. Searching the permanent problems we try to translate the original concepts of the classic authors carefully in our time. For demonstrating our method of actualising, we choose the French classical author Montesquieu. His famous concept of division of powers is misunderstood as a "liberal" mechanism which works in itself in favour of freedom (such as Kant made work a "natural mechanism" in a people of devils in favour of their legality); in reality Montesquieu acknoledges that constitutional und organisational work cannot stabilise themselves but must be found in social character and in human virtues. PMID:17153317

      16. Relativistic wave and particle mechanics formulated without classical mass

        SciTech Connect

        Fry, J.L.; Musielak, Z.E.; Chang, Trei-wen

        2011-08-15

        Highlights: > Formal derivation of the Klein-Gordon equation with an invariant frequency. > Formal derivation of the relativistic version of Newton's equation. > The classical mass is replaced by the invariant frequency. > The invariant frequencies for selected elementary particles are deduced. > The choice of natural units resulting from the developed theories is discussed. - Abstract: The fact that the concept of classical mass plays an important role in formulating relativistic theories of waves and particles is well-known. However, recent studies show that Galilean invariant theories of waves and particles can be formulated with the so-called 'wave mass', which replaces the classical mass and allows attaining higher accuracy of performing calculations [J.L. Fry and Z.E. Musielak, Ann. Phys. 325 (2010) 1194]. The main purpose of this paper is to generalize these results and formulate fundamental (Poincare invariant) relativistic theories of waves and particles without the classical mass. In the presented approach, the classical mass is replaced by an invariant frequency that only involves units of time. The invariant frequencies for various elementary particles are deduced from experiments and their relationship to the corresponding classical and wave mass for each particle is described. It is shown that relativistic wave mechanics with the invariant frequency is independent of the Planck constant, and that such theory can attain higher accuracy of performing calculations. The choice of natural units resulting from the developed theories of waves and particles is also discussed.

      17. Rotation of classical bulges during secular evolution of barred galaxies

        NASA Astrophysics Data System (ADS)

        Saha, Kanak; Gerhard, Ortwin

        2015-03-01

        Bar driven secular evolution plays a key role in changing the morphology and kinematics of disk galaxies, leading to the formation of rapidly rotating boxy/peanut bulges. If these disk galaxies also hosted a preexisting classical bulge, how would the secular evolution influence the classical bulge, and also the observational properties. We first study the co-evolution of a bar and a preexisting non-rotating low-mass classical bulge such as might be present in galaxies like the Milky Way. It is shown with N-body simulations that during the secular evolution, such a bulge can gain significant angular momentum emitted by the bar through resonant and stochastic orbits. Thereby it transforms into a cylindrically rotating, anisotropic and triaxial object, embedded in the fast rotating boxy bulge that forms via disk instability (Saha et al. 2012). The composite boxy/peanut bulge also rotates cylindrically. We then show that the growth of the bar depends only slightly on the rotation properties of the preexisting classical bulge. For the initially rotating small classical bulge, cylindrical rotation in the resulting composite boxy/peanut bulge extends to lower heights (Saha & Gerhard 2013). More massive classical bulges also gain angular momentum emitted by the bar, inducing surprisingly large rotational support within about 4 Gyrs (Saha et al. in prep).

      18. Classical and quantum correlative capacities of quantum systems

        SciTech Connect

        Li Nan; Luo Shunlong

        2011-10-15

        How strongly can one system be correlated with another? In the classical world, this basic question concerning correlative capacity has a very satisfying answer: The ''effective size'' of the marginal system, as quantified by the Shannon entropy, sets a tight upper bound to the correlations, as quantified by the mutual information. Although in the quantum world bipartite correlations, like their classical counterparts, are also well quantified by mutual information, the similarity ends here: The correlations in a bipartite quantum system can be twice as large as the marginal entropy. In the paradigm of quantum discord, the correlations are split into classical and quantum components, and it was conjectured that both the classical and quantum correlations are (like the classical mutual information) bounded above by each subsystem's entropy. In this work, by exploiting the interplay between entanglement of formation, mutual information, and quantum discord, we disprove that conjecture. We further indicate a scheme to restore harmony between quantum and classical correlative capacities. The results illustrate dramatically the asymmetric nature of quantum discord and highlight some subtle and unusual features of quantum correlations.

      19. CLASSICAL TRAJECTORY MODELS FOR ELECTRONICALLY NON-ADIABATIC COLLISION PROCESSES: A CLASSICAL VALENCE BOND MODEL FOR ELECTRONIC DEGREES OF FREEDOM

        SciTech Connect

        Miller, William H.; Orel, Ann E.

        1980-11-01

        A classical interpretation of the Dirac-Van Vleck spin version of valence bond theory is used 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-H{sub 2}, F-H{sub 2} , and O-H{sub 2} 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. The attractive feature of this model is that it is as eaaily applicable to electronically non-adiabatic processes as it is to adiabatic ones.

      20. A critical experimental study of the classical tactile threshold theory

        PubMed Central

        2010-01-01

        Background The tactile sense is being used in a variety of applications involving tactile human-machine interfaces. In a significant number of publications the classical threshold concept plays a central role in modelling and explaining psychophysical experimental results such as in stochastic resonance (SR) phenomena. In SR, noise enhances detection of sub-threshold stimuli and the phenomenon is explained stating that the required amplitude to exceed the sensory threshold barrier can be reached by adding noise to a sub-threshold stimulus. We designed an experiment to test the validity of the classical vibrotactile threshold. Using a second choice experiment, we show that individuals can order sensorial events below the level known as the classical threshold. If the observer's sensorial system is not activated by stimuli below the threshold, then a second choice could not be above the chance level. Nevertheless, our experimental results are above that chance level contradicting the definition of the classical tactile threshold. Results We performed a three alternative forced choice detection experiment on 6 subjects asking them first and second choices. In each trial, only one of the intervals contained a stimulus and the others contained only noise. According to the classical threshold assumptions, a correct second choice response corresponds to a guess attempt with a statistical frequency of 50%. Results show an average of 67.35% (STD = 1.41%) for the second choice response that is not explained by the classical threshold definition. Additionally, for low stimulus amplitudes, second choice correct detection is above chance level for any detectability level. Conclusions Using a second choice experiment, we show that individuals can order sensorial events below the level known as a classical threshold. If the observer's sensorial system is not activated by stimuli below the threshold, then a second choice could not be above the chance level. Nevertheless, our

      1. Classical Morphology of Plants as an Elementary Instance of Classical Invariant Theory

        PubMed Central

        Mavrodiev, Evgeny V.

        2009-01-01

        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. PMID:19759908

      2. Making classical ground-state spin computing fault-tolerant.

        PubMed

        Crosson, I J; Bacon, D; Brown, K R

        2010-09-01

        We examine a model of classical deterministic computing in which the ground state of the classical system is a spatial history of the computation. This model is relevant to quantum dot cellular automata as well as to recent universal adiabatic quantum computing constructions. In its most primitive form, systems constructed in this model cannot compute in an error-free manner when working at nonzero temperature. However, by exploiting a mapping between the partition function for this model and probabilistic classical circuits we are able to show that it is possible to make this model effectively error-free. We achieve this by using techniques in fault-tolerant classical computing and the result is that the system can compute effectively error-free if the temperature is below a critical temperature. We further link this model to computational complexity and show that a certain problem concerning finite temperature classical spin systems is complete for the complexity class Merlin-Arthur. This provides an interesting connection between the physical behavior of certain many-body spin systems and computational complexity. PMID:21230024

      3. Classical universes of the no-boundary quantum state

        NASA Astrophysics Data System (ADS)

        Hartle, James B.; Hawking, S. W.; Hertog, Thomas

        2008-06-01

        We analyze the origin of the quasiclassical realm from the no-boundary proposal for the Universe’s quantum state in a class of minisuperspace models. The models assume homogeneous, isotropic, closed spacetime geometries, a single scalar field moving in a quadratic potential, and a fundamental cosmological constant. The allowed classical histories and their probabilities are calculated to leading semiclassical order. For the most realistic range of parameters analyzed, we find that a minimum amount of scalar field is required, if there is any at all, in order for the Universe to behave classically at late times. If the classical late time histories are extended back, they may be singular or bounce at a finite radius. The ensemble of classical histories is time symmetric although individual histories are generally not. The no-boundary proposal selects inflationary histories, but the measure on the classical solutions it provides is heavily biased towards small amounts of inflation. However, the probability for a large number of e-foldings is enhanced by the volume factor needed to obtain the probability for what we observe in our past light cone, given our present age. Our results emphasize that it is the quantum state of the Universe that determines whether or not it exhibits a quasiclassical realm and what histories are possible or probable within that realm.

      4. Classical versus quantum errors in quantum computation of dynamical systems.

        PubMed

        Rossini, Davide; Benenti, Giuliano; Casati, Giulio

        2004-11-01

        We analyze the stability of a quantum algorithm simulating the quantum dynamics of a system with different regimes, ranging from global chaos to integrability. We compare, in these different regimes, the behavior of the fidelity of quantum motion when the system's parameters are perturbed or when there are unitary errors in the quantum gates implementing the quantum algorithm. While the first kind of errors has a classical limit, the second one has no classical analog. It is shown that, whereas in the first case ("classical errors") the decay of fidelity is very sensitive to the dynamical regime, in the second case ("quantum errors") it is almost independent of the dynamical behavior of the simulated system. Therefore, the rich variety of behaviors found in the study of the stability of quantum motion under "classical" perturbations has no correspondence in the fidelity of quantum computation under its natural perturbations. In particular, in this latter case it is not possible to recover the semiclassical regime in which the fidelity decays with a rate given by the classical Lyapunov exponent. PMID:15600737

      5. Coexistence of continuous variable QKD with intense DWDM classical channels

        NASA Astrophysics Data System (ADS)

        Kumar, Rupesh; Qin, Hao; Alléaume, Romain

        2015-04-01

        We demonstrate experimentally the feasibility of continuous variable quantum key distribution (CV-QKD) in dense-wavelength-division multiplexing networks (DWDM), where QKD will typically have to coexist with several co-propagating (forward or backward) C-band classical channels whose launch power is around 0 dBm. We have conducted experimental tests of the coexistence of CV-QKD multiplexed with an intense classical channel, for different input powers and different DWDM wavelengths. Over a 25 km fiber, a CV-QKD operated over the 1530.12 nm channel can tolerate the noise arising from up to 11.5 dBm classical channel at 1550.12 nm in the forward direction (9.7 dBm in backward). A positive key rate (0.49 kbits s-1) can be obtained at 75 km with classical channel power of respectively -3 and -9 dBm in forward and backward. Based on these measurements, we have also simulated the excess noise and optimized channel allocation for the integration of CV-QKD in some access networks. We have, for example, shown that CV-QKD could coexist with five pairs of channels (with nominal input powers: 2 dBm forward and 1 dBm backward) over a 25 km WDM-PON network. The obtained results demonstrate the outstanding capacity of CV-QKD to coexist with classical signals of realistic intensity in optical networks.

      6. Communication Tasks with Infinite Quantum-Classical Separation.

        PubMed

        Perry, Christopher; Jain, Rahul; Oppenheim, Jonathan

        2015-07-17

        Quantum resources can be more powerful than classical resources-a quantum computer can solve certain problems exponentially faster than a classical computer, and computing a function of two parties' inputs can be done with exponentially less communication with quantum messages than with classical ones. Here we consider a task between two players, Alice and Bob where quantum resources are infinitely more powerful than their classical counterpart. Alice is given a string of length n, and Bob's task is to exclude certain combinations of bits that Alice might have. If Alice must send classical messages, then she must reveal nearly n bits of information to Bob, but if she is allowed to send quantum bits, the amount of information she must reveal goes to zero with increasing n. Next, we consider a version of the task where the parties may have access to entanglement. With this assistance, Alice only needs to send a constant number of bits, while without entanglement, the number of bits Alice must send grows linearly with n. The task is related to the Pusey-Barrett-Rudolph theorem which arises in the context of the foundations of quantum theory. PMID:26230777

      7. Quantum analogues of classical wakes in Bose-Einstein condensates

        NASA Astrophysics Data System (ADS)

        Stagg, George; Parker, Nick; Barenghi, Carlo

        2014-11-01

        We show that an elliptical obstacle moving through a Bose-Einstein condensate generates wakes of quantum vortices which resemble those of classical viscous flow past a cylinder or sphere. Initial steady symmetric wakes, similar to those observed in classical flow at low Reynolds number, lose their symmetry and form clusters of like-signed vortices, in analogy to the classical Bénard-von Kármán vortex street. The key ingredient to produce classical-like wakes is that vortices are generated at a sufficiently high rate that they undergo strong interactions with their neighbours (rather than being swept away). The role of ellipticity is to facilitate the interaction of the vortices and to reduce the critical velocity for vortex nucleation. Our findings, demonstrated numerically in both two and three dimensions, confirm the intuition that a sufficiently large number of quanta of circulation reproduce classical physics. The effects which we describe (dependence of the critical velocity and cluster size on the obstacle's size, velocity and ellipticity) are also relevant to the motion of objects (such as vibrating wires, grids and forks) in superfluid helium, as the obstacle's ellipticity plays a role which is analogous to rough boundaries.

      8. 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.

      9. Involvement of Antilipoarabinomannan Antibodies in Classical Complement Activation in Tuberculosis

        PubMed Central

        Hetland, Geir; Wiker, Harald G.; Høgåsen, Kolbjørn; Hamasur, Beston; Svenson, Stefan B.; Harboe, Morten

        1998-01-01

        We examined alternative and classical complement activation induced by whole bacilli of Mycobacterium bovis BCG and Mycobacterium tuberculosis products. After exposure to BCG, there were higher levels of the terminal complement complex in sera from Indian tuberculosis patients than in sera from healthy controls. The addition of BCG with or without EGTA to these sera indicated that approximately 70 to 85% of the total levels of the terminal complement complex was formed by classical activation. Sera from Indian tuberculosis patients contained more antibody to lipoarabinomannan (LAM) than sera from healthy Indians. Levels of anti-LAM immunoglobulin G2 (IgG2), but not anti-LAM IgM, correlated positively with classical activation induced by BCG in the sera. By flow cytometry, deposition of C3 and terminal complement complex on bacilli incubated with normal human serum was demonstrated. The anticomplement staining was significantly reduced in the presence of EGTA and EDTA. Flow cytometry also revealed the binding of complement to BCG incubated with rabbit anti-LAM and then with factor B-depleted serum. This indicates that classical activation plays a major role in complement activation induced by mycobacteria and that anti-LAM IgG on the bacilli can mediate this response. Classical complement activation may be important for the extent of phagocytosis of M. tuberculosis by mononuclear phagocytes, which may influence the course after infection. PMID:9521145

      10. 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).

      11. Revisited Study On The Survival Regions Of Classical Kbos

        NASA Astrophysics Data System (ADS)

        Da Silva Gaspar, Helton; Nesvorný, D.; Morbidelli, A.

        2012-10-01

        Many studies has been dedicated to explain the complex Kuiper Belt structure. In a recent study, Dawson & Murray-Clay (2012) propose an assembly model that forms hot classical KBOs interior to Neptune and delivers them to the classical region where the cold populations forms in-situ. By using the survival map by Lykawka & Mukay (2005), their theory is supported by the absence of objects inside a stable region in the space of initial semimajor axis versus eccentricity. They argue that such region should contain excited in-situ original objects. We reproduce the 4Gy survival map but in terms of propers semimajor, eccentricity and inclination instead. By superimposing the classical KBOs over our survival map, we find out that cold objects cover uniformly the whole survival region. This result agrees with a scenario in which in-situ nearly circular objects had eccentricities excited then yielding an uniform distribution all over the survival region.

      12. Properties of the Boltzmann equation in the classical approximation

        DOE PAGESBeta

        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 onemore » has also access to the non-approximated result for comparison.« less

      13. 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.

      14. 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.

      15. Universality of level spacing distributions in classical chaos

        NASA Astrophysics Data System (ADS)

        Laprise, J. F.; Blondeau-Fournier, O.; Kröger, J.; Kröger, H.; St.-Louis, P. Y.; Dubé, L. J.; Endress, E.; Burra, A.; Zomorrodi, R.; Melkonyan, G.; Moriarty, K. J. M.

        2008-06-01

        We suggest that random matrix theory applied to a matrix of lengths of classical trajectories can be used in classical billiards to distinguish chaotic from non-chaotic behavior. We consider in 2D the integrable circular and rectangular billiard, the chaotic cardioid, Sinai and stadium billiard as well as mixed billiards from the Limaçon/Robnik family. From the spectrum of the length matrix we compute the level spacing distribution, the spectral auto-correlation and spectral rigidity. We observe non-generic (Dirac comb) behavior in the integrable case and Wignerian behavior in the chaotic case. For the Robnik billiard close to the circle the distribution approaches a Poissonian distribution. The length matrix elements of chaotic billiards display approximate GOE behavior. Our findings provide evidence for universality of level fluctuations-known from quantum chaos-to hold also in classical physics.

      16. First-order partial differential equations in classical dynamics

        NASA Astrophysics Data System (ADS)

        Smith, B. R.

        2009-12-01

        Carathèodory's classic work on the calculus of variations explores in depth the connection between ordinary differential equations and first-order partial differential equations. The n second-order ordinary differential equations of a classical dynamical system reduce to a single first-order differential equation in 2n independent variables. The general solution of first-order partial differential equations touches on many concepts central to graduate-level courses in analytical dynamics including the Hamiltonian, Lagrange and Poisson brackets, and the Hamilton-Jacobi equation. For all but the simplest dynamical systems the solution requires one or more of these techniques. Three elementary dynamical problems (uniform acceleration, harmonic motion, and cyclotron motion) can be solved directly from the appropriate first-order partial differential equation without the use of advanced methods. The process offers an unusual perspective on classical dynamics, which is readily accessible to intermediate students who are not yet fully conversant with advanced approaches.

      17. 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.

      18. 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. PMID:27367395

      19. 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.

      20. Integral approximations to classical diffusion and smoothed particle hydrodynamics

        DOE PAGESBeta

        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

      1. Simulation of non-classical diffusion in polymers

        NASA Astrophysics Data System (ADS)

        Wilmers, Jana; Bargmann, Swantje

        2014-05-01

        The present contribution is concerned with the computational modelling of non-classical diffusion in amorphous polymers. Special attention is paid to the limiting case of Case II diffusion. Application of the dual-phase-lag concept to Fick's first law leads to a description of Case II behaviour. The change in material properties during the glass transition is explicitly accounted for by a concentration dependent formulation of the material parameters. The proposed model is well suited for modelling the sharp diffusion front and linear uptake kinetics associated with Case II diffusion. Application of a concentration dependent diffusion coefficient reduces the concentration gradient behind the front to a minimum. For the solution procedure, a finite element scheme in space and a finite difference method in time are applied. Three-dimensional numerical results are presented for classical Fickian and non-classical Case II diffusion. This paper adds to the basic understanding of the computational modelling of the Case II diffusion phenomenon.

      2. Quantum-classical interactions through the path integral

        NASA Astrophysics Data System (ADS)

        Metaxas, Dimitrios

        2007-03-01

        I consider the case of two interacting scalar fields, ϕ and ψ, and use the path integral formalism in order to treat the first classically and the second quantum-mechanically. I derive the Feynman rules and the resulting equation of motion for the classical field which should be an improvement of the usual semiclassical procedure. As an application I use this method in order to enforce Gauss’s law as a classical equation in a non-Abelian gauge theory. I argue that the theory is renormalizable and equivalent to the usual Yang-Mills theory as far as the gauge field terms are concerned. There are additional terms in the effective action that depend on the Lagrange multiplier field λ that is used to enforce the constraint. These terms and their relation to the confining properties of the theory are discussed.

      3. Classical equation of motion and anomalous dimensions at leading order

        NASA Astrophysics Data System (ADS)

        Nii, Keita

        2016-07-01

        Motivated by a recent paper by Rychkov-Tan [1], we calculate the anomalous dimensions of the composite operators at the leading order in various models including a ϕ 3-theory in (6 - ɛ) dimensions. The method presented here relies only on the classical equation of motion and the conformal symmetry. In case that only the leading expressions of the critical exponents are of interest, it is sufficient to reduce the multiplet recombination discussed in [1] to the classical equation of motion. We claim that in many cases the use of the classical equations of motion and the CFT constraint on two- and three-point functions completely determine the leading behavior of the anomalous dimensions at the Wilson-Fisher fixed point without any input of the Feynman diagrammatic calculation. The method developed here is closely related to the one presented in [1] but based on a more perturbative point of view.

      4. Breakdown of the classical description of a local system.

        PubMed

        Kot, Eran; Grønbech-Jensen, Niels; Nielsen, Bo M; Neergaard-Nielsen, Jonas S; Polzik, Eugene S; Sørensen, Anders S

        2012-06-01

        We provide a straightforward demonstration of a fundamental difference between classical and quantum mechanics for a single local system: namely, the absence of a joint probability distribution of the position x and momentum p. Elaborating on a recently reported criterion by Bednorz and Belzig [Phys. Rev. A 83, 052113 (2011)] we derive a simple criterion that must be fulfilled for any joint probability distribution in classical physics. We demonstrate the violation of this criterion using the homodyne measurement of a single photon state, thus proving a straightforward signature of the breakdown of a classical description of the underlying state. Most importantly, the criterion used does not rely on quantum mechanics and can thus be used to demonstrate nonclassicality of systems not immediately apparent to exhibit quantum behavior. The criterion is directly applicable to any system described by the continuous canonical variables x and p, such as a mechanical or an electrical oscillator and a collective spin of a large ensemble. PMID:23003954

      5. Complementarity of quantum discord and classically accessible information

        DOE PAGESBeta

        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

      6. 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.

      7. Classical-quantum mixing in the random 2-satisfiability problem

        NASA Astrophysics Data System (ADS)

        Potirniche, Ionut-Dragos; Laumann, C. R.; Sondhi, S. L.

        2015-10-01

        Classical satisfiability (SAT) and quantum satisfiability (QSAT) are complete problems for the complexity classes NP and QMA, respectively, and they are believed to be intractable for both classical and quantum computers. Statistical ensembles of instances of these problems have been studied previously in an attempt to elucidate their typical, as opposed to worst-case, behavior. In this paper, we introduce a statistical ensemble that interpolates between classical and quantum. For the simplest 2-SAT-2-QSAT ensemble, we find the exact boundary that separates SAT and UNSAT instances. We do so by establishing coincident lower and upper bounds, in the limit of large instances, on the extent of the UNSAT and SAT regions, respectively.

      8. [The establishment, contributions, and final results of classical medical theories].

        PubMed

        Wang, Tai

        2013-01-01

        In countries with ancient civilization of both Eastern world and Western world, after the accumulation of clinical experiences of "empirical medicine" to a sufficient amount; in accordance of their primitive philosophical thoughts, classical medical theories were established to play an important role in guiding the clinical practice of "empirical medicine". Because of the similarity of philosophical thoughts all over the ancient world, their medical theories were also very similar to each other. After the scientific evaluation and improvement, Greek classical medical theories were inherited, refined or abandoned, and then eventually finished their historical mission. Chinese classical medical theories also need the similar scientific identification and improvement for flowing into the authorized main stream of modern medical theory systems to continuously apply their guiding roles in clinical practice. Scholars would better consider the developmental principles of cultures and sciences with a historical viewpoint and an open mind to avoid making mistakes from haughty and prejudice. PMID:23596779

      9. Novel Evasion Mechanisms of the Classical Complement Pathway.

        PubMed

        Garcia, Brandon L; Zwarthoff, Seline A; Rooijakkers, Suzan H M; Geisbrecht, Brian V

        2016-09-15

        Complement is a network of soluble and cell surface-associated proteins that gives rise to a self-amplifying, yet tightly regulated system with fundamental roles in immune surveillance and clearance. Complement becomes activated on the surface of nonself cells by one of three initiating mechanisms known as the classical, lectin, and alternative pathways. Evasion of complement function is a hallmark of invasive pathogens and hematophagous organisms. Although many complement-inhibition strategies hinge on hijacking activities of endogenous complement regulatory proteins, an increasing number of uniquely evolved evasion molecules have been discovered over the past decade. In this review, we focus on several recent investigations that revealed mechanistically distinct inhibitors of the classical pathway. Because the classical pathway is an important and specific mediator of various autoimmune and inflammatory disorders, in-depth knowledge of novel evasion mechanisms could direct future development of therapeutic anti-inflammatory molecules. PMID:27591336

      10. 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.

      11. A generalization of Fermat's principle for classical and quantum systems

        NASA Astrophysics Data System (ADS)

        Elsayed, Tarek A.

        2014-09-01

        The analogy between dynamics and optics had a great influence on the development of the foundations of classical and quantum mechanics. We take this analogy one step further and investigate the validity of Fermat's principle in many-dimensional spaces describing dynamical systems (i.e., the quantum Hilbert space and the classical phase and configuration space). We propose that if the notion of a metric distance is well defined in that space and the velocity of the representative point of the system is an invariant of motion, then a generalized version of Fermat's principle will hold. We substantiate this conjecture for time-independent quantum systems and for a classical system consisting of coupled harmonic oscillators. An exception to this principle is the configuration space of a charged particle in a constant magnetic field; in this case the principle is valid in a frame rotating by half the Larmor frequency, not the stationary lab frame.

      12. Classical Hodgkin's disease. Clinical impact of the immunophenotype.

        PubMed Central

        von Wasielewski, R.; Mengel, M.; Fischer, R.; Hansmann, M. L.; Hübner, K.; Franklin, J.; Tesch, H.; Paulus, U.; Werner, M.; Diehl, V.; Georgii, A.

        1997-01-01

        Antibodies against CD15, -30, and -20 are often used to support morphological diagnosis of Hodgkin's Disease (HD). The classical HD, i.e., the non-lymphocyte-predominance types, are CD15+, CD30+, and CD20- in general. However, the results for CD15 are less clear-cut in many studies, showing up to 40% of classical HD that lack positivity for this maker. Little is currently known about the relevance of antigen expression in relation to clinical outcome in HD. Therefore, the three markers were analyzed in 1751 cases from the German Hodgkin Study Group, using micro-wave epitope retrieval to optimize staining sensitivity. Eighty-three percent of the cases showed a classical immunophenotype (CD15+, CD30+, CD20-), twelve percent lacked CD15 positivity (CD15-, CD30+, CD20-), and five percent showed other combinations. For 1286 cases, clinical follow-up was available, which revealed significant differences for freedom from treatment failure (P = 0.0022) and overall survival (P = 0.0001) between cases with classical immunophenotype and CD15 negativity (CD30+, CD20-). Multivariate Cox regression using the three markers, age, sex, histology, stage, B-symptoms (fever, sweats, weight loss > 10% of body weight), hemoglobin, and erythrocyte sedimentation rate as factors showed that lack of CD15 expression in classical HD is an independent negative prognostic factor for relapses (P = 0.022) and survival (P = 0.0035). In conclusion, immunohistochemistry is able to identify classical HD cases with unfavorable clinical outcome. Images Figure 5 Figure 6 PMID:9327746

      13. 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).

      14. Relativistic classical integrable tops and quantum R-matrices

        NASA Astrophysics Data System (ADS)

        Levin, A.; Olshanetsky, M.; Zotov, A.

        2014-07-01

        We describe classical top-like integrable systems arising from the quantum exchange relations and corresponding Sklyanin algebras. The Lax operator is expressed in terms of the quantum non-dynamical R-matrix even at the classical level, where the Planck constant plays the role of the relativistic deformation parameter in the sense of Ruijsenaars and Schneider (RS). The integrable systems (relativistic tops) are described as multidimensional Euler tops, and the inertia tensors are written in terms of the quantum and classical R-matrices. A particular case of gl N system is gauge equivalent to the N-particle RS model while a generic top is related to the spin generalization of the RS model. The simple relation between quantum R-matrices and classical Lax operators is exploited in two ways. In the elliptic case we use the Belavin's quantum R-matrix to describe the relativistic classical tops. Also by the passage to the noncommutative torus we study the large N limit corresponding to the relativistic version of the nonlocal 2d elliptic hydrodynamics. Conversely, in the rational case we obtain a new gl N quantum rational non-dynamical R-matrix via the relativistic top, which we get in a different way — using the factorized form of the RS Lax operator and the classical Symplectic Hecke (gauge) transformation. In particular case of gl2 the quantum rational R-matrix is 11-vertex. It was previously found by Cherednik. At last, we describe the integrable spin chains and Gaudin models related to the obtained R-matrix.

      15. Revival of Classical Vortex Generators Now for Transition Delay

        NASA Astrophysics Data System (ADS)

        Shahinfar, Shahab; Sattarzadeh, Sohrab S.; Fransson, Jens H. M.; Talamelli, Alessandro

        2012-08-01

        Classical vortex generators, known for their efficiency in delaying or even inhibiting boundary layer separation, are here shown to be coveted devices for transition to turbulence delay. The present devices are miniature with respect to classical vortex generators but are tremendously powerful in modulating the laminar boundary layer in the direction orthogonal to the base flow and parallel to the surface. The modulation generates an additional term in the perturbation energy equation, which counteracts the wall-normal production term and, hence, stabilizes the flow. Our experimental results show that these devices are really effective in delaying transition, but we also reveal their Achilles’ heel.

      16. Quantum-classical correspondence in steady states of nonadiabatic systems

        SciTech Connect

        Fujii, Mikiya; Yamashita, Koichi

        2015-12-31

        We first present nonadiabatic path integral which is exact formulation of quantum dynamics in nonadiabatic systems. Then, by applying the stationary phase approximations to the nonadiabatic path integral, a semiclassical quantization condition, i.e., quantum-classical correspondence, for steady states of nonadiabatic systems is presented as a nonadiabatic trace formula. The present quantum-classical correspondence indicates that a set of primitive hopping periodic orbits, which are invariant under time evolution in the phase space of the slow degree of freedom, should be quantized. The semiclassical quantization is then applied to a simple nonadiabatic model and accurately reproduces exact quantum energy levels.

      17. 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.

      18. 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. PMID:26965624

      19. Perturbations around the zeros of classical orthogonal polynomials

        NASA Astrophysics Data System (ADS)

        Sasaki, Ryu

        2015-04-01

        Starting from degree N solutions of a time dependent Schrödinger-like equation for classical orthogonal polynomials, a linear matrix equation describing perturbations around the N zeros of the polynomial is derived. The matrix has remarkable Diophantine properties. Its eigenvalues are independent of the zeros. The corresponding eigenvectors provide the representations of the lower degree ( 0 , 1 , … , N - 1 ) polynomials in terms of the zeros of the degree N polynomial. The results are valid universally for all the classical orthogonal polynomials, including the Askey scheme of hypergeometric orthogonal polynomials and its q-analogues.

      20. The quantum-to-classical transition: contraction of associative products

        NASA Astrophysics Data System (ADS)

        Ibort, A.; Man'ko, V. I.; Marmo, G.; Simoni, A.; Stornaiolo, C.; Ventriglia, F.

        2016-04-01

        The quantum-to-classical transition is considered from the point of view of contractions of associative algebras. Various methods and ideas to deal with contractions of associative algebras are discussed that account for a large family of examples. As an instance of them, the commutative algebra of functions in phase space, corresponding to classical physical observables, is obtained as a contraction of the Moyal star-product which characterizes the quantum case. Contractions of associative algebras associated to Lie algebras are discussed, in particular the Weyl-Heisenberg and SU(2) groups are considered.

      1. 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.

      2. Absolute relativity in classical electromagnetism: the quantisation of light

        NASA Astrophysics Data System (ADS)

        Williamson, J. G.; Leary, S. J.

        2015-09-01

        A rigorous introduction of the underlying nature of space and time, through a sharpening of the principle of relativity, forces qualitatively new kinds of solutions in the classical theory of electromagnetism. A class of relativistic wave-functions are derived which are solutions to the first-order, free-space Maxwell equation, These describe all photons from radio to gamma waves and are governed by a single parameter: the exchange frequency. Though the theory remains that of classical, continuous electromagnetism, allowed travelling-wave solutions are quantised in that they come in "lumps" and their characteristic energy is proportional to frequency.

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

        NASA Astrophysics Data System (ADS)

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

        2016-08-01

        Optical spectroscopy study of the recent 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.

      4. Sharing of classical and quantum correlations via XY interaction

        SciTech Connect

        Wang, Jieci; Silva, Jaime; Lanceros-Mendez, Senentxu

        2014-09-15

        The sharing of classical and quantum correlations via XY interaction is investigated. The model includes two identical networks consisting of n nodes, the ith node of one network sharing a correlated state with the jth node of the other network, while all other nodes are initially unconnected. It is shown that classical correlation, quantum discord as well as entanglement can be shared between any two nodes of the network via XY interaction and that quantum information can be transferred effectively between them. It is found that there is no simple dominating relation between the quantum correlation and entanglement in inertial system.

      5. Entanglement, the quantum formalism and the classical world

        SciTech Connect

        Matzkin, A.

        2011-09-23

        75 years after the term 'entanglement' was coined to a peculiar feature inherent to quantum systems, the connection between quantum and classical mechanics remains an open problem. Drawing on recent results obtained in semiclassical systems, we discuss here the fate of entanglement in a closed system as Planck's constant becomes vanishingly small. In that case the generation of entanglement in a quantum system is perfectly reproduced by properly defined correlations of the corresponding classical system. We speculate on what these results could imply regarding the status of entanglement and of the ensuing quantum correlations.

      6. Twisting all the way: From classical mechanics to quantum fields

        SciTech Connect

        Aschieri, Paolo

        2008-01-15

        We discuss the effects that a noncommutative geometry induced by a Drinfeld twist has on physical theories. We systematically deform all products and symmetries of the theory. We discuss noncommutative classical mechanics, in particular its deformed Poisson bracket and hence time evolution and symmetries. The twisting is then extended to classical fields, and then to the main interest of this work: quantum fields. This leads to a geometric formulation of quantization on noncommutative space-time, i.e., we establish a noncommutative correspondence principle from *-Poisson brackets to * commutators. In particular commutation relations among creation and annihilation operators are deduced.

      7. Usefulness of classical communication for local cloning of entangled states

        SciTech Connect

        Demkowicz-Dobrzanski, Rafal; Sen, Aditi; Sen, Ujjwal; Bruss, Dagmar

        2006-03-15

        We solve the problem of the optimal cloning of pure entangled two-qubit states with a fixed degree of entanglement using local operations and classical communication. We show that, amazingly, classical communication between the parties can improve the fidelity of local cloning if and only if the initial entanglement is higher than a certain critical value. It is completely useless for weakly entangled states. We also show that bound entangled states with positive partial transpose are not useful as a resource to improve the best local cloning fidelity.

      8. Bohmian mechanics, collapse models and the emergence of classicality

        NASA Astrophysics Data System (ADS)

        Toroš, Marko; Donadi, Sandro; Bassi, Angelo

        2016-09-01

        We discuss the emergence of classical trajectories in Bohmian mechanics, when a macroscopic object interacts with an external environment. We show that in such a case the conditional wave function of the system follows a dynamics which, under reasonable assumptions, corresponds to that of the Ghirardi–Rimini–Weber (GRW) collapse model. As a consequence, Bohmian trajectories evolve classically. Our analysis also shows how the GRW (istantaneous) collapse process can be derived by an underlying continuous interaction of a quantum system with an external agent, thus throwing a light on how collapses can emerge from a deeper level theory.

      9. Dynamic stabilization of classical Rayleigh-Taylor instability

        SciTech Connect

        Piriz, A. R.; Piriz, S. A.; Tahir, N. A.

        2011-09-15

        Dynamic stabilization of classical Rayleigh-Taylor instability is studied by modeling the interface vibration with the simplest possible wave form, namely, a sequence of Dirac deltas. As expected, stabilization results to be impossible. However, in contradiction to previously reported results obtained with a sinusoidal driving, it is found that in general the perturbation amplitude is larger than in the classical case. Therefore, no beneficial effect can be obtained from the vertical vibration of a Rayleigh-Taylor unstable interface between two ideal fluids.

      10. Violations of a new inequality for classical fields

        NASA Technical Reports Server (NTRS)

        Franson, J. D.

        1992-01-01

        Two entangled photons incident upon two distant interferometers can give a coincidence counting rate that depends nonlocally on the sum of the phases of the two interferometers. It has recently been shown that experiments of this kind may violate a simple inequality that must be satisfied by any classical or semi-classical field theory. The inequality provides a graphic illustration of the lack of objective realism of the electric field. The results of a recent experiment which violates this inequality and in which the optical path length between the two interferometers was greater than 100 m are briefly described.

      11. 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.

      12. Quasi-classical models of transition state absorption or emission

        NASA Astrophysics Data System (ADS)

        Lee, Soo-Y.; Pollard, W. Thomas; Mathies, Richard A.

        1989-11-01

        By making a short-time approximation to the correlation function in the quantum result for transition state absorption (or emission) we obtain the Lorentzian and reflection results as integrals of simple configuration space functions. These and the time-integrated quantum results are used to derive and unify the following descriptions of transition-state absorption: (a) the classical model of Bersohn and Zewail, (b) the time-dependent wave mechanical description by Agrawal, Mohan and Sathyamurthy, (c) the classical trajectory approach by Polanyi and coworkers and (d) the time-independent quantum-mechanical description by Engel, Bacic, Schinke and Shapiro.

      13. Adolescent Literature as a Complement to the Classics. Volume 4.

        ERIC Educational Resources Information Center

        Kaywell, Joan F., Ed.

        This book is based on two assumptions: the classics comprise the canon of literature that is mostly taught in schools; and most teachers are familiar with adolescent literature but are unsure how to incorporate its use in classrooms. This book provides the necessary information so that teachers may confidently use young adult novels in conjunction…

      14. Bidirectional Classical Stochastic Processes with Measurements and Feedback

        NASA Technical Reports Server (NTRS)

        Hahne, G. E.

        2005-01-01

        A measurement on a quantum system is said to cause the "collapse" of the quantum state vector or density matrix. An analogous collapse occurs with measurements on a classical stochastic process. This paper addresses the question of describing the response of a classical stochastic process when there is feedback from the output of a measurement to the input, and is intended to give a model for quantum-mechanical processes that occur along a space-like reaction coordinate. The classical system can be thought of in physical terms as two counterflowing probability streams, which stochastically exchange probability currents in a way that the net probability current, and hence the overall probability, suitably interpreted, is conserved. The proposed formalism extends the . mathematics of those stochastic processes describable with linear, single-step, unidirectional transition probabilities, known as Markov chains and stochastic matrices. It is shown that a certain rearrangement and combination of the input and output of two stochastic matrices of the same order yields another matrix of the same type. Each measurement causes the partial collapse of the probability current distribution in the midst of such a process, giving rise to calculable, but non-Markov, values for the ensuing modification of the system's output probability distribution. The paper concludes with an analysis of a classical probabilistic version of the so-called grandfather paradox.

      15. Classical-Conditioning Demonstrations for Elementary and Advanced Courses.

        ERIC Educational Resources Information Center

        Abramson, Charles I.; And Others

        1996-01-01

        Describes two new exercises in classical conditioning that use earthworms and houseflies. The animals are available year-round and pose no risk to the students or instructor. The conditioned stimuli are odorants. These elicit a conditioned response of contraction in worms or proboscis extension in flies. (MJP)

      16. Constrained variational calculus for higher order classical field theories

        NASA Astrophysics Data System (ADS)

        Campos, Cédric M.; de León, Manuel; Martín de Diego, David

        2010-11-01

        We develop an intrinsic geometrical setting for higher order constrained field theories. As a main tool we use an appropriate generalization of the classical Skinner-Rusk formalism. Some examples of applications are studied, in particular to the geometrical description of optimal control theory for partial differential equations.

      17. Teaching Classical Sociological Theory in Singapore: The Context of Eurocentrism.

        ERIC Educational Resources Information Center

        Alatas, Syed Farid; Sinha, Vineeta

        2001-01-01

        Argues that there is a need to rethink the teaching of classical sociological theories. Focuses on the reasons the authors rethought their course with a special emphasis on their critique of Eurocentrism. Discusses the course and the responses of students to the new version of the course. Includes references. (CMK)

      18. American Children's Classics: Which Will Fade, Which Endure?

        ERIC Educational Resources Information Center

        Fenwick, Sara Innis

        1972-01-01

        The author recommends Tom Sawyer,'' Huckleberry Finn,'' Hans Brinker,'' Little Women,'' The Story of a Bad Boy,'' and The Peterkin Papers,'' as the major classics with current appeal. Also included are a few more recent titles recommended for children's reading. (SJ)

      19. Marshaling Resources: A Classic Grounded Theory Study of Online Learners

        ERIC Educational Resources Information Center

        Yalof, Barbara

        2012-01-01

        Students who enroll in online courses comprise one quarter of an increasingly diverse student body in higher education today. Yet, it is not uncommon for an online program to lose over 50% of its enrolled students prior to graduation. This study used a classic grounded theory qualitative methodology to investigate the persistent problem of…

      20. Electrochemical phase formation: classical and atomistic theoretical models.

        PubMed

        Milchev, Alexander

        2016-08-01

        The process of electrochemical phase formation at constant thermodynamic supersaturation is considered in terms of classical and atomistic nucleation theories. General theoretical expressions are derived for important thermodynamic and kinetic quantities commenting also upon the correlation between the existing theoretical models and experimental results. Progressive and instantaneous nucleation and growth of multiple clusters of the new phase are briefly considered, too. PMID:27108683

      1. Brain Mechanisms of Extinction of the Classically Conditioned Eyeblink Response

        ERIC Educational Resources Information Center

        Thompson, Richard F.; Robleto, Karla; Poulos, Andrew M.

        2004-01-01

        It is well established that the cerebellum and its associated circuitry are essential for classical conditioning of the eyeblink response and other discrete motor responses (e.g., limb flexion, head turn, etc.) learned with an aversive unconditioned stimulus (US). However, brain mechanisms underlying extinction of these responses are still…

      2. Classic Articles in Special Education: An Exploratory Investigation

        ERIC Educational Resources Information Center

        McLeskey, James; Landers, Eric

        2006-01-01

        This exploratory investigation sought to identify classic articles from the general special education literature that were published between 1960 and 1989. Initially, widely cited articles that were published during this time in "Exceptional Children, Remedial and Special Education," and "The Journal of Special Education" were identified. Faculty…

      3. Classics Reconsidered: Tolstoy in the Middle School Classroom.

        ERIC Educational Resources Information Center

        Kazemek, Francis E.

        1998-01-01

        Argues that classic authors can and should still be kept at the center of the literature curricula in the middle school. Uses Leo Tolstoy as an example, describing briefly some of Tolstoy's works that are especially appropriate for early middle school readers, later middle schoolers of average reading ability, and the most able middle school…

      4. On the Galilean Non-Invariance of Classical Electromagnetism

        ERIC Educational Resources Information Center

        Preti, Giovanni; de Felice, Fernando; Masiero, Luca

        2009-01-01

        When asked to explain the Galilean non-invariance of classical electromagnetism on the basis of pre-relativistic considerations alone, students--and sometimes their teachers too--may face an impasse. Indeed, they often argue that a pre-relativistic physicist could most obviously have provided the explanation "at a glance", on the basis of the…

      5. The Public Debt as Seen by the Classical Economists.

        ERIC Educational Resources Information Center

        Labbens, Jean

        1987-01-01

        Reviews classical economists' views on the issue of public debt. Notes that from antiquity to modern times, it has always been rare for a state not to be in debt. Includes an examination of a state's repudiation of its debt and the impact such an action might have on its international relations. (JDH)

      6. Reimer through Confucian Lenses: Resonances with Classical Chinese Aesthetics

        ERIC Educational Resources Information Center

        Tan, Leonard

        2015-01-01

        In this paper, I compare all three editions of Bennett Reimer's "A Philosophy of Music Education" with early Chinese philosophy, in particular, classical Chinese aesthetics. I structure my analysis around a quartet of interrelated themes: aesthetic education, education of feeling, aesthetic experience, and ethics and aesthetics. This…

      7. Autonomous quantum to classical transitions and the generalized imaging theorem

        NASA Astrophysics Data System (ADS)

        Briggs, John S.; Feagin, James M.

        2016-03-01

        The mechanism of the transition of a dynamical system from quantum to classical mechanics is of continuing interest. Practically it is of importance for the interpretation of multi-particle coincidence measurements performed at macroscopic distances from a microscopic reaction zone. Here we prove the generalized imaging theorem which shows that the spatial wave function of any multi-particle quantum system, propagating over distances and times large on an atomic scale but still microscopic, and subject to deterministic external fields and particle interactions, becomes proportional to the initial momentum wave function where the position and momentum coordinates define a classical trajectory. Currently, the quantum to classical transition is considered to occur via decoherence caused by stochastic interaction with an environment. The imaging theorem arises from unitary Schrödinger propagation and so is valid without any environmental interaction. It implies that a simultaneous measurement of both position and momentum will define a unique classical trajectory, whereas a less complete measurement of say position alone can lead to quantum interference effects.

      8. Mistaken gender identity in non-classical congenital adrenal hyperplasia

        PubMed Central

        Kukreti, Prerna; Kandpal, Manish; Jiloha, R. C.

        2014-01-01

        Gender identity is the sense of belonging that one feels for a particular sex psychologically and socially, independent of one's biological sex. There is much less systematic data on gender identity in females with congenital adrenal hyperplasia (CAH). We report a case of non-classical CAH presenting as a case of gender identity disorder. PMID:24891708

      9. Some Early Optics: Classical and Medieval. Experiment No. 6.

        ERIC Educational Resources Information Center

        Devons, Samuel

        Information related to the history of optics with emphasis on the classical and medieval periods is presented. Notes are included on experiments dealing with refraction at a plane interface between two media; refraction by transparent spheres; light, color, and reflection by transparent spheres. (Author/SA)

      10. Using Classic and Contemporary Visual Images in Clinical Teaching.

        ERIC Educational Resources Information Center

        Edwards, Janine C.

        1990-01-01

        The patient's body is an image that medical students and residents use to process information. The classic use of images using the patient is qualitative and personal. The contemporary use of images is quantitative and impersonal. The contemporary use of imaging includes radiographic, nuclear, scintigraphic, and nuclear magnetic resonance…

      11. An Address to the Classical Association of Western New York.

        ERIC Educational Resources Information Center

        Wooby, Philip F.

        1966-01-01

        Highlighting this article which argues in defense of classical language, literature, and cultural studies is a brief description of the history and development of the Latin language, its emergence into modern tongues, its direct Etruscan derivation, and its fixed and formal nature. Other topics treated briefly include a distinction made between…

      12. Classic Book Units for G/C/T Youngsters.

        ERIC Educational Resources Information Center

        Karges-Bone, Linda

        1991-01-01

        Use of classic book units with gifted elementary students is described as an interdisciplinary approach to stimulating student interest. Sample activities are offered from a unit on Mark Twain's "Huckleberry Finn," with linguistic, artistic-creative, scientific, mathematical, and socio-leadership activities, classified as application, synthesis,…

      13. Structure of classical trajectories in multidimensional bound molecular systems

        SciTech Connect

        Ashton, C.J.; Muckerman, J.T.

        1983-07-21

        A computational method is described which enables visualization of the coordinate space envelopes of classical trajectories in multidimensional bound molecular systems. The method is exemplified by application to a realistic three-dimensional model of the vibrating water molecule, and its utility in the application of semiclassical quantization techniques is emphasized. 8 figures.

      14. "Citation Classics" Analysis: An Approach to Characterizing Interdisciplinary Research.

        ERIC Educational Resources Information Center

        Chubin, Daryl E.; And Others

        1984-01-01

        This article adopts "citation approach" to distinguish interdisciplinary or multidisciplinary research (IDR) from monodisciplinary research and begins to descrie how IDR differs from other research. Ten-year citation histories were constructed for sample of 1981 "citation classics" (over-cited articles) and examined for suspected IDR content…

      15. With Rigor for All: Teaching the Classics to Contemporary Students.

        ERIC Educational Resources Information Center

        Jago, Carol

        This book challenges the current penchant in United States education for "dumbing down" and anthologizing literature for secondary learners. The book provides a rationale for teaching the classics to all high school students. It offers a wealth of ways for English teachers to do what they yearn to do in their own classrooms: teach "the good…

      16. Experimental multiplexing of quantum key distribution with classical optical communication

        NASA Astrophysics Data System (ADS)

        Wang, Liu-Jun; Chen, Luo-Kan; Ju, Lei; Xu, Mu-Lan; Zhao, Yong; Chen, Kai; Chen, Zeng-Bing; Chen, Teng-Yun; Pan, Jian-Wei

        2015-02-01

        We demonstrate the realization of quantum key distribution (QKD) when combined with classical optical communication, and synchronous signals within a single optical fiber. In the experiment, the classical communication sources use Fabry-Pérot (FP) lasers, which are implemented extensively in optical access networks. To perform QKD, multistage band-stop filtering techniques are developed, and a wavelength-division multiplexing scheme is designed for the multi-longitudinal-mode FP lasers. We have managed to maintain sufficient isolation among the quantum channel, the synchronous channel and the classical channels to guarantee good QKD performance. Finally, the quantum bit error rate remains below a level of 2% across the entire practical application range. The proposed multiplexing scheme can ensure low classical light loss, and enables QKD over fiber lengths of up to 45 km simultaneously when the fibers are populated with bidirectional FP laser communications. Our demonstration paves the way for application of QKD to current optical access networks, where FP lasers are widely used by the end users.

      17. The Adiabatic Invariance of the Action Variable in Classical Dynamics

        ERIC Educational Resources Information Center

        Wells, Clive G.; Siklos, Stephen T. C.

        2007-01-01

        We consider one-dimensional classical time-dependent Hamiltonian systems with quasi-periodic orbits. It is well known that such systems possess an adiabatic invariant which coincides with the action variable of the Hamiltonian formalism. We present a new proof of the adiabatic invariance of this quantity and illustrate our arguments by means of…

      18. From Classical to Quantum Saturation in the Nuclear Wavefunction

        NASA Astrophysics Data System (ADS)

        Triantafyllopoulos, D. N.

        2005-01-01

        We study the gluon content of a large nucleus (i) in the semi-classical McLerran-Venugopalan model and (ii) in the high energy limit as given by the quantum evolution of the Color Glass Condensate. We give a qualitative description of the Cronin effect and high-p⊥ suppression in proton-nucleus collisions.

      19. From classical to quantum saturationin the nuclear gluon distribution

        NASA Astrophysics Data System (ADS)

        Triantafyllopoulos, D. N.

        2005-08-01

        We study the gluon content of a large nucleus (i) in the semi-classical McLerran-Venugopalan model and (ii) in the high-energy limit as given by the quantum evolution of the color glass condensate. We give a simple and qualitative description of the Cronin effect and high- pT suppression in proton-nucleus collisions.

      20. When Did Classic Composers Make Their Best Work?

        ERIC Educational Resources Information Center

        Franses, Philip Hans

        2016-01-01

        This Research Note shows that classic composers created their best works when they were at a similar age when creators in other domains did their best work, namely when they were at an age that represented around 60% of their life span. This finding is very similar to earlier results for painters and authors.