Iwo Bialynicki-Birula
2005-08-26
Photon wave function is a controversial concept. Controversies stem from the fact that photon wave functions can not have all the properties of the Schroedinger wave functions of nonrelativistic wave mechanics. Insistence on those properties that, owing to peculiarities of photon dynamics, cannot be rendered, led some physicists to the extreme opinion that the photon wave function does not exist. I reject such a fundamentalist point of view in favor of a more pragmatic approach. In my view, the photon wave function exists as long as it can be precisely defined and made useful.
Adaptive multiconfigurational wave functions
Evangelista, Francesco A.
2014-03-28
A method is suggested to build simple multiconfigurational wave functions specified uniquely by an energy cutoff ?. These are constructed from a model space containing determinants with energy relative to that of the most stable determinant no greater than ?. The resulting ?-CI wave function is adaptive, being able to represent both single-reference and multireference electronic states. We also consider a more compact wave function parameterization (?+SD-CI), which is based on a small ?-CI reference and adds a selection of all the singly and doubly excited determinants generated from it. We report two heuristic algorithms to build ?-CI wave functions. The first is based on an approximate prescreening of the full configuration interaction space, while the second performs a breadth-first search coupled with pruning. The ?-CI and ?+SD-CI approaches are used to compute the dissociation curve of N{sub 2} and the potential energy curves for the first three singlet states of C{sub 2}. Special attention is paid to the issue of energy discontinuities caused by changes in the size of the ?-CI wave function along the potential energy curve. This problem is shown to be solvable by smoothing the matrix elements of the Hamiltonian. Our last example, involving the Cu{sub 2}O{sub 2}{sup 2+} core, illustrates an alternative use of the ?-CI method: as a tool to both estimate the multireference character of a wave function and to create a compact model space to be used in subsequent high-level multireference coupled cluster computations.
Properties of resonance wave functions.
NASA Technical Reports Server (NTRS)
More, R. M.; Gerjuoy, E.
1973-01-01
Construction and study of resonance wave functions corresponding to poles of the Green's function for several illustrative models of theoretical interest. Resonance wave functions obtained from the Siegert and Kapur-Peierls definitions of the resonance energies are compared. The comparison especially clarifies the meaning of the normalization constant of the resonance wave functions. It is shown that the wave functions may be considered renormalized in a sense analogous to that of quantum field theory. However, this renormalization is entirely automatic, and the theory has neither ad hoc procedures nor infinite quantities.
Random wave functions and percolation
E. Bogomolny; C. Schmit
2007-08-31
Recently it was conjectured that nodal domains of random wave functions are adequately described by critical percolation theory. In this paper we strengthen this conjecture in two respects. First, we show that, though wave function correlations decay slowly, a careful use of Harris' criterion confirms that these correlations are unessential and nodal domains of random wave functions belong to the same universality class as non critical percolation. Second, we argue that level domains of random wave functions are described by the non-critical percolation model.
Wave function as geometric entity
B. I. Lev
2011-02-10
A new approach to the geometrization of the electron theory is proposed. The particle wave function is represented by a geometric entity, i.e., Clifford number, with the translation rules possessing the structure of Dirac equation for any manifold. A solution of this equation is obtained in terms of geometric treatment. Interference of electrons whose wave functions are represented by geometric entities is considered. New experiments concerning the geometric nature of electrons are proposed.
Meson wave function from holographic approaches
Alfredo Vega; Ivan Schmidt; Tanja Branz; Thomas Gutsche; Valery E. Lyubovitskij
2010-02-08
We discuss the light-front wave function for the valence quark state of mesons using the AdS/CFT correspondence. We consider two kinds of wave functions obtained in different holographic Soft-Wall approaches
Trigonimetric Trial Wave Function for the Hydrogen Atom Trial wave function: r ,( ) 3
Rioux, Frank
Trigonimetric Trial Wave Function for the Hydrogen Atom Trial wave function: r ,( ) 3 3 3 sech energy operatory: V 1 r -= a. Demonstrate the wave function is normalized. 0 r r ,( )2 4 r 2 d. Calculate the percent error. .5- E ( )- .5- 100 3.84= e. Compare optimized trial wave function
Wirosoetisno, Djoko
FastFEM: Breaking Wave Impact on Ships Wave breaking and wave impact on maritime structures on fast ships. Faster ships have become more important in recent years. These include pilot ships, supply ships to oil rigs, repair vessels for offshore wind farms, rescue vessels, and coast guard vessels
PRESSURE IMPULSES CAUSED BY WAVE IMPACT
Cox, Simon
PRESSURE IMPULSES CAUSED BY WAVE IMPACT A thesis submitted to the School of Mathematics's prior, written consent. #12; Abstract Coastal sea defences fail when the impact pressures due by solving a boundary value problem for the Pressure Impulse, the integral of pressure over the short time
Unstable particle's wave-function renormalization prescription
Yong Zhou
2005-12-17
We strictly define two set Wave-function Renormalization Constants (WRC) under the LSZ reduction formula for unstable particles at the first time. Then by introducing antiparticle's WRC and the CPT conservation law we obtain a new wave-function renormalization condition which can be used to totally determine the two set WRC. We calculate two physical processes to manifest the consistence of the present wave-function renormalization prescription with the gauge theory in standard model. We also prove that the conventional wave-function renormalization prescription which discards the imaginary part of unstable particle's WRC leads to physical amplitude gauge dependent.
Impact of non-hydrostatic effects and trapped lee waves on mountain wave drag
Wirosoetisno, Djoko
Impact of non-hydrostatic effects and trapped lee waves on mountain wave drag in directionally effects and trapped lee waves on mountain wave drag in directionally sheared flow. Quarterly Journal;AcceptedArticle Impact of non-hydrostatic effects and trapped lee waves on mountain wave drag
Stochastic Quantum Trajectories without a Wave Function
Jeroen C. Vink
2015-03-16
After summarizing three versions of trajectory-based quantum mechanics, it is argued that only the original formulation due to Bohm, which uses the Schr\\"odinger wave function to guide the particles, can be readily extended to particles with spin. To extend the two wave function-free formulations, it is argued that necessarily particle trajectories not only determine location, but also spin. Since spin values are discrete, it is natural to revert to a variation of Bohm's pilot wave formulation due originally to Bell. It is shown that within this formulation with stochastic quantum trajectories, a wave function free formulation can be obtained.
Wave function derivation of the JIMWLK equation
Alexey V. Popov
2008-12-16
Using the stationary lightcone perturbation theory, we propose the complete and careful derivation the JIMWLK equation. We show that the rigorous treatment requires the knowledge of a boosted wave function with second order accuracy. Previous wave function approaches are incomplete and implicitly used the time ordered perturbation theory, which requires a usage of an external target field.
On the Deutron Relativistic Wave Function
L. Abesalashvili; L. Akhobadze; V. Garsevanishvili; T. Jalagania; Yu. Tevzadze
2011-02-23
Light front form of the relativization of the deuteron wave function is considered. Parametars of the wave function are extracted comparing theoretical results with experimental data. Experimental data are obtained on the two-metre propane bubble chamber of JINR (Dubna) bombarded by the deutron beam with momentum of 4.2 GeV/c/nucleon
Meson wave function from holographic models
Alfredo Vega; Ivan Schmidt; Tanja Branz; Thomas Gutsche; Valery Lyubovitskij
2009-06-05
We consider the light-front wave function for the valence quark state of mesons using the AdS/CFT correspondence, as has been suggested by Brodsky and Teramond. Two kinds of wave functions, obtained in different holographic Soft-Wall models, are discussed.
A Wave-function for Stringy Universes
Costas Kounnas; Nicolaos Toumbas; Jan Troost
2007-07-27
We define a wave-function for string theory cosmological backgrounds. We give a prescription for computing its norm following an earlier analysis within general relativity. Under Euclidean continuation, the cosmologies we discuss in this paper are described in terms of compact parafermionic worldsheet systems. To define the wave-function we provide a T-fold description of the parafermionic conformal field theory, and of the corresponding string cosmology. In specific examples, we compute the norm of the wave-function and comment on its behavior as a function of moduli.
Solve spheroidal wave functions by SUSY method
Guihui Tian; Shuquan Zhong
2009-12-10
The perturbation method in supersymmetric quantum mechanics (SUSYQM) is used to study the spheroidal wave functions' eigenvalue problem. Expanding the super-potential in series of the parameter alpha, the first order term of ground eigen-value and the eigen-function are gotten. In the paper, the very excellent results are that all the first two terms approximation on eigenfunctions obtained are in closed form. They give useful information for the involved physical problems in application of spheroidal wave functions.
Stress Wave Source Characterization: Impact, Fracture, and Sliding Friction
NASA Astrophysics Data System (ADS)
McLaskey, Gregory Christofer
Rapidly varying forces, such as those associated with impact, rapid crack propagation, and fault rupture, are sources of stress waves which propagate through a solid body. This dissertation investigates how properties of a stress wave source can be identified or constrained using measurements recorded at an array of sensor sites located far from the source. This methodology is often called the method of acoustic emission and is useful for structural health monitoring and the noninvasive study of material behavior such as friction and fracture. In this dissertation, laboratory measurements of 1--300 mm wavelength stress waves are obtained by means of piezoelectric sensors which detect high frequency (10 kHz--3MHz) motions of a specimen's surface, picometers to nanometers in amplitude. Then, stress wave source characterization techniques are used to study ball impact, drying shrinkage cracking in concrete, and the micromechanics of stick-slip friction of Poly(methyl methacrylate) (PMMA) and rock/rock interfaces. In order to quantitatively relate recorded signals obtained with an array of sensors to a particular stress wave source, wave propagation effects and sensor distortions must be accounted for. This is achieved by modeling the physics of wave propagation and transduction as linear transfer functions. Wave propagation effects are precisely modeled by an elastodynamic Green's function, sensor distortion is characterized by an instrument response function, and the stress wave source is represented with a force moment tensor. These transfer function models are verified though calibration experiments which employ two different mechanical calibration sources: ball impact and glass capillary fracture. The suitability of the ball impact source model, based on Hertzian contact theory, is experimentally validated for small (˜1 mm) balls impacting massive plates composed of four different materials: aluminum, steel, glass, and PMMA. Using this transfer function approach and the two mechanical calibration sources, four types of piezoelectric sensors were calibrated: three commercially available sensors and the Glaser-type conical piezoelectric sensor, which was developed in the Glaser laboratory. The distorting effects of each sensor are modeled using autoregressive-moving average (ARMA) models, and because vital phase information is robustly incorporated into these models, they are useful for simulating or removing sensor-induced distortions, so that a displacement time history can be retrieved from recorded signals. The Glaser-type sensor was found to be very well modeled as a unidirectional displacement sensor which detects stress wave disturbances down to about 1 picometer in amplitude. Finally, the merits of a fully calibrated experimental system are demonstrated in a study of stress wave sources arising from sliding friction, and the relationship between those sources and earthquakes. A laboratory friction apparatus was built for this work which allows the micro-mechanisms of friction to be studied with stress wave analysis. Using an array of 14 Glaser-type sensors, and precise models of wave propagation effects and the sensor distortions, the physical origins of the stress wave sources are explored. Force-time functions and focal mechanisms are determined for discrete events found amid the "noise" of friction. These localized events are interpreted to be the rupture of micrometer-sized contacts, known as asperities. By comparing stress wave sources from stick-slip experiments on plastic/plastic and rock/rock interfaces, systematic differences were found. The rock interface produces very rapid (<1 microsecond) implosive forces indicative of brittle asperity failure and fault gouge formation, while rupture on the plastic interface releases only shear force and produces a source more similar to earthquakes commonly recorded in the field. The difference between the mechanisms is attributed to the vast differences in the hardness and melting temperatures of the two materials, which affect the distribution of asp
The Wave Function and Quantum Reality
Shan Gao
2011-08-04
We investigate the meaning of the wave function by analyzing the mass and charge density distribution of a quantum system. According to protective measurement, a charged quantum system has mass and charge density proportional to the modulus square of its wave function. It is shown that the mass and charge density is not real but effective, and it is formed by the ergodic motion of a localized particle with the total mass and charge of the system. Moreover, it is argued that the ergodic motion is not continuous but discontinuous and random. This result suggests a new interpretation of the wave function, according to which the wave function is a description of random discontinuous motion of particles, and the modulus square of the wave function gives the probability density of the particles being in certain locations. It is shown that the suggested interpretation of the wave function disfavors the de Broglie-Bohm theory and the many-worlds interpretation but favors the dynamical collapse theories, and the random discontinuous motion of particles may provide an appropriate random source to collapse the wave function.
Spatial wave functions of photon and electron
Khokhlov, D. L.
2010-12-01
The quantum mechanical model of the photon and electron is considered. The photon is conceived of as a particle moving with the speed of light which is accompanied by the wave function of the photon spreading out with an infinite speed. The wave function of the electron is introduced in terms of virtual photons tied to the electron. A description of electrostatic and magnetostatic interactions is given through the wave functions of electrons. The approach provides an explanation of the results of recent experiments measuring the speed of propagation of the bound magnetic field.
Sculpturing the Electron Wave Function
Shiloh, Roy; Lilach, Yigal; Arie, Ady
2014-01-01
Coherent electrons such as those in electron microscopes, exhibit wave phenomena and may be described by the paraxial wave equation. In analogy to light-waves, governed by the same equation, these electrons share many of the fundamental traits and dynamics of photons. Today, spatial manipulation of electron beams is achieved mainly using electrostatic and magnetic fields. Other demonstrations include simple phase-plates and holographic masks based on binary diffraction gratings. Altering the spatial profile of the beam may be proven useful in many fields incorporating phase microscopy, electron holography, and electron-matter interactions. These methods, however, are fundamentally limited due to energy distribution to undesired diffraction orders as well as by their binary construction. Here we present a new method in electron-optics for arbitrarily shaping of electron beams, by precisely controlling an engineered pattern of thicknesses on a thin-membrane, thereby molding the spatial phase of the electron wav...
Modeling of Wave Impact Using a Pendulum System
Nie, Chunyong
2011-08-08
For high speed vessels and offshore structures, wave impact, a main source of environmental loads, causes high local stresses and structural failure. However, the prediction of wave impact loads presents numerous challenges due to the complex nature...
Weak measurement and Bohmian conditional wave functions
Norsen, Travis; Struyve, Ward
2014-11-15
It was recently pointed out and demonstrated experimentally by Lundeen et al. that the wave function of a particle (more precisely, the wave function possessed by each member of an ensemble of identically-prepared particles) can be “directly measured” using weak measurement. Here it is shown that if this same technique is applied, with appropriate post-selection, to one particle from a perhaps entangled multi-particle system, the result is precisely the so-called “conditional wave function” of Bohmian mechanics. Thus, a plausibly operationalist method for defining the wave function of a quantum mechanical sub-system corresponds to the natural definition of a sub-system wave function which Bohmian mechanics uniquely makes possible. Similarly, a weak-measurement-based procedure for directly measuring a sub-system’s density matrix should yield, under appropriate circumstances, the Bohmian “conditional density matrix” as opposed to the standard reduced density matrix. Experimental arrangements to demonstrate this behavior–and also thereby reveal the non-local dependence of sub-system state functions on distant interventions–are suggested and discussed. - Highlights: • We study a “direct measurement” protocol for wave functions and density matrices. • Weakly measured states of entangled particles correspond to Bohmian conditional states. • Novel method of observing quantum non-locality is proposed.
Localized and Delocalized Wave Functions for Butadiene Frank Rioux
Rioux, Frank
Localized and Delocalized Wave Functions for Butadiene Frank Rioux The generation of localized wave functions present a problem for chemists who are accoustomed to localizing the -electrons the delocalized, canonical wave functions by invoking the quantum mechanical superposition principle
On single nucleon wave functions in nuclei
Talmi, Igal
2011-05-06
The strong and singular interaction between nucleons, makes the nuclear many body theory very complicated. Still, nuclei exhibit simple and regular features which are simply described by the shell model. Wave functions of individual nucleons may be considered just as model wave functions which bear little resemblance to the real ones. There is, however, experimental evidence for the reality of single nucleon wave functions. There is a simple method of constructing such wave functions for valence nucleons. It is shown that this method can be improved by considering the polarization of the core by the valence nucleon. This gives rise to some rearrangement energy which affects the single valence nucleon energy within the nucleus.
The Maxwell wave function of the photon
M. G. Raymer; Brian J. Smith
2006-04-24
James Clerk Maxwell unknowingly discovered a correct relativistic, quantum theory for the light quantum, forty-three years before Einstein postulated the photon's existence. In this theory, the usual Maxwell field is the quantum wave function for a single photon. When the non-operator Maxwell field of a single photon is second quantized, the standard Dirac theory of quantum optics is obtained. Recently, quantum-state tomography has been applied to experimentally determine photon wave functions.
Time symmetry in wave function collapse models
Daniel Bedingham
2015-02-25
A framework for wave function collapse models that is symmetric under time reversal is presented. Within this framework there are equivalent pictures of collapsing wave functions evolving in both time directions. The backwards-in-time Born rule can be broken by an initial condition on the Universe resulting in asymmetric behaviour. Similarly the forwards-in-time Born rule can in principle be broken by a final condition on the Universe.
The geometry of electron wave functions
Aminov, Yurii A
2013-02-28
To each wave function we assign a codimension-two submanifold in Euclidean space. We study the case of the wave function of a single electron in the hydrogen atom or other hydrogen-type atoms with quantum numbers n, l, m in detail. We prove theorems describing the behaviour of the scalar and sectional curvature of the constructed submanifold, depending on the quantum numbers. We also consider the external geometry of the submanifold. Bibliography: 9 titles.
Impact damage detection in composite panels using guided ultrasonic waves
NASA Astrophysics Data System (ADS)
Murat, Bibi Intan Suraya; Khalili, Pouyan; Fromme, Paul
2014-02-01
Composite materials such as carbon fiber reinforced panels offer many advantages for aerospace applications, e.g, good strength to weight ratio. However, impact during the operation and servicing of the aircraft can lead to barely visible and difficult to detect damage. Depending on the severity of the impact, fiber breakage or delaminations can be induced which reduce the functionality of the structure. Efficient structural health monitoring of such plate-like components can be achieved using guided ultrasonic waves propagating along the structure and covering critical areas. However, the guided wave propagation in such anisotropic and inhomogeneous materials needs to be understood from theory and verified experimentally to achieve sufficient coverage of the structure. Using noncontact laser interferometer measurements the guided wave propagation in carbon fiber reinforced panels was investigated experimentally. Good agreement with calculations using a full three-dimensional Finite Element (FE) model was achieved. Impact damage was induced in the composite panels and the guided wave scattering at the damage measured and quantified. Good agreement with predictions was found and barely visible impact damage in composite panels detected.
The Wave Function and Quantum Reality
Gao Shan
2011-03-28
We investigate the meaning of the wave function by analyzing the mass and charge density distributions of a quantum system. According to protective measurement, a charged quantum system has effective mass and charge density distributing in space, proportional to the square of the absolute value of its wave function. In a realistic interpretation, the wave function of a quantum system can be taken as a description of either a physical field or the ergodic motion of a particle. The essential difference between a field and the ergodic motion of a particle lies in the property of simultaneity; a field exists throughout space simultaneously, whereas the ergodic motion of a particle exists throughout space in a time-divided way. If the wave function is a physical field, then the mass and charge density will be distributed in space simultaneously for a charged quantum system, and thus there will exist gravitational and electrostatic self-interactions of its wave function. This not only violates the superposition principle of quantum mechanics but also contradicts experimental observations. Thus the wave function cannot be a description of a physical field but be a description of the ergodic motion of a particle. For the later there is only a localized particle with mass and charge at every instant, and thus there will not exist any self-interaction for the wave function. It is further argued that the classical ergodic models, which assume continuous motion of particles, cannot be consistent with quantum mechanics. Based on the negative result, we suggest that the wave function is a description of the quantum motion of particles, which is random and discontinuous in nature. On this interpretation, the square of the absolute value of the wave function not only gives the probability of the particle being found in certain locations, but also gives the probability of the particle being there. The suggested new interpretation of the wave function provides a natural realistic alternative to the orthodox interpretation, and it also implies that the de Broglie-Bohm theory and many-worlds interpretation are wrong and the dynamical collapse theories are in the right direction by admitting wavefunction collapse.
M. Beneke; Y. Kiyo; K. Schuller
2007-05-30
We obtain analytic expressions for the third-order corrections due to the strong interaction Coulomb potential to the S-wave Green function, energy levels and wave functions at the origin for arbitrary principal quantum number n. Together with the known non-Coulomb correction this results in the complete spectrum of S-states up to order alpha_s^5. The numerical impact of these corrections on the Upsilon spectrum and the top quark pair production cross section near threshold is estimated.
Zeqian Chen
2007-09-29
It is shown that von Neumann-Landau equation for wave functions can present a mathematical formalism of motion of quantum mechanics. The wave functions of von Neumann-Landau equation for a single particle are `bipartite', in which the associated Schr\\"{o}dinger's wave functions correspond to those `bipartite' wave functions of product forms. This formalism establishes a mathematical expression of wave-particle duality and that von Neumann's entropy is a quantitative measure of complementarity between wave-like and particle-like behaviors. Furthermore, this extension of Schr\\"{o}dinger's form suggests that collapses of Schr\\"{o}dinger's wave functions can be regarded as the simultaneous transition of the particle from many levels to one.
Weak Measurement and (Bohmian) Conditional Wave Functions
Travis Norsen; Ward Struyve
2013-10-07
It was recently pointed out (and demonstrated experimentally) by Lundeen et al. that the wave function of a particle (more precisely, the wave function possessed by each member of an ensemble of identically-prepared particles) can be "directly measured" using weak measurement. Here it is shown that if this same technique is applied, with appropriate post-selection, to one particle from a (perhaps entangled) multi-particle system, the result is precisely the so-called "conditional wave function" of Bohmian mechanics. Thus, a plausibly operationalist method for defining the wave function of a quantum mechanical sub-system corresponds to the natural definition of a sub-system wave function which Bohmian mechanics (uniquely) makes possible. Similarly, a weak-measurement-based procedure for directly measuring a sub-system's density matrix should yield, under appropriate circumstances, the Bohmian "conditional density matrix" as opposed to the standard reduced density matrix. Experimental arrangements to demonstrate this behavior -- and also thereby reveal the non-local dependence of sub-system state functions on distant interventions -- are suggested and discussed.
The evolution of oscillator wave functions
Mark Andrews
2015-09-20
We consider some of the methods that can be used to reveal the general features of how wave functions evolve with time in the harmonic oscillator. We first review the periodicity properties over each multiple of a quarter of the classical period of oscillation. Then we show that any wave function can be simply transformed so that its centroid, defined by the expectation values of position and momentum, remains at rest at the center of the oscillator. This implies that we need only consider the evolution of this restricted class of wave functions; the evolution of all others can be reduced to these. The evolution of the spread in position $\\Delta_x$ and momentum $\\Delta_p$ throws light on energy and uncertainty and on squeezed and coherent states. Finally we show that any wave function can be transformed so that $\\Delta_x$ and $\\Delta_p$ do not change with time and that the evolution of all wave functions can easily be found from the evolution of those at rest at the origin with unchanging $\\Delta_x$ and $\\Delta_p$.
Faddeev wave function decomposition using bipolar harmonics
NASA Astrophysics Data System (ADS)
Friar, J. L.; Tomusiak, E. L.; Gibson, B. F.; Payne, G. L.
1981-08-01
The standard partial wave (channel) representation for the Faddeev solution to the Schrödinger equation for the ground state of 3 nucleons is written in terms of functions which couple the interacting pair and spectator angular momenta to give S, P, and D waves. For each such coupling there are three terms, one for each of the three cyclic permutations of the nucleon coordinates. A series of spherical harmonic identities is developed which allows writing the Faddeev solution in terms of a basis set of 5 bipolar harmonics: 1 for S waves; 1 for P waves; and 3 for D waves. The choice of a D-wave basis is largely arbitrary, and specific choices correspond to the decomposition schemes of Derrick and Blatt, Sachs, Gibson and Schiff, and Bolsterli and Jezak. The bipolar harmonic form greatly simplifies applications which utilize the wave function, and we specifically discuss the isoscalar charge (or mass) density and the 3He Coulomb energy. [NUCLEAR STRUCTURE Three-body problem, classification of states.
Investigating wave data from the FAST satellite by reconstructing the wave distribution function
California at Berkeley, University of
Investigating wave data from the FAST satellite by reconstructing the wave distribution function G cross spectra and autospectra computed from the data, we reconstruct the wave distribution function (WDF function, wave propagation 1. Introduction [2] Waves with frequencies at or slightly above the local proton
Distributed Phase Acquisition in a Wave Function
Robert Englman; Asher Yahalom
2011-01-22
A separable $x-y$ model is solved for a specialized vector potential (no magnetic and weak electric fields) penetrating slowly\\textbf{,} adiabatically into and across a rectangular box to which an electron is confined. The time-dependent Schr\\"odinger equation has adiabatic solutions, in which gradual phase acquisitions occur for {\\it parts} of the electronic wave function. For a closed trajectory of the source, the initial and after-return wave functions are shown to be simultaneously co-degenerate solutions of the Hamiltonian, which situation repeats itself for further cyclic motion of the source.
Measurement of Oblique Impact-generated Shear Waves
NASA Technical Reports Server (NTRS)
Dahl, J. M.; Schultz, P. H.
2001-01-01
Experimental strain measurements reveal that oblique impacts can generate shear waves with displacements as large as those in the P-wave. Large oblique impacts may thus be more efficient sources of surface disruption than vertical impacts. Additional information is contained in the original extended abstract.
On the Role of Shock Wave Reflections in Impact Cratering
NASA Astrophysics Data System (ADS)
Bertoglio, O.
2015-07-01
When the downward impact shockwave meets a rock discontinuity, an upward reflected pressure wave is created. When travelling through the crater fill deposits, this wave projects upwards the shattered rocks which so may contribute to the rim creation.
The wave function of a gravitating shell
V. I. Dokuchaev; S. V. Chernov
2010-10-01
We have calculated a discrete spectrum and found an exact analytical solution in the form of Meixner polynomials for the wave function of a thin gravitating shell in the Reissner-Nordstrom geometry. We show that there is no extreme state in the quantum spectrum of the gravitating shell, as in the case of extreme black hole.
Multifractal wave functions of simple quantum maps
John Martin; Ignacio Garcia-Mata; Olivier Giraud; Bertrand Georgeot
2010-07-08
We study numerically multifractal properties of two models of one-dimensional quantum maps, a map with pseudointegrable dynamics and intermediate spectral statistics, and a map with an Anderson-like transition recently implemented with cold atoms. Using extensive numerical simulations, we compute the multifractal exponents of quantum wave functions and study their properties, with the help of two different numerical methods used for classical multifractal systems (box-counting method and wavelet method). We compare the results of the two methods over a wide range of values. We show that the wave functions of the Anderson map display a multifractal behavior similar to eigenfunctions of the three-dimensional Anderson transition but of a weaker type. Wave functions of the intermediate map share some common properties with eigenfunctions at the Anderson transition (two sets of multifractal exponents, with similar asymptotic behavior), but other properties are markedly different (large linear regime for multifractal exponents even for strong multifractality, different distributions of moments of wave functions, absence of symmetry of the exponents). Our results thus indicate that the intermediate map presents original properties, different from certain characteristics of the Anderson transition derived from the nonlinear sigma model. We also discuss the importance of finite-size effects.
The nucleon wave function at the origin
Michael Gruber
2011-04-05
We calculate the next-to-leading order perturbative corrections to the SVZ sum rules for the coupling f_N, the nucleon leading twist wave function at the origin. The results are compared to the established Ioffe sum rules and also to lattice QCD simulations.
Impact Seismology: A Search for Primary Pressure Waves Following Impacts A and H
NASA Astrophysics Data System (ADS)
Mosser, B.; Galdemard, P.; Lagage, P.; Pantin, E.; Sauvage, M.; Lognonné, P.; Gautier, D.; Billebaud, F.; Livengood, T.; Käufl, H. U.
1996-06-01
This paper reports part of the seismic observations performed after the impacts of Shoemaker-Levy 9 fragments A and H with the mid-IR camera TIMMI at the ESO 3.6-m telescope. Hodograms have been computed to search for the seismic signature of the primary waves crossing the planet within 2 hr following each impact. The hodogram analysis has been unable to detect any seismic signal. In order to put a limit on the kinetic energy of the fragments, the synthetic thermal signature of the primary wave has been calculated as a function of the incident energy, according to theoretical simulations, and taking into account observational conditions such as the point spread function. The non-detection implies that the kinetic energy of impacts A and H was less than 2 × 1021J, within the frame of the theoretical simulation of Lognonnéet al.(Lognonné, Ph., B. Mosser, and F. Dahlen 1994.Icarus110, 180-195.). The error bar is as large as one order of magnitude, according to other simulations. The seismic wave should have contributed to a non-negligible part of the heating of the region surrounding the impacts, but it is not yet possible to measure its contribution.
Wave Functions 2.1 Classical and Quantum Particles
Griffiths, Robert B.
Chapter 2 Wave Functions 2.1 Classical and Quantum Particles In classical Hamiltonian mechanics corresponds to x 1 # x # x 2 . 9 #12; 10 CHAPTER 2. WAVE FUNCTIONS A quantum particle at a single instant of time is described by a wave function #(r), a complex function of position r. Again in the interests
Wave Functions 2.1 Classical and Quantum Particles
Griffiths, Robert B.
Chapter 2 Wave Functions 2.1 Classical and Quantum Particles In classical Hamiltonian mechanics to x1 x x2. 9 #12;10 CHAPTER 2. WAVE FUNCTIONS A quantum particle at a single instant of time is described by a wave function (r), a complex function of position r. Again in the interests of simplicity we
Continuous Observations and the Wave Function Collapse
A. Marchewka; Z. Schuss
2011-03-13
We propose to modify the collapse axiom of quantum measurement theory by replacing the instantaneous with a continuous collapse of the wave function in finite time $\\tau$. We apply it to coordinate measurement of a free quantum particle that is initially confined to a domain $D\\subset\\rR^d$ and is observed continuously by illuminating $\\rR^d-D$. The continuous collapse axiom (CCA) defines the post-measurement wave function (PMWF)in $D$ after a negative measurement as the solution of Schr\\"odinger's equation at time $\\tau$ with instantaneously collapsed initial condition and homogeneous Dirichlet condition on the boundary of $D$. The CCA applies to all cases that exhibit the Zeno effect. It rids quantum mechanics of the unphysical artifacts caused by instantaneous collapse and introduces no new artifacts.
Exact Wave Functions for Generalized Harmonic Oscillators
Nathan Lanfear; Raquel M. Lopez; Sergei K. Suslov
2011-07-20
We transform the time-dependent Schroedinger equation for the most general variable quadratic Hamiltonians into a standard autonomous form. As a result, the time-evolution of exact wave functions of generalized harmonic oscillators is determined in terms of solutions of certain Ermakov and Riccati-type systems. In addition, we show that the classical Arnold transformation is naturally connected with Ehrenfest's theorem for generalized harmonic oscillators.
STUDY OF BLAST WAVE IMPACT ON CONCRETE AJIT GEEVARGHESE JOHN
Texas at Arlington, University of
to buildings that often collapse before evacuation is possible. These blast waves subject the buildings wave created in a shock tube and a reasonably realistic simulation of blast loading on structures canSTUDY OF BLAST WAVE IMPACT ON CONCRETE by AJIT GEEVARGHESE JOHN Presented to the Faculty
Abhayapala, Thushara D.
GENERALIZED HERGLOTZ WAVE FUNCTIONS FOR MODELLING WIRELESS NEARFIELD MULTIPATHSCATTERING. This model gen- eralizes the Herglotz Wave Function, which is an important tool in the study of inverse. Herglotz wave functions primarily find use in inverse scattering problems where it is natural to find
Primordial gravitational waves and the collapse of the wave function
NASA Astrophysics Data System (ADS)
León, Gabriel; Kraiselburd, Lucila; Landau, Susana J.
2015-10-01
The self-induced collapse hypothesis was introduced by D. Sudarsky and collaborators to explain the origin of cosmic structure from a perfect isotropic and homogeneous universe during the inflationary regime. In this paper, we calculate the power spectrum for the tensor modes, within the semiclassical gravity approximation, with the additional hypothesis of a generic self-induced collapse of the inflaton's wave function; we also compute an estimate for the tensor-to-scalar ratio. Based on this calculation, we show that the considered proposal exhibits a strong suppression of the tensor modes amplitude; nevertheless, the corresponding amplitude is still consistent with the joint BICEP/KECK and Planck Collaboration's limit on the tensor-to-scalar ratio.
Direct impacts of waves on tropical cold point tropopause temperature
NASA Astrophysics Data System (ADS)
Kim, Ji-Eun; Alexander, M. Joan
2015-03-01
Cold point tropopause temperature is a key regulator of cirrus clouds and stratospheric water vapor, which have significant impacts on the Earth's radiation budget and climate. Using tropical radiosonde observations, we show that waves in the tropical tropopause layer lower cold point temperature by 1.6 K on average relative to the seasonal mean. Furthermore, wave activity in the tropical tropopause layer has not been constant over the last 2.5 decades, altering the magnitude of the wave impacts on cold point temperature at a decadal scale. The change in the direct wave impact is partially (~20-30%) responsible for the sudden decrease in cold point temperature and stratospheric water vapor at the end of 2000, which has not been fully explained by changes in the Brewer-Dobson circulation. We further show that these wave impacts are not well represented in reanalysis data.
Covariance constraints for light front wave functions
Müller, Dieter
2015-01-01
Light front wave functions (LFWFs) are often utilized to model parton distributions and form factors where their transverse and longitudinal momenta are tied to each other in some manner that is often guided by convenience. On the other hand, the cross talk of transverse and longitudinal momenta is governed by Poincar\\'e symmetry and thus popular LFWF models are often not usable to model more intricate quantities such as generalized parton distributions. In this contribution a closer look to this issue is given and it is shown how to overcome the issue for two--body LFWFs.
Lanczos steps to improve variational wave functions
NASA Astrophysics Data System (ADS)
Becca, Federico; Hu, Wen-Jun; Iqbal, Yasir; Parola, Alberto; Poilblanc, Didier; Sorella, Sandro
2015-09-01
Gutzwiller-projected fermionic states can be efficiently implemented within quantum Monte Carlo calculations to define extremely accurate variational wave functions for Heisenberg models on frustrated two-dimensional lattices, not only for the ground state but also for low-energy excitations. The application of few Lanczos steps on top of these states further improves their accuracy, allowing calculations on large clusters. In addition, by computing both the energy and its variance, it is possible to obtain reliable estimations of exact results. Here, we report the cases of the frustrated Heisenberg models on square and Kagome lattices.
Adiabatic corrections to density functional theory energies and wave functions.
Mohallem, José R; Coura, Thiago de O; Diniz, Leonardo G; de Castro, Gustavo; Assafrão, Denise; Heine, Thomas
2008-09-25
The adiabatic finite-nuclear-mass-correction (FNMC) to the electronic energies and wave functions of atoms and molecules is formulated for density-functional theory and implemented in the deMon code. The approach is tested for a series of local and gradient corrected density functionals, using MP2 results and diagonal-Born-Oppenheimer corrections from the literature for comparison. In the evaluation of absolute energy corrections of nonorganic molecules the LDA PZ81 functional works surprisingly better than the others. For organic molecules the GGA BLYP functional has the best performance. FNMC with GGA functionals, mainly BLYP, show a good performance in the evaluation of relative corrections, except for nonorganic molecules containing H atoms. The PW86 functional stands out with the best evaluation of the barrier of linearity of H2O and the isotopic dipole moment of HDO. In general, DFT functionals display an accuracy superior than the common belief and because the corrections are based on a change of the electronic kinetic energy they are here ranked in a new appropriate way. The approach is applied to obtain the adiabatic correction for full atomization of alcanes C(n)H(2n+2), n = 4-10. The barrier of 1 mHartree is approached for adiabatic corrections, justifying its insertion into DFT. PMID:18537228
Variational wave functions for homogenous Bose systems
Sueto, Andras; Szepfalusy, Peter
2008-02-15
We study variational wave functions of the product form, factorizing according to the wave vectors k, for the ground state of a system of bosons interacting via positive pair interactions with a positive Fourier transform. Our trial functions are members of different orthonormal bases in Fock space. Each basis contains a quasiparticle vacuum state and states with an arbitrary finite number of quasiparticles. One of the bases is that of Valatin and Butler (VB), introduced fifty years ago and parametrized by an infinite set of variables determining Bogoliubov's canonical transformation for each k. In another case, inspired by Nozieres and Saint James the canonical transformation for k=0 is replaced by a shift in the creation/annihilation operators. For the VB basis we prove that the lowest energy is obtained in a state with {approx}{radical}(volume) quasiparticles in the zero mode. The number of k=0 physical particles is of the order of the volume and its fluctuation is anomalously large, resulting in an excess energy. The same fluctuation is normal in the second type of optimized bases, the minimum energy is smaller and is attained in a vacuum state. Associated quasiparticle theories and questions about the gap in their spectrum are also discussed.
Impact of Functionally Graded Cylinders: Theory
NASA Technical Reports Server (NTRS)
Aboudi, Jacob; Pindera, Marek-Jerzy; Arnold, S. M. (Technical Monitor)
2001-01-01
This final report summarizes the work funded under the Grant NAG3-2411 during the 04/05/2000-04/04/2001 period. The objective of this one-year project was to generalize the theoretical framework of the two-dimensional higher-order theory for the analysis of cylindrical functionally graded materials/structural components employed in advanced aircraft engines developed under past NASA Glenn funding. The completed generalization significantly broadens the theory's range of applicability through the incorporation of dynamic impact loading capability into its framework. Thus, it makes possible the assessment of the effect of damage due to fuel impurities, or the presence of submicron-level debris, on the life of functionally graded structural components. Applications involving advanced turbine blades and structural components for the reusable-launch vehicle (RLV) currently under development will benefit from the completed work. The theory's predictive capability is demonstrated through a numerical simulation of a one-dimensional wave propagation set up by an impulse load in a layered half-plane. Full benefit of the completed generalization of the higher-order theory described in this report will be realized upon the development of a related computer code.
Breaking wave impact on a slender horizontal cylinder
Prasad, S.; Isaacson, M.; Chan, E.S.
1994-12-31
The present paper describes the results of an experimental study of impact forces due to plunging wave action on a horizontal circular cylinder located near the still water level. The vertical and horizontal components of the impact force on the cylinder due to a single plunging wave have been measured for 3 elevations of the cylinder, and 6 locations of wave breaking relative to the horizontal location of the cylinder. A video record of the impact process has been used to estimate the kinematics of the wave and plunging jet prior to impact. The force measurements have been corrected for the dynamic response of the cylinder, and analyzed to obtain slamming coefficients and rise times. It is observed that the cylinder elevation and its horizontal location have a significant effect on the peak impact force. The magnitude of the impact force due to a breaking wave is 4 to 20 times greater than that due to a regular non-breaking wave of similar height and period. In addition to the fluid velocity, the curvature of the water surface has a noticeable effect on the peak impact force.
A Hammer-Impact, Aluminum, Shear-Wave Seismic Source
Haines, Seth S.
2007-01-01
Near-surface seismic surveys often employ hammer impacts to create seismic energy. Shear-wave surveys using horizontally polarized waves require horizontal hammer impacts against a rigid object (the source) that is coupled to the ground surface. I have designed, built, and tested a source made out of aluminum and equipped with spikes to improve coupling. The source is effective in a variety of settings, and it is relatively simple and inexpensive to build.
Intercellular Ca2+ Waves: Mechanisms and Function
Sanderson, Michael J.
2012-01-01
Intercellular calcium (Ca2+) waves (ICWs) represent the propagation of increases in intracellular Ca2+ through a syncytium of cells and appear to be a fundamental mechanism for coordinating multicellular responses. ICWs occur in a wide diversity of cells and have been extensively studied in vitro. More recent studies focus on ICWs in vivo. ICWs are triggered by a variety of stimuli and involve the release of Ca2+ from internal stores. The propagation of ICWs predominately involves cell communication with internal messengers moving via gap junctions or extracellular messengers mediating paracrine signaling. ICWs appear to be important in both normal physiology as well as pathophysiological processes in a variety of organs and tissues including brain, liver, retina, cochlea, and vascular tissue. We review here the mechanisms of initiation and propagation of ICWs, the key intra- and extracellular messengers (inositol 1,4,5-trisphosphate and ATP) mediating ICWs, and the proposed physiological functions of ICWs. PMID:22811430
String wave function across a Kasner singularity
Copeland, Edmund J.; Niz, Gustavo; Turok, Neil
2010-06-15
A collision of orbifold planes in 11 dimensions has been proposed as an explanation of the hot big bang. When the two planes are close to each other, the winding membranes become the lightest modes of the theory, and can be effectively described in terms of fundamental strings in a ten-dimensional background. Near the brane collision, the 11-dimensional metric is a Euclidean space times a 1+1-dimensional Milne universe. However, one may expect small perturbations to lead into a more general Kasner background. In this paper we extend the previous classical analysis of winding membranes to Kasner backgrounds, and using the Hamiltonian equations, solve for the wave function of loops with circular symmetry. The evolution across the singularity is regular, and explained in terms of the excitement of higher oscillation modes. We also show there is finite particle production and unitarity is preserved.
Nonlinear Trivelpiece-Gould waves: Frequency, functional form, and stability
NASA Astrophysics Data System (ADS)
Dubin, D. H. E.; Ashourvan, A.
2015-10-01
This paper considers the frequency, spatial form, and stability of nonlinear Trivelpiece-Gould (TG) waves on a cylindrical plasma column of length L and radius rp, treating both traveling waves and standing waves, and focussing on the regime of experimental interest in which L /rp?1 . In this regime, TG waves are weakly dispersive, allowing strong mode-coupling between Fourier harmonics. The mode coupling implies that linear theory for such waves is a poor approximation even at fairly small amplitude, and nonlinear theories that include a small number of harmonics, such as three-wave parametric resonance theory, also fail to fully capture the stability properties of the system. It is found that nonlinear standing waves suffer jumps in their functional form as their amplitude is varied continuously. The jumps are caused by nonlinear resonances between the standing wave and nearly linear waves whose frequencies and wave numbers are harmonics of the standing wave. Also, the standing waves are found to be unstable to a multi-wave version of three-wave parametric resonance, with an amplitude required for instability onset that is much larger than expected from three wave theory. It is found that traveling waves are linearly stable for all amplitudes that could be studied, in contradiction to three-wave theory.
POSSIBLE EXPERIMENTS ON WAVE FUNCTION LOCALIZATION DUE TO COMPTON SCATTERING
Aleksandrov, Alexander V; Danilov, Viatcheslav V; Gorlov, Timofey V; Liu, Yun; Shishlo, Andrei P; Nagaitsev,
2013-01-01
The reduction of a particle s wave function in the process of radiation or light scattering is a longstanding problem. Its solution will give a clue on processes that form, for example, wave functions of electrons constantly emitting synchrotron radiation quanta in storage rings. On a more global scale, it may shed light on wave function collapse due to the process of measurement. In this paper we consider various experimental options using Fermilab electron beams and a possible electron beam from the SNS linac and lasers to detect electron wave function change due to Compton scattering.
Impact of simulated heat waves on soybean physiology and yield
Technology Transfer Automated Retrieval System (TEKTRAN)
With increases in mean global temperatures and associated climate change, extreme temperature events are predicted to increase in both intensity and frequency. Despite the clearly documented negative public health impacts of heat waves, the impact on physiology and yields of key agricultural species...
Correlational entropy and complexity of wave functions
NASA Astrophysics Data System (ADS)
Brown, B. A.; Zelevinsky, V.; Sokolov, V.
1997-04-01
The eigenfunctions |?> of a realistic quantum system are complicated superpositions of simple basis configurations k>, |?>=sum_kC^?k |k>. The complexity of wave functions, as one of generic signatures of quantum chaos, was analyzed in (V.Zelevinsky, B.A.Brown, N.Frazier and M.Horoi, Phys. Rep. 276), 85 (1996) with the aid of basis-dependent informational entropy of an eigenstate, S^?=-sum_k(C^?_k)^2ln(C^?_k)^2. Here we suggest an invariant correlational entropy as a complementary feature of the process of mixing and stochastization. We find the evolution of |?> as a function of a relevant physical parameter ? and construct the density matrix ?^?_kk' by averaging the product C^?_k(?)C^?*_k'(?) over the interval of ?. The correlational entropy is S^?_c=-Tr(?^?ln?^?). We show the sensitivity of S^?c to level crossings in the given interval of ?. The behavior of S^?c in the nuclear shell model is studied. The analytical solution for S_c^? of an oscillator in a random electric field coincides with the entropy of the equilibrium Planck distribution.
Holographic Wave Functions, Meromorphization and Counting Rules
Anatoly Radyushkin
2006-05-10
We study the large-Q{sup 2} behavior of the meson form factor F{sub M} (Q{sup 2}) constructed using the holographic light-front wave functions proposed recently by Brodsky and de Teramond. We show that this model can be also obtained within the Migdal's regularization approach (''meromorphization''), if one applies it to 3-point function for scalar currents made of scalar quarks. We found that the asymptotic 1/Q{sup 2} behavior of F{sub M} (Q{sup 2}) is generated by soft Feynman mechanism rather than by short distance dynamics, which causes very late onset of the 1/Q{sup 2} asymptotic behavior. It becomes visible only for unaccessible momenta Q{sup 2} {approx}> 10, GeV{sup 2}. Using meromorphization for spin-1/2 quarks, we demonstrated that resulting form factor F{sup spinor}{sub M} (Q{sup 2}) has 1/Q{sup 4} asymptotic behavior. Now, owing to the late onset of this asymptotic pattern, F{sup spinor}{sub M} (Q{sup 2}) imitates the 1/Q{sup 2} behavior in the few GeV{sup 2} region.
Completeness of the Coulomb scattering wave functions
A. M. Mukhamedzhanov; M. Akin
2006-02-01
Completeness of the eigenfunctions of a self-adjoint Hamiltonian, which is the basic ingredient of quantum mechanics, plays an important role in nuclear reaction and nuclear structure theory. However, until now, there was no a formal proof of the completeness of the eigenfunctions of the two-body Hamiltonian with the Coulomb interaction. Here we present the first formal proof of the completeness of the two-body Coulomb scattering wave functions for repulsive unscreened Coulomb potential. To prove the completeness we use the Newton's method [R. Newton, J. Math Phys., 1, 319 (1960)]. The proof allows us to claim that the eigenfunctions of the two-body Hamiltonian with the potential given by the sum of the repulsive Coulomb plus short-range (nuclear) potentials also form a complete set. It also allows one to extend the Berggren's approach of modification of the complete set of the eigenfunctions by including the resonances for charged particles. We also demonstrate that the resonant Gamow functions with the Coulomb tail can be regularized using Zel'dovich's regularization method.
Guided ultrasonic waves for impact damage detection in composite panels
NASA Astrophysics Data System (ADS)
Murat, B. I. S.; Khalili, P.; Fromme, P.
2014-03-01
Carbon fiber laminate composites, consisting of layers of polymer matrix reinforced with high strength carbon fibers, are increasingly employed for aerospace structures. They offer advantages for aerospace applications, e.g., good strength to weight ratio. However, impact during the operation and servicing of the aircraft can lead to barely visible and difficult to detect damage. Depending on the severity of the impact, fiber and matrix breakage or delaminations can occur, reducing the load carrying capacity of the structure. Efficient structural health monitoring of composite panels can be achieved using guided ultrasonic waves propagating along the structure. Impact damage was induced in the composite panels using standard drop weight procedures. The guided wave scattering at the impact damage was measured using a noncontact laser interferometer, quantified, and compared to baseline measurements on undamaged composite panels. Significant scattering of the first anti-symmetrical (A0) guided wave mode was observed, allowing for the detection of barely visible impact damage. The guided wave scattering was modeled using full three-dimensional Finite Element (FE) simulations, and the influence of the different damage mechanisms investigated. Good agreement between experiments and predictions was found. The sensitivity of guided waves for the detection of barely visible impact damage in composite panels has been verified.
Six Impossible Things: Fractional Charge From Laughlin's Wave Function
Shrivastava, Keshav N.
2010-12-23
The Laughlin's wave function is found to be the zero-energy ground state of a {delta}-function Hamiltonian. The finite negative value of the ground state energy which is 91 per cent of Wigner value, can be obtained only when Coulomb correlations are introduced. The Laughlin's wave function is of short range and it overlaps with that of the exact wave functions of small (number of electrons 2 or 5) systems. (i) It is impossible to obtain fractional charge from Laughlin's wave function. (ii) It is impossible to prove that the Laughlin's wave function gives the ground state of the Coulomb Hamiltonian. (iii) It is impossible to have particle-hole symmetry in the Laughlin's wave function. (iv) It is impossible to derive the value of m in the Laughlin's wave function. The value of m in {psi}{sub m} can not be proved to be 3 or 5. (v) It is impossible to prove that the Laughlin's state is incompressible because the compressible states are also likely. (vi) It is impossible for the Laughlin's wave function to have spin. This effort is directed to explain the experimental data of quantum Hall effect in GaAs/AlGaAs.
Photon wave functions, wave-packet quantization of light, and coherence theory
Brian J. Smith; M. G. Raymer
2007-12-09
The monochromatic Dirac and polychromatic Titulaer-Glauber quantized field theories (QFTs) of electromagnetism are derived from a photon-energy wave function in much the same way that one derives QFT for electrons, that is, by quantization of a single-particle wave function. The photon wave function and its equation of motion are established from the Einstein energy-momentum-mass relation, assuming a local energy density. This yields a theory of photon wave mechanics (PWM). The proper Lorentz-invariant single-photon scalar product is found to be non-local in coordinate space, and is shown to correspond to orthogonalization of the Titulaer-Glauber wave-packet modes. The wave functions of PWM and mode functions of QFT are shown to be equivalent, evolving via identical equations of motion, and completely describe photonic states. We generalize PWM to two or more photons, and show how to switch between the PWM and QFT viewpoints. The second-order coherence tensors of classical coherence theory and the two-photon wave functions are shown to propagate equivalently. We give examples of beam-like states, which can be used as photon wave functions in PWM, or modes in QFT. We propose a practical mode converter based on spectral filtering to convert between wave packets and their corresponding biorthogonal dual wave packets.
Exclusive processes of charmonium production and charmonium wave functions
Braguta, V. V. Likhoded, A. K. Luchinsky, A. V.
2012-01-15
Results obtained by studying the properties of the leading-twist wave functions for the S- and P-wave states of charmonia are presented. Wave-function models that can be used to calculate various processes involving the production of these mesons were constructed on the basis of these investigations. Calculations for some exclusive processes of charmonium production were performed within the models in question.
Exponentially Accurate Semiclassical Tunneling Wave Functions in One Dimension
Vasile Gradinaru; George A. Hagedorn; Alain Joye
2010-03-17
We study the time behavior of wave functions involved in tunneling through a smooth potential barrier in one dimension in the semiclassical limit. We determine the leading order component of the wave function that tunnels. It is exponentially small in $1/\\hbar$. For a wide variety of incoming wave packets, the leading order tunneling component is Gaussian for sufficiently small $\\hbar$. We prove this for both the large time asymptotics and for moderately large values of the time variable.
Gravity-related wave function collapse: Is superfluid He exceptional?
Lajos Diósi
2013-02-21
The gravity-related model of spontaneous wave function collapse, a longtime hypothesis, damps the massive Schr\\"odinger Cat states in quantum theory. We extend the hypothesis and assume that spontaneous wave function collapses are responsible for the emergence of Newton interaction. Superfluid helium would then show significant and testable gravitational anomalies.
Detecting wave function collapse without prior knowledge
NASA Astrophysics Data System (ADS)
Cowan, Charles Wesley; Tumulka, Roderich
2015-08-01
We are concerned with the problem of detecting with high probability whether a wave function has collapsed or not, in the following framework: A quantum system with a d-dimensional Hilbert space is initially in state ?; with probability 0 < p < 1, the state collapses relative to the orthonormal basis b1, …, bd. That is, the final state ?' is random, it is ? with probability 1 - p and bk (up to a phase) with p times Born's probability || ? 2 . Now an experiment on the system in state ?' is desired that provides information about whether or not a collapse has occurred. Elsewhere [C. W. Cowan and R. Tumulka, J. Phys. A: Math. Theor. 47, 195303 (2014)], we identify and discuss the optimal experiment in case that ? is either known or random with a known probability distribution. Here, we present results about the case that no a priori information about ? is available, while we regard p and b1, …, bd as known. For certain values of p, we show that the set of ?s for which any experiment E is more reliable than blind guessing is at most half the unit sphere; thus, in this regime, any experiment is of questionable use, if any at all. Remarkably, however, there are other values of p and experiments E such that the set of ?s for which E is more reliable than blind guessing has measure greater than half the sphere, though with a conjectured maximum of 64% of the sphere.
Plausible Suggestion for a Deterministic Wave Function
Petra Schulz
2006-09-26
A deterministic axial vector model for photons is presented which is suitable also for particles. During a rotation around an axis the deterministic wave function a has the following form a = ws r exp(+-i wb t). ws is either the axial or scalar spin rotation frequency (the latter is proportional to the mass), r radius of the orbit (also amplitude of a vibration arising later from the interaction by fusing of two oppositely circling photons), wb orbital angular frequency (proportional to the velocity) and t time. "+" before the imaginary i means a right-handed and "-" a left-handed rotation. An interaction happens if particles (including the photons) meet themselves through collision and melt together. ----- Es wird ein deterministisches Drehvektor-Modell fuer Photonen vorgestellt, das auch fuer Teilchen geeignet ist. Bei einer Kreisbewegung um eine Achse hat die deterministische Wellenfunktion a die folgende Form a = ws r exp(+-i wb t). Dabei bedeuten ws entweder die axiale oder die skalare Spin-Kreisfrequenz (letztere ist proportional der Masse), r Radius der Kreisbahn (auch Amplitude einer sich spaeter durch Wechselwirkung ergebenden Schwingung aus zwei entgegengesetzt kreisenden verschmolzenen Photonen), wb Kreisbahn-Frequenz (ein Mass fuer die Bahngeschwindigkeit) und t Zeit. Das "+" vor dem imaginaeren i bedeutet eine rechtshaendige und das "-" eine linkshaendige Rotation. Eine Wechselwirkung tritt ein, wenn sich Teilchen einschliesslich der Photonen durch Stossprozesse begegnen und dabei verschmelzen.
Electron wave-functions in a magnetic field
D. K. Sunko
2013-04-04
The problem of a single electron in a magnetic field is revisited from first principles. It is shown that the standard quantization, used by Landau, is inconsistent for this problem, whence Landau's wave functions spontaneously break the gauge symmetry of translations in the plane. Because of this Landau's (and Fock's) wave functions have a spurious second quantum number. The one-body wave function of the physical orbit, with only one quantum number, is derived, and expressed as a superposition of Landau's wave functions. Conversely, it is shown that Landau's wave functions are a limiting case of physical solutions of a different problem, where two quantum numbers naturally appear. When the translation gauge symmetry is respected, the degeneracy related to the choice of orbit center does not appear in the one-body problem.
Best Slater approximation of a fermionic wave function
Alex D. Gottlieb; Norbert J. Mauser; J. M. Zhang
2015-10-26
We study the best Slater approximation of an $N$-fermion wave function analytically. That is, we seek the Slater determinant (constructed out of $N$ orthonormal single-particle orbitals) wave function having largest overlap with a given $N$-fermion wave function. Some simple lemmas have been established and their usefulness is demonstrated on some structured states, such as the GHZ state. In the simplest nontrivial case of three fermions in six orbitals, which the celebrated Borland-Dennis discovery is about, the best Slater approximation wave function is proven to be built out of the natural orbitals in an interesting way. We also show that the Hadamard inequality is useful for finding the best Slater approximation of some special target wave functions.
Effect of Forcing Function on Nonlinear Acoustic Standing Waves
NASA Technical Reports Server (NTRS)
Finkheiner, Joshua R.; Li, Xiao-Fan; Raman, Ganesh; Daniels, Chris; Steinetz, Bruce
2003-01-01
Nonlinear acoustic standing waves of high amplitude have been demonstrated by utilizing the effects of resonator shape to prevent the pressure waves from entering saturation. Experimentally, nonlinear acoustic standing waves have been generated by shaking an entire resonating cavity. While this promotes more efficient energy transfer than a piston-driven resonator, it also introduces complicated structural dynamics into the system. Experiments have shown that these dynamics result in resonator forcing functions comprised of a sum of several Fourier modes. However, previous numerical studies of the acoustics generated within the resonator assumed simple sinusoidal waves as the driving force. Using a previously developed numerical code, this paper demonstrates the effects of using a forcing function constructed with a series of harmonic sinusoidal waves on resonating cavities. From these results, a method will be demonstrated which allows the direct numerical analysis of experimentally generated nonlinear acoustic waves in resonators driven by harmonic forcing functions.
Pain's Impact on Adaptive Functioning
ERIC Educational Resources Information Center
Breau, L. M.; Camfield, C. S.; McGrath, P. J.; Finley, G. A.
2007-01-01
Background: Pain interferes with the functioning of typical children, but no study has examined its effect on children with pre-existing intellectual disabilities (ID). Methods: Caregivers of 63 children observed their children for 2-h periods and recorded in 1-week diaries: pain presence, cause, intensity and duration. Caregivers also recorded…
Wave-particle duality and `bipartite' wave functions for a single particle
Zeqian Chen
2006-09-12
It is shown that `bipartite' wave functions can present a mathematical formalism of quantum theory for a single particle, in which the associated Schr\\"{o}dinger's wave functions correspond to those `bipartite' wave functions of product forms. This extension of Schr\\"{o}dinger's form establishes a mathematical expression of wave-particle duality and that von Neumann's entropy is a quantitative measure of complementarity between wave-like and particle-like behaviors. In particular, this formalism suggests that collapses of Schr\\"{o}dinger's wave functions can be regarded as the simultaneous transition of the particle from many levels to one. Our results shed considerable light on the basis of quantum mechanics, including quantum measurement.
Waves in Periodic Dissipative Laminate Metamaterial Generated by Plate Impact
NASA Astrophysics Data System (ADS)
Franco Navarro, Pedro; Benson, David; Nesterenko, Vitali
2015-06-01
Waves generated by plate impact loading of Al/W laminates with different size of cell were investigated numerically depending on the impactor/cell mass ratio. The materials model took into account viscoplastic behavior of materials. It was observed that this mass ratio has a direct impact on the structure of stress pulses traveling through the composite. At the small impactor/cell mass ratio travelling waves closely resembling solitary waves were quickly formed near the impacted surface. They propagate as quasistationary weakly attenuating localized pulses. The properties of these pulses were satisfactory described based on a theoretical model using dispersive and nonlinear parameters of the materials similar to solitary solutions for the Korteweg-de Vries equation (KdV). The temperature at given pressure at the maximum is dramatically different then the temperature corresponding to the shock wave at the same pressure reflecting a different paths of loading. Increase of impactor/cell mass ratio results in the train of solitary like pulses which number increased with the increase of the impactor/cell mass ratio. At large impactor/cell mass ratio oscillatory stationary shock waves were formed. The leading front of these stationary shock waves was closely described by a solitary like pulse observed at small impactor/cell mass ratio. One of the authors (PFN) was supported by UCMexus Fellowship
The small $K ?$ component in the $K^*$ wave functions
C. W. Xiao; F. Aceti; M. Bayar
2012-10-26
We use a recently developed formalism which generalizes the Weinberg's compositeness condition to partial waves higher than s-wave in order to determine the probability of having a $K \\pi$ component in the $K^*$ wave function. A fit is made to the $K \\pi$ phase shifts in p-wave, from where the coupling of $K^*$ to $K \\pi$ and the $K \\pi$ loop function are determined. These ingredients allow us to determine that the $K^*$ is a genuine state, different to a $K \\pi$ component, in a proportion of about 80%.
Physical measurements of breaking wave impact on a floating wave energy converter
NASA Astrophysics Data System (ADS)
Hann, Martyn R.; Greaves, Deborah M.; Raby, Alison
2013-04-01
Marine energy converter must both efficiently extract energy in small to moderate seas and also successfully survive storms and potential collisions. Extreme loads on devices are therefore an important consideration in their design process. X-MED is a SuperGen UKCMER project and is a collaboration between the Universities of Manchester, Edinburgh and Plymouth and the Scottish Association for Marine Sciences. Its objective is to extend the knowledge of extreme loads due to waves, currents, flotsam and mammal impacts. Plymouth Universities contribution to the X-MED project involves measuring the loading and response of a taut moored floating body due to steep and breaking wave impacts, in both long crested and directional sea states. These measurements are then to be reproduced in STAR-CCM+, a commercial volume of fluid CFD solver, so as to develop techniques to predict the wave loading on wave energy converters. The measurements presented here were conducted in Plymouth Universities newly opened COAST laboratories 35m long, 15.5m wide and 3m deep ocean basin. A 0.5m diameter taut moored hemispherical buoy was used to represent a floating wave energy device or support structure. The changes in the buoys 6 degree of freedom motion and mooring loads are presented due to focused breaking wave impacts, with the breaking point of the wave changed relative to the buoy.
Deep inelastic scattering and light-cone wave functions
Belyaev, V.M.; Johnson, M.B.
1996-09-01
In the framework of light-cone QCD rules, we study the valence quark distribution function {ital q}({ital x}{sub B}) of a pion for moderate {ital x}{sub B}. The sum rule with the leading twist-2 wave function gives {ital q}({ital x}{sub B}) = {phi}{sub {pi}}({ital x}{sub B}). Twist-4 wave functions give about 30% for {ital x}{sub B} {approx}0.5. It is shown that QCD sum rule predictions, with the asymptotic pion wave function, are in good agreement with experimental data. We found that a two-hump profile for the twist-2 wave function leads to a valence quark distribution function that contradicts experimental data.
Impact-induced tensile waves in a kind of phase-transforming materials
Shou-Jun Huang
2010-07-23
This paper concerns the global propagation of impact-induced tensile waves in a kind of phase-transforming materials. It is well-known that the governing system of partial differential equations is hyperbolic-elliptic and the initial-boundary value problem is not well-posed at all levels of loading. By making use of fully nonlinear stress-strain curve to model this material, Dai and Kong succeeded in constructing a physical solution of the above initial-boundary value problem. For the impact of intermediate range, they assumed that $\\beta<3\\alpha$ in the stress-response function for simplicity. In this paper, we revisit the impact problem and consider the propagation of impact-induced tensile waves for all values of the parameters $\\alpha$ and $\\beta$. The physical solutions for all levels of loading are obtained completely.
Breaking wave impact forces on truss support structures for offshore wind turbines
NASA Astrophysics Data System (ADS)
Cie?likiewicz, Witold; Gudmestad, Ove T.; Podra?ka, Olga
2014-05-01
Due to depletion of the conventional energy sources, wind energy is becoming more popular these days. Wind energy is being produced mostly from onshore farms, but there is a clear tendency to transfer wind farms to the sea. The foundations of offshore wind turbines may be truss structures and might be located in shallow water, where are subjected to highly varying hydrodynamic loads, particularly from plunging breaking waves. There are models for impact forces prediction on monopiles. Typically the total wave force on slender pile from breaking waves is a superposition of slowly varying quasi-static force, calculated from the Morison equation and additional dynamical, short duration force due to the impact of the breaker front or breaker tongue. There is not much research done on the truss structures of wind turbines and there are still uncertainties on slamming wave forces, due to plunging breaking waves on those structures. Within the WaveSlam (Wave slamming forces on truss structures in shallow water) project the large scale tests were carried out in 2013 at the Large Wave Flume in Forschungszentrum Küste (FZK) in Hannover, Germany. The following institutions participated in this initiative: the University of Stavanger and the Norwegian University of Science and Technology (project management), University of Gda?sk, Poland, Hamburg University of Technology and the University of Rostock, Germany and Reinertsen AS, Norway. This work was supported by the EU 7th Framework Programme through the grant to the budget of the Integrating Activity HYDRALAB IV. The main aim of the experiment was to investigate the wave slamming forces on truss structures, development of new and improvement of existing methods to calculate forces from the plunging breakers. The majority of the measurements were carried out for regular waves with specified frequencies and wave heights as well as for the irregular waves based on JONSWAP spectrum. The truss structure was equipped with both total and local force transducers which measured the response of the structure to the impact force. Also, the free surface elevations, the water particle velocity and the water particle acceleration were recorded during the WaveSlam experiment. Both the total and the local force data have been analysed using the Frequency Response Function method, which has been already applied to the estimation of the wave slamming forces. The results of this classical approach were compared to the calculated slamming forces based on Goda and Wienke and Oumeraci theories. Slamming wave forces and slamming coefficients calculated using both models appeared to be very much larger than those obtained from the analysed recorded data, therefore there is a need for further research. Details of this research and modelling results will be presented in the final poster.
Nonstandard jump functions for radically symmetric shock waves
Baty, Roy S; Tucker, Don H; Stanescu, Dan
2008-01-01
Nonstandard analysis is applied to derive generalized jump functions for radially symmetric, one-dimensional, magnetogasdynamic shock waves. It is assumed that the shock wave jumps occur on infinitesimal intervals and the jump functions for the physical parameters occur smoothly across these intervals. Locally integrable predistributions of the Heaviside function are used to model the flow variables across a shock wave. The equations of motion expressed in nonconservative form are then applied to derive unambiguous relationships between the jump functions for the physical parameters for two families of self-similar flows. It is shown that the microstructures for these families of radially symmetric, magnetogasdynamic shock waves coincide in a nonstandard sense for a specified density jump function.
Boundary conditions on internal three-body wave functions
Mitchell, Kevin A.; Littlejohn, Robert G.
1999-10-01
For a three-body system, a quantum wave function {Psi}{sub m}{sup {ell}} with definite {ell} and m quantum numbers may be expressed in terms of an internal wave function {chi}{sub k}{sup {ell}} which is a function of three internal coordinates. This article provides necessary and sufficient constraints on {chi}{sub k}{sup {ell}} to ensure that the external wave function {Psi}{sub k}{sup {ell}} is analytic. These constraints effectively amount to boundary conditions on {chi}{sub k}{sup {ell}} and its derivatives at the boundary of the internal space. Such conditions find similarities in the (planar) two-body problem where the wave function (to lowest order) has the form r{sup |m|} at the origin. We expect the boundary conditions to prove useful for constructing singularity free three-body basis sets for the case of nonvanishing angular momentum.
Nonstandard jump functions for radially symmetric shock waves
Baty, Roy S.; Tucker, Don H.; Stanescu, Dan
2008-10-01
Nonstandard analysis is applied to derive generalized jump functions for radially symmetric, one-dimensional, magnetogasdynamic shock waves. It is assumed that the shock wave jumps occur on infinitesimal intervals, and the jump functions for the physical parameters occur smoothly across these intervals. Locally integrable predistributions of the Heaviside function are used to model the flow variables across a shock wave. The equations of motion expressed in nonconservative form are then applied to derive unambiguous relationships between the jump functions for the physical parameters for two families of self-similar flows. It is shown that the microstructures for these families of radially symmetric, magnetogasdynamic shock waves coincide in a nonstandard sense for a specified density jump function
Real Tunneling Solutions and the Hartle-Hawking Wave Function
S. Carlip
1993-01-08
A real tunneling solution is an instanton for the Hartle-Hawking path integral with vanishing extrinsic curvature (vanishing ``momentum'') at the boundary. Since the final momentum is fixed, its conjugate cannot be specified freely; consequently, such an instanton will contribute to the wave function at only one or a few isolated spatial geometries. I show that these geometries are the extrema of the Hartle-Hawking wave function in the semiclassical approximation, and provide some evidence that with a suitable choice of time parameter, these extrema are the maxima of the wave function at a fixed time.
Dark energy from quantum wave function collapse of dark matter
A. S. Majumdar; D. Home; S. Sinha
2009-09-03
Dynamical wave function collapse models entail the continuous liberation of a specified rate of energy arising from the interaction of a fluctuating scalar field with the matter wave function. We consider the wave function collapse process for the constituents of dark matter in our universe. Beginning from a particular early era of the universe chosen from physical considerations, the rate of the associated energy liberation is integrated to yield the requisite magnitude of dark energy around the era of galaxy formation. Further, the equation of state for the liberated energy approaches $w \\to -1$ asymptotically, providing a mechanism to generate the present acceleration of the universe.
Pole wave-function renormalization prescription for unstable particles
Yong Zhou
2007-04-23
We base a new wave-function renormalization prescription on the pole mass renormalization prescription, in which the Wave-function Renormalization Constant (WRC) is extracted by expanding the particle's propagator around its pole, rather than its physical mass point as convention. We find the difference between the new and the conventional WRC is gauge-parameter dependent for unstable particles beyond one-loop level, which will lead to some physical results gauge dependent under the conventional wave-function renormalization prescription beyond one-loop level.
Investigation of the recurrence relations for the spheroidal wave functions
Guihui Tian; Shuquan Zhong
2009-12-10
The perturbation method in supersymmetric quantum mechanics (SUSYQM) is used to study the spheroidal wave functions' recurrence relations, which are revealed by the shape-invariance property of the super-potential. The super-potential is expanded by the parameter alpha and could be gotten by approximation method. Up to the first order, it has the shape-invariance property and the excited spheroidal wave functions are gotten. Also, all the first term eigenfunctions obtained are in closed form. They are advantageous to investigating for involved physical problems of spheroidal wave function.
Impact of plunging breaking waves on a partially submerged cube
NASA Astrophysics Data System (ADS)
Wang, A.; Ikeda, C.; Duncan, J. H.
2013-11-01
The impact of a deep-water plunging breaking wave on a partially submerged cube is studied experimentally in a tank that is 14.8 m long and 1.2 m wide with a water depth of 0.91 m. The breakers are created from dispersively focused wave packets generated by a programmable wave maker. The water surface profile in the vertical center plane of the cube is measured using a cinematic laser-induced fluorescence technique with movie frame rates ranging from 300 to 4,500 Hz. The pressure distribution on the front face of the cube is measured with 24 fast-response sensors simultaneously with the wave profile measurements. The cube is positioned vertically at three heights relative to the mean water level and horizontally at a distance from the wave maker where a strong vertical water jet is formed. The portion of the water surface between the contact point on the front face of the cube and the wave crest is fitted with a circular arc and the radius and vertical position of the fitted circle is tracked during the impact. The vertical acceleration of the contact point reaches more than 50 times the acceleration of gravity and the pressure distribution just below the free surface shows a localized high-pressure region with a very high vertical pressure gradient. This work is supported by the Office of Naval Research under grant N000141110095.
Covariant Wave Function Reduction and Coherent Decays of Kaon Pair
Bernd A. Berg
1998-09-12
The recently developed relativistically covariant formulation of wave function reduction is illustrated for Lipkin's proposal to study CP violation in the coherent decay of kaon pairs. Covariant results are obtained in agreement with an amplitude approach proposed in the literature.
Multi-time wave functions for quantum field theory
Petrat, Sören; Tumulka, Roderich
2014-06-15
Multi-time wave functions such as ?(t{sub 1},x{sub 1},…,t{sub N},x{sub N}) have one time variable t{sub j} for each particle. This type of wave function arises as a relativistic generalization of the wave function ?(t,x{sub 1},…,x{sub N}) of non-relativistic quantum mechanics. We show here how a quantum field theory can be formulated in terms of multi-time wave functions. We mainly consider a particular quantum field theory that features particle creation and annihilation. Starting from the particle–position representation of state vectors in Fock space, we introduce multi-time wave functions with a variable number of time variables, set up multi-time evolution equations, and show that they are consistent. Moreover, we discuss the relation of the multi-time wave function to two other representations, the Tomonaga–Schwinger representation and the Heisenberg picture in terms of operator-valued fields on space–time. In a certain sense and under natural assumptions, we find that all three representations are equivalent; yet, we point out that the multi-time formulation has several technical and conceptual advantages. -- Highlights: •Multi-time wave functions are manifestly Lorentz-covariant objects. •We develop consistent multi-time equations with interaction for quantum field theory. •We discuss in detail a particular model with particle creation and annihilation. •We show how multi-time wave functions are related to the Tomonaga–Schwinger approach. •We show that they have a simple representation in terms of operator valued fields.
Factorized molecular wave functions: Analysis of the nuclear factor.
Lefebvre, R
2015-06-01
The exact factorization of molecular wave functions leads to nuclear factors which should be nodeless functions. We reconsider the case of vibrational perturbations in a diatomic species, a situation usually treated by combining Born-Oppenheimer products. It was shown [R. Lefebvre, J. Chem. Phys. 142, 074106 (2015)] that it is possible to derive, from the solutions of coupled equations, the form of the factorized function. By increasing artificially the interstate coupling in the usual approach, the adiabatic regime can be reached, whereby the wave function can be reduced to a single product. The nuclear factor of this product is determined by the lowest of the two potentials obtained by diagonalization of the potential matrix. By comparison with the nuclear wave function of the factorized scheme, it is shown that by a simple rectification, an agreement is obtained between the modified nodeless function and that of the adiabatic scheme. PMID:26049477
The effects of extracorporeal shock wave lithotripsy on pacemaker function.
Langberg, J; Abber, J; Thuroff, J W; Griffin, J C
1987-09-01
Twenty-two pacemaker pulse generators were exposed to shock waves of an extracorporeal shock wave lithotripter to assess the effects of the extremely high pressure transients on pacemaker function. The pulse generator and distal aspect of the lead were positioned 5 cm from the focal point of the lithotripter and 10 cm from each other. Pulse generator function was analyzed during shock wave delivery synchronized with pulse generator output, during shock waves at a rate faster than the escape rate, and after exposure to lithotripsy. During shock waves delivered synchronously with pulse generator output, only one of 22 pulse generators malfunctioned by intermittently reverting to the magnet rate. When subjected to shock waves at a rate greater than the escape rate, 50% of the pulse generators were inhibited by electromechanical interference from the lithotripter. Both bipolar and unipolar devices were affected. However, analysis after exposure to shock waves showed that none of the pacemakers was damaged or spuriously reprogrammed. In conclusion, cardiac pacemakers do not appear to be damaged or reprogrammed by exposure to extracorporeal shock wave lithotripsy. The likelihood of false inhibition appears to be very low if shock waves are delivered synchronously with the QRS. PMID:2444938
Do Heat Waves have an Impact on Terrestrial Water Storage?
NASA Astrophysics Data System (ADS)
Brena-Naranjo, A.; Teuling, R.; Pedrozo-Acuña, A.
2014-12-01
Recent works have investigated the impact of heat waves on the surface energy and carbon balance. However, less attention has been given to the impacts on terrestrial hydrology. During the summer of 2010, the occurrence of an exceptional heat wave affected severely the Northern Hemisphere. The extension (more than 2 million km2) and severity of this extreme event caused substantial ecosystem damage (more than 1 million ha of forest fires), economic and human losses (~500 billion USD and more than 17 million of indirect deaths, respectively). This work investigates for the first time the impacts of the 2010 summer heat wave on terrestrial water storage. Our study area comprises three different regions where air temperature records were established or almost established during the summer: Western Russia, the Middle East and Eastern Sahel. Anomalies of terrestrial water storage derived from the Gravity Recovery and Climate Experiment (GRACE) were used to infer water storage deficits during the 2003-2013 period. Our analysis shows that Russia experienced the most severe water storage decline, followed by the Middle East, whereas Eastern Sahel was not significantly affected. The impact of the heat wave was spatially uniform in Russia but highly variable in the Middle East, with the Northern part substantially more affected than the Southern region. Lag times between maxima air temperatures and lower water storage deficits for Russia and the Middle East were approximately two and seven months, respectively. The results suggest that the response of terrestrial water storage to heat waves is stronger in energy-limited environments than in water-limited regions. Such differences in the magnitude and timing between meteorological and hydrological extremes can be explained by the propagation time between atmospheric water demand and natural or anthropogenic sources of water storage.
Uniform WKB approximation of Coulomb wave functions for arbitrary partial wave
N. Michel
2008-12-12
Coulomb wave functions are difficult to compute numerically for extremely low energies, even with direct numerical integration. Hence, it is more convenient to use asymptotic formulas in this region. It is the object of this paper to derive analytical asymptotic formulas valid for arbitrary energies and partial waves. Moreover, it is possible to extend these formulas for complex values of parameters.
Optimal Execution with Nonlinear Impact Functions
Almgren, Robert F.
Optimal Execution with Nonlinear Impact Functions and Trading-Enhanced Risk Robert F. Almgren uncertainty of the realized price is increased by demanding rapid execution; we show that optimal trajectories Robert Almgren: Nonlinear Optimal Execution 2 1 Introduction In the execution of large portfolio
Prolate Spheroidal Wave Functions In q-Fourier Analysis
Lazhar Dhaouadi
2008-04-09
The prolate spheroidal wave functions, which are a special case of the spheroidal wave functions, possess a very surprising and unique property [6]. They are an orthogonal basis of both $L^2(-1,1)$ and the Paley-Wiener space of bandlimited functions. They also satisfy a discrete orthogonality relation. No other system of classical orthogonal functions is known to possess this strange property. We prove that there are new systems possessing this property in $q$-Fourier analysis. As application we give a new sampling formula with $q^n$ as sampling points, where 0 < q < 1.
Tadahiro Suhara; Naoyuki Itagaki; József Cseh; Marek P?oszajczak
2013-05-21
We propose an improved version of Antisymmetrized Quasi-Cluster Model (AQCM) to describe a smooth transition from the $\\alpha$-cluster wave function to the $jj$-coupling shell model wave function and apply it to the ground state of $^{12}$C. The cluster-shell transition in $^{12}$C is characterized in AQCM by only two parameters: $R$ representing the distance between $\\alpha$ clusters and the center of mass, and $\\Lambda$ describing the break of $\\alpha$ clusters. The optimal AQCM wave function for the ground state of $^{12}$C is an intermediate state between the three-$\\alpha$ cluster state and the shell model state with the $p_{3/2}$ subshell closure configuration. The result is consistent with that of the Antisymmetrized Molecular Dynamics (AMD), and the optimal AQCM wave function quantitatively agrees with the AMD one, although the number of degrees of freedom in AQCM is significantly fewer.
Parametric dependence of ocean wave-radar modulation transfer functions
NASA Technical Reports Server (NTRS)
Plant, W. J.; Keller, W. C.; Cross, A.
1983-01-01
Microwave techniques at X and L band were used to determine the dependence of ocean-wave radar modulation transfer functions (MTFs) on various environmental and radar parameters during the Marine Remote Sensing experiment of 1979 (MARSEN 79). These MIF are presented, as are coherence functions between the AM and FM parts of the backscattered microwave signal. It is shown that they both depend on several of these parameters. Besides confirming many of the properties of transfer functions reported by previous authors, indications are found that MTFs decrease with increasing angle between wave propagation and antenna-look directions but are essentially independent of small changes in air-sea temperature difference. However, coherence functions are much smaller when the antennas are pointed perpendicular to long waves. It is found that X band transfer functions measured with horizontally polarized microwave radiation have larger magnitudes than those obtained by using vertical polarization.
Heat wave impacts on mortality in Shanghai, 1998 and 2003
NASA Astrophysics Data System (ADS)
Tan, Jianguo; Zheng, Youfei; Song, Guixiang; Kalkstein, Laurence S.; Kalkstein, Adam J.; Tang, Xu
2007-01-01
A variety of research has linked extreme heat to heightened levels of daily mortality and, not surprisingly, heat waves both in 1998 and in 2003 all led to elevated mortality in Shanghai, China. While the heat waves in the two years were similar in meteorological character, elevated mortality was much more pronounced during the 1998 event, but it remains unclear why the human response was so varied. In order to explain the differences in human mortality between the two years’ heat waves, and to better understand how heat impacts human health, we examine a wide range of meteorological, pollution, and social variables in Shanghai during the summers (15 June to 15 September) of 1998 and 2003. Thus, the goal of this study is to determine what was responsible for the varying human health response during the two heat events. A multivariate analysis is used to investigate the relationships between mortality and heat wave intensity, duration, and timing within the summer season, along with levels of air pollution. It was found that for heat waves in both summers, mortality was strongly associated with the duration of the heat wave. In addition, while slightly higher than average, the air pollution levels for the two heat waves were similar and cannot fully explain the observed differences in human mortality. Finally, since the meteorological conditions and pollution levels for the two heat waves were alike, we conclude that improvements in living conditions in Shanghai, such as increased use of air conditioning, larger living areas, and increased urban green space, along with higher levels of heat awareness and the implementation of a heat warning system, were responsible for the lower levels of human mortality in 2003 compared to 1998.
Joint Resummation for TMD Wave Function of Pion
NASA Astrophysics Data System (ADS)
Wang, Yu-Ming
2015-02-01
QCD corrections to transverse-momentum-dependent pion wave function develop the mixed double logarithm ln x ln(? P2/k_T^2), when the gluon emission is collinear to the energetic pion. The fist scheme-independent kT factorization formula for ?*? ? ? transition form factor is achieved by resumming all the enhanced logarithms for both pion wave function and short-distance coefficient function. High-order QCD corrections and transfer momentum ? {Q2} dependence of pion form factor are found to be distinct from those predicted by the conventional resummation approach.
The Waves Caused by the Impact of Shoemaker-Levy 9 with Jupiter
NASA Astrophysics Data System (ADS)
Chen, D. H.; Bao, G.
2003-11-01
During the period 18-24 July 1994, over20 fragments of Comet Shoemaker-Levy 9 collided with Jupiter. Images taken by the Hubble Space Telescope bring to light the dynamic responses of Jupiter's atmosphere to the impact of comet Shoemaker-Levy 9. The import points are the observed circular rings surrounding five of the impact sites and spreading outward at a constant velocity of 450 m/s. The circularity of the rings suggested that they are waves. Because the wave speed appears to be constant for impacts of varying sizes, it is inferred that the propagation velocity is independent of the explosion energy, which implies linear waves. We review the three types of impact-induced waves . We provide a review on three candidate wave types of the impact-induced waves used by current theories, i.e. inertia-gravity waves, acoustic waves and seismic waves, with emphasis on the former two types.
Delta function excitation of waves in the earth's ionosphere
NASA Technical Reports Server (NTRS)
Vidmar, R. J.; Crawford, F. W.; Harker, K. J.
1983-01-01
Excitation of the earth's ionosphere by delta function current sheets is considered, and the temporal and spatial evolution of wave packets is analyzed for a two-component collisional F2 layer. Approximations of an inverse Fourier-Laplace transform via saddle point methods provide plots of typical wave packets. These illustrate cold plasma wave theory and may be used as a diagnostic tool since it is possible to relate specific features, e.g., the frequency of a modulation envelope, to plasma parameters such as the electron cyclotron frequency. It is also possible to deduce the propagation path length and orientation of a remote radio beacon.
Zou, Jun
1995-01-01
This thesis presents a result of measurements and analyses of the wave kinematics and impact loads on a scaled ISSC-TLP column fixed in a 2-D wave tank. The objective is to find out the mechanics of impact loads varied with kinematics in both space...
Goddard III, William A.
a greatly improved method for converging generalized valence bond (GVB) self-consistent wave functions-shell HF, or a single pair GVB wave function. Here we extend this method to general wave functions GVB wave functions with up to ten pairs) and comparing with other standard methods. 1. INTRODUCTION
Quantum Monte Carlo: Direct calculation of corrections to trial wave functions and their energies
Anderson, James B.
ARTICLES Quantum Monte Carlo: Direct calculation of corrections to trial wave functions for calculating the difference between a true wave function and an analytic trial wave function 0 . The method Monte Carlo QMC method for the direct calculation of corrections to trial wave functions.13 We report
Nobel Lecture: Electronic structure of matter--wave functions and density functionals*
Wu, Zhigang
Nobel Lecture: Electronic structure of matter--wave functions and density functionals* W. Kohn-physical-chemical considerations 1257 III. Density-Functional Theory--Background 1258 IV. The Hohenberg-Kohn Formulation of Density- Functional Theory 1259 A. The density n(r) as the basic variable 1259 B. The Hohenberg-Kohn variational
Correlated continuum wave functions for three particles with Coulomb interactions
Gasaneo, G.; Colavecchia, F.D.; Garibotti, C.R.; Miraglia, J.E.; Macri, P.
1997-04-01
We present an approximate solution of the Schr{umlt o}dinger equation for the three-body Coulomb problem. We write the Hamiltonian in parabolic curvilinear coordinates and study the possible separation of the wave equation as a system of coupled partial differential equations. When two of the particles are heavier than the others, we write an approximate wave equation that incorporates some terms of the Hamiltonian that before had been considered as a perturbation. Its solution can be expressed in terms of a confluent hypergeometric function of two variables. We show that the proposed wave function includes a correlation between the motion of the light particle relative to the heavy particles and verifies the correct asymptotic behavior when all particles are far from each other. Finally, we discuss the possible uses of this function in the calculation of transition matrices and differential cross sections in ionizing collisions. {copyright} {ital 1997} {ital The American Physical Society}
Propagation of Dirac Wave Functions in Accelerated Frames of Reference
Yi-Cheng Huang; Wei-Tou Ni
2004-07-30
The first-order gravity effects of Dirac wave functions are found from the inertial effects in the accelerated frames of reference. Derivations and discussions about Lense-Thirring effect and the gyrogravitational ratio for intrinsic spin are presented. We use coordinate transformations among reference frames to study and understand the Lense-Thirring effect of a scalar particle. For a Dirac particle, the wave-function transformation operator from an inertial frame to a moving accelerated frame is obtained. From this, the Dirac wave function is solved and its change of polarization gives the gyrogravitational ratio 1 for the first-order gravitational effects. The eikonal approach to this problem is presented in the end for ready extension to investigations involving curvature terms.
Quantum Corral Wave-function Engineering
NASA Astrophysics Data System (ADS)
Correa, Alfredo; Reboredo, Fernando; Balseiro, Carlos
2005-03-01
We present a theoretical method for the design and optimization of quantum corrals[1] with specific electronic properties. Taking advantage that spins are subject to a RKKY interaction that is directly controlled by the scattering of the quantum corral, we design corral structures that reproduce spin Hamiltonians with coupling constants determined a priori[2]. We solve exactly the bi-dimensional scattering problem for each corral configuration within the s-wave approximation[3] and subsequently the geometry of the quantum corral is optimized by means of simulated annealing[4] and genetic algorithms[5]. We demonstrate the possibility of automatic design of structures with complicated target electronic properties[6]. This work was performed under the auspices of the US Department of Energy by the University of California at the LLNL under contract no W-7405-Eng-48. [1] M. F. Crommie, C. P. Lutz and D. M. Eigler, Nature 403, 512 (2000) [2] D. P. DiVincenzo et al., Nature 408, 339 (2000) [3] G. A. Fiete and E. J. Heller, Rev. Mod. Phys. 75, 933 (2003) [4] M. R. A. T. N. Metropolis et al., J. Chem. Phys. 1087 (1953) [5] E. Aarts and J. K. Lenstra, eds. Local search in combinatorial problems (Princeton University Press, 1997) [6] A. A. Correa, F. Reboredo and C. Balseiro, Phys. Rev. B (in press).
Diving-wave migration using Airy functions
Albertin, U.K.
1993-08-10
A method is described for imaging seismic reflection data selected from a data volume, comprising: preprocessing said selected seismic reflection data by application of normal moveout, dip moveout and a time-domain-to-frequency-domain transformation; determining the velocity field characteristic of said data volume; forming a velocity model for said data volume by fitting a velocity function to said velocity field, said function being characterized by a linear gradient in sloth; from the velocity model, calculating parameters for defining an Airy operator; separating normal seismic data from evanescent seismic data and saving said evanescant data in a random access memory; iterating downwardly, migrating said normal seismic data with the aid of said Airy operator; extracting said evanescent data from memory and iterating upwardly, migrating said evanescent seismic data with the aid of said Airy operator; summing the results of the downward and upward iterations; and inversely Fourier-transforming the summation.
SLE description of the nodal lines of random wave functions
E. Bogomolny; R. Dubertrand; C. Schmit
2006-09-07
The nodal lines of random wave functions are investigated. We demonstrate numerically that they are well approximated by the so-called SLE_6 curves which describe the continuum limit of the percolation cluster boundaries. This result gives an additional support to the recent conjecture that the nodal domains of random (and chaotic) wave functions in the semi classical limit are adequately described by the critical percolation theory. It is also shown that using the dipolar variant of SLE reduces significantly finite size effects.
On Spontaneous Wave Function Collapse and Quantum Field Theory
Roderich Tumulka
2005-12-15
One way of obtaining a version of quantum mechanics without observers, and thus of solving the paradoxes of quantum mechanics, is to modify the Schroedinger evolution by implementing spontaneous collapses of the wave function. An explicit model of this kind was proposed in 1986 by Ghirardi, Rimini, and Weber (GRW), involving a nonlinear, stochastic evolution of the wave function. We point out how, by focussing on the essential mathematical structure of the GRW model and a clear ontology, it can be generalized to (regularized) quantum field theories in a simple and natural way.
Evolution of wave function in a dissipative system
NASA Technical Reports Server (NTRS)
Yu, Li-Hua; Sun, Chang-Pu
1994-01-01
For a dissipative system with Ohmic friction, we obtain a simple and exact solution for the wave function of the system plus the bath. It is described by the direct product in two independent Hilbert space. One of them is described by an effective Hamiltonian, the other represents the effect of the bath, i.e., the Brownian motion, thus clarifying the structure of the wave function of the system whose energy is dissipated by its interaction with the bath. No path integral technology is needed in this treatment. The derivation of the Weisskopf-Wigner line width theory follows easily.
Canonical Transformation of a Classical Wave to Generate a Complex Wave Function
NASA Astrophysics Data System (ADS)
Chen, Robert L. W.
2001-04-01
Canonical transformation (CT) of a classical field, such as the real wave function of an elastic wave, has not been well explored. A modification of the usual form of Hamiltonian density is possible such that it will lend itself readily to CT. The procedure is as follows: (1) Write down the integral with the usual H.density as the integrand - i.e. the action. (2) Integrate by part the potential energy part of H, density.(3) Fourier transform ( or more general expansion) the wave function. (4) Square-complete the integrand of (2), making use of the orthogality of Fourier terms. Then the new integrand is the equivalent of the old as an H. density. It will have the correct properties that are expected of the probability density function ( Provided it is normalied) It can be shown that the canonical variables obtained from the CT is more proper and correct than the usual psy function appearing in the first order wave equation in quantum mechanics. The difference between the two methods becomes manifest when one deals with a nonconservative system. It therefore justifies Schroedinger's insistence on the use of a real wave function.
Pointwise Green function bounds and stability of combustion waves
NASA Astrophysics Data System (ADS)
Lyng, Gregory; Raoofi, Mohammadreza; Texier, Benjamin; Zumbrun, Kevin
Generalizing similar results for viscous shock and relaxation waves, we establish sharp pointwise Green function bounds and linearized and nonlinear stability for traveling wave solutions of an abstract viscous combustion model including both Majda's model and the full reacting compressible Navier-Stokes equations with artificial viscosity with general multi-species reaction and reaction-dependent equation of state, under the necessary conditions of strong spectral stability, i.e., stable point spectrum of the linearized operator about the wave, transversality of the profile as a connection in the traveling-wave ODE, and hyperbolic stability of the associated Chapman-Jouguet (square-wave) approximation. Notably, our results apply to combustion waves of any type: weak or strong, detonations or deflagrations, reducing the study of stability to verification of a readily numerically checkable Evans function condition. Together with spectral results of Lyng and Zumbrun, this gives immediately stability of small-amplitude strong detonations in the small heat-release (i.e., fluid-dynamical) limit, simplifying and greatly extending previous results obtained by energy methods by Liu-Ying and Tesei-Tan for Majda's model and the reactive Navier-Stokes equations, respectively.
Calculation of the nucleon structure function from the nucleon wave function
NASA Technical Reports Server (NTRS)
Hussar, Paul E.
1993-01-01
Harmonic oscillator wave functions have played an historically important role in our understanding of the structure of the nucleon, most notably by providing insight into the mass spectra of the low-lying states. High energy scattering experiments are known to give us a picture of the nucleon wave function at high-momentum transfer and in a frame in which the nucleon is traveling fast. A simple model that crosses the twin bridges of momentum scale and Lorentz frame that separate the pictures of the nucleon wave function provided by the deep inelastic scattering data and by the oscillator model is presented.
Impact of Tsunami-Generated Gravity Waves on the Ionosphere
NASA Astrophysics Data System (ADS)
Huba, J. D.; Drob, D. P.
2014-12-01
The NRL first-principles ionosphere model SAMI3 is used to study the ionospheric effects associated with tsunami-driven gravity waves. It is shown that gravity-wave induced variations in the neutral wind lead to plasma velocity variations both perpendicular and parallel to the geomagnetic field. Moreover, the electric field induced by the neutral wind perturbations can map to the conjugate hemisphere. Thus, electron density variations can be generated in both hemispheres which impact the total electron content (TEC) and 6300A airglow emission. It is found that the TEC exhibits variations +/- 0.15 TECU and the 6300A airglow emission variation is up to +/- 2.5% relative to the unperturbed background airglow. These results are consistent with observational data. Research supported by NRL Base Funds and ONR BRC program.
Impact of boat-generated waves on intertidal estuarine sediments
NASA Astrophysics Data System (ADS)
Blanpain, O.; Deloffre, J.; Lafite, R.; Gomit, G.; Calluaud, D.; David, L.
2010-12-01
Hydrodynamics in the macrotidal Seine estuary (France) are controlled by the semi-diurnal tidal regime modulated seasonally by the fluvial discharge. Wind effect on sediment transport (through wind waves and swell) is observed at the mouth of the estuary. Over the last century, authorities have put emphasis on facilitating economic exchanges by means of embankment building and increased dredging activity. These developments led to allow and secure sea vessel traffic in the Seine estuary (from its mouth to the port of Rouen, 125 km upstream) but they also resulted in a change of estuarine hydrodynamics and sediment transport features. A riversides restoration policy has been recently started by port authorities. In this context, the objective of the field-based study presented is to connect vessel characteristics (i.e. speed, draft...), boat-generated waves and their sedimentary impacts. Such information will be used by stakeholders to manage riverside. The natural intertidal site of interest is located in the fluvial freshwater part of the Seine estuary characterized by a 4.5 m maximum tidal range. The foreshore slope is gently decreasing and surface sediments are composed of fine to coarse sand with occasional mud drapes. In order to decipher boat-generated events, the sampling strategy is based on continuous ADV measurements coupled with a turbidimeter and an altimeter to study sediment dynamics. These instruments are settled in the lower part of the foreshore (i) to obtain a significant dataset (i.e. oceanic instruments are not measuring in air) on a zone statically affected by boat waves and (ii) because most of boat traffic occurs during early flood or late ebb period. Spatial variations are assessed along a cross-section through grain-size analysis of surface sediments and topography measurements using pole technique. Results enhance hydrodynamic and sedimentary impacts of boat-generated waves compared respectively to tidal and wind effects. Long-term altimeter measurements in relation with boat traffic data base demonstrate that boat-generated waves are the key hydrodynamic parameter controlling short term tidal flat evolution. Concerning hydrodynamics, two main types of boat-generated waves can be distinguished: one corresponds to barges, the other to sea vessels. The critical parameter controlling wave characteristics, bottom shear stress and thus sedimentary impacts is the distance between seabed and keel. Thus, considering their larger seabed-keel distance, barges do not significantly affect the sedimentary cover of the intertidal area. On the contrary, sea-vessels can induce rapid changes of the tidal flat texture (i.e. bed flattening, mud drapes...) and morphology: erosion and sedimentation rates in a range of 0.5 to 6 cm.min-1 have been measured. Such energetic events occur generally during the squat generated wave run-up and can affect the seabed in water depths up to 1.5 m. In the freshwater part of the Seine estuary annual sediment inputs are mostly controlled by river flow (during river flood) while medium term scale evolution is dependent on tidal range and short term sediment dynamics (i.e. bedload, resuspension) on sea-vessels waves.
Surface acoustic wave depth profiling of a functionally graded material
Goossens, Jozefien; Leclaire, Philippe; Xu Xiaodong; Glorieux, Christ; Martinez, Loic; Sola, Antonella; Siligardi, Cristina; Cannillo, Valeria; Van der Donck, Tom; Celis, Jean-Pierre
2007-09-01
The potential and limitations of Rayleigh wave spectroscopy to characterize the elastic depth profile of heterogeneous functional gradient materials are investigated by comparing simulations of the surface acoustic wave dispersion curves of different profile-spectrum pairs. This inverse problem is shown to be quite ill posed. The method is then applied to extract information on the depth structure of a glass-ceramic (alumina) functionally graded material from experimental data. The surface acoustic wave analysis suggests the presence of a uniform coating region consisting of a mixture of Al{sub 2}O{sub 3} and glass, with a sharp transition between the coating and the substrate. This is confirmed by scanning electron microscope with energy dispersive x-ray analysis.
Wave Function of the Roper from Lattice QCD
Dale S. Roberts; Waseem Kamleh; Derek B. Leinweber
2013-07-26
We apply the eigenvectors from a variational analysis in lattice QCD to successfully extract the wave function of the Roper state, and a higher mass P_11 state of the nucleon. We use the 2+1 flavour 32^3x64 PACS-CS configurations at a near physical pion mass of 156 MeV. We find that both states exhibit a structure consistent with a constituent quark model. The Roper d-quark wave function contains a single node consistent with a 2S state, and the third state wave function contains two, consistent with a 3S state. A detailed comparison with constituent quark model wave functions is carried out, obtained from a Coulomb plus ramp potential. These results validate the approach of accessing these states by constructing a variational basis composed of different levels of fermion source and sink smearing. Furthermore, significant finite volume effects are apparent for these excited states which mix with multi-particle states, driving their masses away from physical values and enabling the extraction of resonance parameters from lattice QCD simulations.
Reality of the wave function and quantum entanglement
Mani Bhaumik
2014-11-14
The intrinsic fluctuations of the underlying, immutable quantum fields that fill all space and time can support the element of reality of a wave function in quantum mechanics. The mysterious non-locality of quantum entanglement may also be understood in terms of these inherent quantum fluctuations, ever-present at the most fundamental level of the universe.
Quantum Dynamics without the Wave Function Rafael D. Sorkin
Sorkin, Rafael Dolnick
version 19 Quantum Dynamics without the Wave Function Rafael D. Sorkin Perimeter Institute, 31, more in the tradition of "quantum logic", would accommodate the contradictions by dualizing to a space of "co-events" and effectively identifying reality with an element of this dual space. Reading
Quantum Dynamics without the Wave Function # Rafael D. Sorkin
Sorkin, Rafael Dolnick
version 19 Quantum Dynamics without the Wave Function # Rafael D. Sorkin Perimeter Institute, 31, more in the tradition of ``quantum logic'', would accommodate the contradictions by dualizing# to a space of ``coÂevents'' and e#ectively identifying reality with an element of this dual space. Reading
On the ground state wave function of matrix theory
NASA Astrophysics Data System (ADS)
Lin, Ying-Hsuan; Yin, Xi
2015-11-01
We propose an explicit construction of the leading terms in the asymptotic expansion of the ground state wave function of BFSS SU( N ) matrix quantum mechanics. Our proposal is consistent with the expected factorization property in various limits of the Coulomb branch, and involves a different scaling behavior from previous suggestions. We comment on some possible physical implications.
Wave function statistics and multifractality in disordered systems
Fominov, Yakov
interference · disorder · Coulomb interaction between electrons - switched off in this talk Non-localization correction to resistivity G | i Ai|2 = |Ai|2 + i=j A i Aj generically A i Aj 0 but: time-reversed paths: Ai = drdr 2 D(r, r ) #12;Wave function statistics Fyodorov, ADM 92; . . . Review: ADM, Phys. Rep. 2000
The sign of the overlap of HFB wave functions
Luis M. Robledo
2009-01-21
The problem of how to compute accurately and efficiently the sign of the overlap between two general HFB wave functions is addressed. The results obtained can easily be extrapolated to the evaluation of the sign of the trace of a density operator exponential of one body operators.
On the Ground State Wave Function of Matrix Theory
Ying-Hsuan Lin; Xi Yin
2015-08-28
We propose an explicit construction of the leading terms in the asymptotic expansion of the ground state wave function of BFSS SU(N) matrix quantum mechanics. Our proposal is consistent with the expected factorization property in various limits of the Coulomb branch, and involves a different scaling behavior from previous suggestions. We comment on some possible physical implications.
Explicitly correlated wave function for a boron atom
Puchalski, Mariusz; Pachucki, Krzysztof
2015-01-01
We present results of high-precision calculations for a boron atom's properties using wave functions expanded in the explicitly correlated Gaussian basis. We demonstrate that the well-optimized 8192 basis functions enable a determination of energy levels, ionization potential, and fine and hyperfine splittings in atomic transitions with nearly parts per million precision. The results open a window to a spectroscopic determination of nuclear properties of boron including the charge radius of the proton halo in the $^8$B nucleus.
Topological wave functions and heat equations
Murat Gunaydin; Andrew Neitzke; Boris Pioline
2008-01-10
It is generally known that the holomorphic anomaly equations in topological string theory reflect the quantum mechanical nature of the topological string partition function. We present two new results which make this assertion more precise: (i) we give a new, purely holomorphic version of the holomorphic anomaly equations, clarifying their relation to the heat equation satisfied by the Jacobi theta series; (ii) in cases where the moduli space is a Hermitian symmetric tube domain $G/K$, we show that the general solution of the anomaly equations is a matrix element $\\IP{\\Psi | g | \\Omega}$ of the Schr\\"odinger-Weil representation of a Heisenberg extension of $G$, between an arbitrary state $\\bra{\\Psi}$ and a particular vacuum state $\\ket{\\Omega}$. Based on these results, we speculate on the existence of a one-parameter generalization of the usual topological amplitude, which in symmetric cases transforms in the smallest unitary representation of the duality group $G'$ in three dimensions, and on its relations to hypermultiplet couplings, nonabelian Donaldson-Thomas theory and black hole degeneracies.
Sensory Function: Insights From Wave 2 of the National Social Life, Health, and Aging Project
Kern, David W.; Wroblewski, Kristen E.; Chen, Rachel C.; Schumm, L. Philip; McClintock, Martha K.
2014-01-01
Objectives. Sensory function, a critical component of quality of life, generally declines with age and influences health, physical activity, and social function. Sensory measures collected in Wave 2 of the National Social Life, Health, and Aging Project (NSHAP) survey focused on the personal impact of sensory function in the home environment and included: subjective assessment of vision, hearing, and touch, information on relevant home conditions and social sequelae as well as an improved objective assessment of odor detection. Method. Summary data were generated for each sensory category, stratified by age (62–90 years of age) and gender, with a focus on function in the home setting and the social consequences of sensory decrements in each modality. Results. Among both men and women, older age was associated with self-reported impairment of vision, hearing, and pleasantness of light touch. Compared with women, men reported significantly worse hearing and found light touch less appealing. There were no gender differences for vision. Overall, hearing loss seemed to have a greater impact on social function than did visual impairment. Discussion. Sensory function declines across age groups, with notable gender differences for hearing and light touch. Further analysis of sensory measures from NSHAP Wave 2 may provide important information on how sensory declines are related to health, social function, quality of life, morbidity, and mortality in this nationally representative sample of older adults. PMID:25360015
Refined applications of the collapse of the wave function
NASA Astrophysics Data System (ADS)
Stodolsky, L.
2015-05-01
In a two-part system, the collapse of the wave function of one part can put the other part in a state which would be difficult or impossible to achieve otherwise, in particular, one sensitive to small effects in the "collapse" interaction. We present some applications to the very symmetric and experimentally accessible situations of the decays ? (1020 )?KoKo , ? (3770 )?DoDo, or ? (4 s )?BoBo , involving the internal state of the two-state Ko, Do, or Bo mesons. The collapse of the wave function occasioned by a decay of one member of the pair (away side) fixes the state vector of that side's two-state system. Bose-Einstein statistics then determines the state of the recoiling meson (near side), whose evolution can then be followed further. In particular, the statistics requirement dictates that the "away side" and "near side" internal wave functions must be orthogonal at the time of the collapse. Thus a C P violation in the away side decay implies a complementary C P impurity on the near side, which can be detected in the further evolution. The C P violation so manifested is necessarily direct C P violation, since neither the mass matrix nor time evolution was involved in the collapse. A parametrization of the direct C P violation is given, and various manifestations are presented. Certain rates or combination of rates are identified which are nonzero only if there is direct C P violation. The very explicit and detailed use made of the collapse of the wave function makes the procedure interesting with respect to the fundamentals of quantum mechanics. We note an experimental consistency test for our treatment of the collapse of the wave function, which can be carried out by a certain measurement of partial decay rates.
Simulation of wind wave growth with reference source functions
NASA Astrophysics Data System (ADS)
Badulin, Sergei I.; Zakharov, Vladimir E.; Pushkarev, Andrei N.
2013-04-01
We present results of extensive simulations of wind wave growth with the so-called reference source function in the right-hand side of the Hasselmann equation written as follows First, we use Webb's algorithm [8] for calculating the exact nonlinear transfer function Snl. Second, we consider a family of wind input functions in accordance with recent consideration [9] ( )s S = ?(k)N , ?(k) = ? ? ?- f (?). in k 0 ?0 in (2) Function fin(?) describes dependence on angle ?. Parameters in (2) are tunable and determine magnitude (parameters ?0, ?0) and wave growth rate s [9]. Exponent s plays a key role in this study being responsible for reference scenarios of wave growth: s = 4-3 gives linear growth of wave momentum, s = 2 - linear growth of wave energy and s = 8-3 - constant rate of wave action growth. Note, the values are close to ones of conventional parameterizations of wave growth rates (e.g. s = 1 for [7] and s = 2 for [5]). Dissipation function Sdiss is chosen as one providing the Phillips spectrum E(?) ~ ?5 at high frequency range [3] (parameter ?diss fixes a dissipation scale of wind waves) Sdiss = Cdiss?4w?N (k)?(? - ?diss) (3) Here frequency-dependent wave steepness ?2w = E(?,?)?5-g2 makes this function to be heavily nonlinear and provides a remarkable property of stationary solutions at high frequencies: the dissipation coefficient Cdiss should keep certain value to provide the observed power-law tails close to the Phillips spectrum E(?) ~ ?-5. Our recent estimates [3] give Cdiss ? 2.0. The Hasselmann equation (1) with the new functions Sin, Sdiss (2,3) has a family of self-similar solutions of the same form as previously studied models [1,3,9] and proposes a solid basis for further theoretical and numerical study of wave evolution under action of all the physical mechanisms: wind input, wave dissipation and nonlinear transfer. Simulations of duration- and fetch-limited wind wave growth have been carried out within the above model setup to check its conformity with theoretical predictions, previous simulations [2,6,9], experimental parameterizations of wave spectra [1,4] and to specify tunable parameters of terms (2,3). These simulations showed realistic spatio-temporal scales of wave evolution and spectral shaping close to conventional parameterizations [e.g. 4]. An additional important feature of the numerical solutions is a saturation of frequency-dependent wave steepness ?w in short-frequency range. The work was supported by the Russian government contract No.11.934.31.0035, Russian Foundation for Basic Research grant 11-05-01114-a and ONR grant N00014-10-1-0991. References [1] S. I. Badulin, A. V. Babanin, D. Resio, and V. Zakharov. Weakly turbulent laws of wind-wave growth. J. Fluid Mech., 591:339-378, 2007. [2] S. I. Badulin, A. N. Pushkarev, D. Resio, and V. E. Zakharov. Self-similarity of wind-driven seas. Nonl. Proc. Geophys., 12:891-946, 2005. [3] S. I. Badulin and V. E. Zakharov. New dissipation function for weakly turbulent wind-driven seas. ArXiv e-prints, (1212.0963), December 2012. [4] M. A. Donelan, J. Hamilton, and W. H. Hui. Directional spectra of wind-generated waves. Phil. Trans. Roy. Soc. Lond. A, 315:509-562, 1985. [5] M. A. Donelan and W. J. Pierson-jr. Radar scattering and equilibrium ranges in wind-generated waves with application to scatterometry. J. Geophys. Res., 92(C5):4971-5029, 1987. [6] E. Gagnaire-Renou, M. Benoit, and S. I. Badulin. On weakly turbulent scaling of wind sea in simulations of fetch-limited growth. J. Fluid Mech., 669:178-213, 2011. [7] R. L. Snyder, F. W. Dobson, J. A. Elliot, and R. B. Long. Array measurements of atmospheric pressure fluctuations above surface gravity waves. J. Fluid Mech., 102:1-59, 1981. [8] D. J. Webb. Non-linear transfers between sea waves. Deep Sea Res., 25:279-298, 1978. [9] V. E. Zakharov, D. Resio, and A. N. Pushkarev. New wind input term consistent with experimental, theoretical and numerical considerations. ArXiv e-prints, (1212.1069), December 2012.
Yasutaka Taniguchi; Yoshiko Kanada-En'yo
2012-06-11
A method to separate a Slater determinant wave function with a two-center neck structure into spatially localized subsystems is proposed, and its potential applications are presented. An orthonormal set of spatially localized single-particle wave functions is obtained by diagonalizing the coordinate operator for the major axis of a necked system. Using the localized single-particle wave functions, the wave function of each subsystem is defined. Therefore, defined subsystem wave functions are used to obtain density distributions, mass centers, and energies of subsystems. The present method is applied to separations of Margenau--Brink cluster wave functions of $\\alpha + \\alpha$, $^{16}$O + $^{16}$O, and $\\alpha + ^{16}$O into their subsystems, and also to separations of antisymmetrized molecular dynamics wave functions of $^{10}$Be into $\\alpha$ + $^6$He subsystems. The method is simple and applicable to the separation of general Slater determinant wave functions that have neck structures into subsystem wave functions.
Helicon Wave Physics Impacts on Electrodeless Thruster Design
NASA Technical Reports Server (NTRS)
Gilland, James
2003-01-01
Effective generation of helicon waves for high density plasma sources is determined by the dispersion relation and plasma power balance. Helicon wave plasma sources inherently require an applied magnetic field of .01-0.1 T, an antenna properly designed to couple to the helicon wave in the plasma, and an rf power source in the 10-100 s of MHz, depending on propellant choice. For a plasma thruster, particularly one with a high specific impulse (>2000 s), the physics of the discharge would also have to address the use of electron cyclotron resonance (ECR) heating and magnetic expansion. In all cases the system design includes an optimized magnetic field coil, plasma source chamber, and antenna. A preliminary analysis of such a system, calling on experimental data where applicable and calculations where required, has been initiated at Glenn Research Center. Analysis results showing the mass scaling of various components as well as thruster performance projections and their impact on thruster size are discussed.
Helicon Wave Physics Impacts on Electrodeless Thruster Design
NASA Technical Reports Server (NTRS)
Gilland, James H.
2007-01-01
Effective generation of helicon waves for high density plasma sources is determined by the dispersion relation and plasma power balance. Helicon wave plasma sources inherently require an applied magnetic field of .01-0.1 T, an antenna properly designed to couple to the helicon wave in the plasma, and an rf power source in the 10-100 s of MHz, depending on propellant choice. For a plasma thruster, particularly one with a high specific impulse (>2000 s), the physics of the discharge would also have to address the use of electron cyclotron resonance (ECR) heating and magnetic expansion. In all cases the system design includes an optimized magnetic field coil, plasma source chamber, and antenna. A preliminary analysis of such a system, calling on experimental data where applicable and calculations where required, has been initiated at Glenn Research Center. Analysis results showing the mass scaling of various components as well as thruster performance projections and their impact on thruster size are discussed.
Joint resummation for pion wave function and pion transition form factor
Hsiang-nan Li; Yue-Long Shen; Yu-Ming Wang
2013-10-27
We construct an evolution equation for the pion wave function in the $k_T$ factorization theorem, whose solution sums the mixed logarithm $\\ln x\\ln k_T$ to all orders, with $x$ ($k_T$) being a parton momentum fraction (transverse momentum). This joint resummation induces strong suppression of the pion wave function in the small $x$ and large $b$ regions, $b$ being the impact parameter conjugate to $k_T$, and improves the applicability of perturbative QCD to hard exclusive processes. The above effect is similar to those from the conventional threshold resummation for the double logarithm $\\ln^2 x$ and the conventional $k_T$ resummation for $\\ln^2 k_T$. Combining the evolution equation for the hard kernel, we are able to organize all large logarithms in the $\\gamma^{\\ast} \\pi^{0} \\to \\gamma$ scattering, and to establish a scheme-independent $k_T$ factorization formula. It will be shown that the significance of next-to-leading-order contributions and saturation behaviors of this process at high energy differ from those under the conventional resummations. It implies that QCD logarithmic corrections to a process must be handled appropriately, before its data are used to extract a hadron wave function. Our predictions for the involved pion transition form factor, derived under the joint resummation and the input of a non-asymptotic pion wave function with the second Gegenbauer moment $a_2=0.05$, match reasonably well the CLEO, BaBar, and Belle data.
Response functions of free mass gravitational wave antennas
NASA Technical Reports Server (NTRS)
Estabrook, F. B.
1985-01-01
The work of Gursel, Linsay, Spero, Saulson, Whitcomb and Weiss (1984) on the response of a free-mass interferometric antenna is extended. Starting from first principles, the earlier work derived the response of a 2-arm gravitational wave antenna to plane polarized gravitational waves. Equivalent formulas (generalized slightly to allow for arbitrary elliptical polarization) are obtained by a simple differencing of the '3-pulse' Doppler response functions of two 1-arm antennas. A '4-pulse' response function is found, with quite complicated angular dependences for arbitrary incident polarization. The differencing method can as readily be used to write exact response functions ('3n+1 pulse') for antennas having multiple passes or more arms.
NASA Astrophysics Data System (ADS)
Hedayatrasa, Saeid; Bui, Tinh Quoc; Zhang, Chuanzeng; Lim, Chee Wah
2014-02-01
Numerical modeling of the Lamb wave propagation in functionally graded materials (FGMs) by a two-dimensional time-domain spectral finite element method (SpFEM) is presented. The high-order Chebyshev polynomials as approximation functions are used in the present formulation, which provides the capability to take into account the through thickness variation of the material properties. The efficiency and accuracy of the present model with one and two layers of 5th order spectral elements in modeling wave propagation in FGM plates are analyzed. Different excitation frequencies in a wide range of 28-350 kHz are investigated, and the dispersion properties obtained by the present model are verified by reference results. The through thickness wave structure of two principal Lamb modes are extracted and analyzed by the symmetry and relative amplitude of the vertical and horizontal oscillations. The differences with respect to Lamb modes generated in homogeneous plates are explained. Zero-crossing and wavelet signal processing-spectrum decomposition procedures are implemented to obtain phase and group velocities and their dispersion properties. So it is attested how this approach can be practically employed for simulation, calibration and optimization of Lamb wave based nondestructive evaluation techniques for the FGMs. The capability of modeling stress wave propagation through the thickness of an FGM specimen subjected to impact load is also investigated, which shows that the present method is highly accurate as compared with other existing reference data.
Impact! Chandra Images a Young Supernova Blast Wave
NASA Astrophysics Data System (ADS)
2000-05-01
Two images made by NASA's Chandra X-ray Observatory, one in October 1999, the other in January 2000, show for the first time the full impact of the actual blast wave from Supernova 1987A (SN1987A). The observations are the first time that X-rays from a shock wave have been imaged at such an early stage of a supernova explosion. Recent observations of SN 1987A with the Hubble Space Telescope revealed gradually brightening hot spots from a ring of matter ejected by the star thousands of years before it exploded. Chandra's X-ray images show the cause for this brightening ring. A shock wave is smashing into portions of the ring at a speed of 10 million miles per hour (4,500 kilometers per second). The gas behind the shock wave has a temperature of about ten million degrees Celsius, and is visible only with an X-ray telescope. "With Hubble we heard the whistle from the oncoming train," said David Burrows of Pennsylvania State University, University Park, the leader of the team of scientists involved in analyzing the Chandra data on SN 1987A. "Now, with Chandra, we can see the train." The X-ray observations appear to confirm the general outlines of a model developed by team member Richard McCray of the University of Colorado, Boulder, and others, which holds that a shock wave has been moving out ahead of the debris expelled by the explosion. As this shock wave collides with material outside the ring, it heats it to millions of degrees. "We are witnessing the birth of a supernova remnant for the first time," McCray said. The Chandra images clearly show the previously unseen, shock-heated matter just inside the optical ring. Comparison with observations made with Chandra in October and January, and with Hubble in February 2000, show that the X-ray emission peaks close to the newly discovered optical hot spots, and indicate that the wave is beginning to hit the ring. In the next few years, the shock wave will light up still more material in the ring, and an inward moving, or reverse, shock wave will heat the material ejected in the explosion itself. "The supernova is digging up its own past," said McCray. The observations were made on October 6, 1999, using the Advanced CCD Imaging Spectrometer (ACIS) and the High Energy Transmission Grating, and again on January 17, 2000, using ACIS. Other members of the team were Eli Michael of the University of Colorado; Dr. Una Hwang, Dr. Steven Holt and Dr. Rob Petre of NASA's Goddard Space Flight Center in Greenbelt, MD; Professor Roger Chevalier of the University of Virginia, Charlottesville; and Professors Gordon Garmire and John Nousek of Pennsylvania State University. The results will be published in an upcoming issue of the Astrophysical Journal. The ACIS instrument was built for NASA by the Massachusetts Institute of Technology, Cambridge, and Pennsylvania State University. The High Energy Transmission Grating was built by the Massachusetts Institute of Technology. NASA's Marshall Space Flight Center in Huntsville, AL, manages the Chandra program. TRW, Inc., Redondo Beach, CA, is the prime contractor for the spacecraft. The Smithsonian's Chandra X-ray Center controls science and flight operations from Cambridge, MA. More About SN 1987A Images to illustrate this release and more information on Chandra's progress can be found on the Internet at: http://chandra.harvard.edu/photo/2000/sn1987a/index.html AND http://chandra.nasa.gov More About SN 1987A
Boundary conditions on internal three-body wave functions Kevin A. Mitchell and Robert G. Littlejohn
Mitchell, Kevin A.
Boundary conditions on internal three-body wave functions Kevin A. Mitchell and Robert G and m quantum numbers may be expressed in terms of an internal wave function k l , which is a function and where k l , the ``internal wave func- tion,'' is a function of three internal or shape coordinates
Acoustic Kappa-Density Fluctuation Waves in Suprathermal Kappa Function Fluids
Michael R. Collier; Aaron Roberts; Adolfo Vinas
2007-10-20
We describe a new wave mode similar to the acoustic wave in which both density and velocity fluctuate. Unlike the acoustic wave in which the underlying distribution is Maxwellian, this new wave mode occurs when the underlying distribution is a suprathermal kappa function and involves fluctuations in the power law index, kappa. This wave mode always propagates faster than the acoustic wave with an equivalent effective temperature and becomes the acoustic wave in the Maxwellian limit as kappa goes to infinity.
Phases of Augmented Hadronic Light-Front Wave Functions
Brodsky, Stanley J.; Pasquini, Barbara; Xiao, Bo-Wen; Yuan, Feng; /LBNL, NSD /RIKEN BNL
2010-02-15
It is an important question whether the final/initial state gluonic interactions which lead to naive-time-reversal-odd single-spin asymmetries and diffraction at leading twist can be associated in a definite way with the light-front wave function hadronic eigensolutions of QCD. We use light-front time-ordered perturbation theory to obtain augmented light-front wave functions which contain an imaginary phase which depends on the choice of advanced or retarded boundary condition for the gauge potential in light-cone gauge. We apply this formalism to the wave functions of the valence Fock states of nucleons and pions, and show how this illuminates the factorization properties of naive-time-reversal-odd transverse momentum dependent observables which arise from rescattering. In particular, one calculates the identical leading-twist Sivers function from the overlap of augmented light-front wavefunctions that one obtains from explicit calculations of the single-spin asymmetry in semi-inclusive deep inelastic lepton-polarized nucleon scattering where the required phases come from the final-state rescattering of the struck quark with the nucleon spectators.
Phases of Augmented Hadronic Light-Front Wave Functions
Yuan, Feng; Brodsky, S.J.; Pasquini, B.; Xiao, B.-W.
2010-01-05
It is an important question whether the final/initial state gluonic interactions which lead to naive-time-reversal-odd single-spin asymmetries and diffraction at leading twist can be associated in a definite way with the light-front wave function hadronic eigensolutions of QCD. We use light-front time-ordered perturbation theory to obtain augmented light-front wave functions which contain an imaginary phase which depends on the choice of advanced or retarded boundary condition for the gauge potential in light-cone gauge. We apply this formalism to the wave functions of the valence Fock states of nucleons and pions, and show how this illuminates the factorization properties of naive-time-reversal-odd transverse momentum dependent observables which arise from rescattering. In particular, one calculates the identical leading-twist Sivers function from the overlap of augmented light-front wavefunctions that one obtains from explicit calculations of the single-spin asymmetry in semi-inclusive deep inelastic lepton-polarized nucleon scattering where the required phases come from the final-state rescattering of the struck quark with the nucleon spectators.
Deducing spectroscopic factors from wave-function asymptotics
Capel, P.; Danielewicz, P.; Nunes, F. M.
2010-11-15
In a coupled-channel model, we explore the effects of coupling between configurations on the radial behavior of the wave function and, in particular, on the spectroscopic factor (SF) and the asymptotic normalization coefficient (ANC). We evaluate the extraction of a SF from the ratio of the ANC of the coupled-channel model to that of a single-particle approximation of the wave function. We perform this study within a core+n collective model, which includes two states of the core that connect by a rotational coupling. To get additional insights, we also use a simplified model that takes a {delta} function for the coupling potential. Calculations are performed for {sup 11}Be. Fair agreement is obtained between the SF inferred from the single-particle approximation and the one obtained within the coupled-channel models. Significant discrepancies are observed only for large coupling strength and/or large admixture, that is, a small SF. This suggests that reliable SFs can be deduced from the wave-function asymptotics when the structure is dominated by one configuration, that is, for a large SF.
Phases of Augmented Hadronic Light-Front Wave Functions
Stanley J. Brodsky; Barbara Pasquini; Bowen Xiao; Feng Yuan
2010-01-08
It is an important question whether the final/initial state gluonic interactions which lead to naive-time-reversal-odd single-spin asymmetries and diffraction at leading twist can be associated in a definite way with the light-front wave function hadronic eigensolutions of QCD. We use light-front time-ordered perturbation theory to obtain augmented light-front wave functions which contain an imaginary phase which depends on the choice of advanced or retarded boundary condition for the gauge potential in light-cone gauge. We apply this formalism to the wave functions of the valence Fock states of nucleons and pions, and show how this illuminates the factorization properties of naive-time-reversal-odd transverse momentum dependent observables which arise from rescattering. In particular, one calculates the identical leading-twist Sivers function from the overlap of augmented light-front wavefunctions that one obtains from explicit calculations of the single-spin asymmetry in semi-inclusive deep inelastic lepton-polarized nucleon scattering where the required phases come from the final-state rescattering of the struck quark with the nucleon spectators.
Deducing spectroscopic factors from wave-function asymptotics
P. Capel; P. Danielewicz; F. M. Nunes
2010-12-08
In a coupled-channel model, we explore the effects of coupling between configurations on the radial behavior of the wave function and, in particular, on the spectroscopic factor (SF) and the asymptotic normalization coefficient (ANC). We evaluate the extraction of a SF from the ratio of the ANC of the coupled-channel model to that of a single-particle approximation of the wave function. We perform this study within a core + n collective model, which includes two states of the core that connect by a rotational coupling. To get additional insights, we also use a simplified model that takes a delta function for the coupling potential. Calculations are performed for 11Be. Fair agreement is obtained between the SF inferred from the single-particle approximation and the one obtained within the coupled-channel models. Significant discrepancies are observed only for large coupling strength and/or large admixture, that is, a small SF. This suggests that reliable SFs can be deduced from the wave-function asymptotics when the structure is dominated by one configuration, that is, for a large SF.
NASA Technical Reports Server (NTRS)
Huang, K.-N.
1977-01-01
A computational procedure for calculating correlated wave functions is proposed for three-particle systems interacting through Coulomb forces. Calculations are carried out for the muonic helium atom. Variational wave functions which explicitly contain interparticle coordinates are presented for the ground and excited states. General Hylleraas-type trial functions are used as the basis for the correlated wave functions. Excited-state energies of the muonic helium atom computed from 1- and 35-term wave functions are listed for four states.
The waves caused by the impact of Shoemaker-Levy 9 on jupiter
NASA Astrophysics Data System (ADS)
Chen, Dao-han; Bao, Gang
During the period 18-24 July 1994, over 20 fragments of Comet Shoemaker-Levy 9 collided with Jupiter. Images taken by the Hubble Space Telescope bring to light the dynamic responses of Jupiter's atmosphere to the impact. Of consequence are the observed circular rings surrounding five of the impact sites and spreading outward at a constant velocity of 450 m/s. The circularity of the rings suggested that they are waves. Because the wave speed appears to be constant for impacts of varying sizes, it is inferred that the propagation velocity is independent of the explosion energy, which implies linear waves. We review the three types of impact-induced waves used in current theories, namely, inertia-gravity waves, acoustic waves and seismic waves, with emphasis on the first two.
Measurement and Shaping of Biphoton Spectral Wave Functions
NASA Astrophysics Data System (ADS)
Tischler, N.; Büse, A.; Helt, L. G.; Juan, M. L.; Piro, N.; Ghosh, J.; Steel, M. J.; Molina-Terriza, G.
2015-11-01
In this work we present a simple method to reconstruct the complex spectral wave function of a biphoton, and hence gain complete information about the spectral and temporal properties of a photon pair. The technique, which relies on quantum interference, is applicable to biphoton states produced with a monochromatic pump when a shift of the pump frequency produces a shift in the relative frequencies contributing to the biphoton. We demonstrate an example of such a situation in type-II parametric down conversion allowing arbitrary paraxial spatial pump and detection modes. Moreover, our test cases demonstrate the possibility to shape the spectral wave function. This is achieved by choosing the spatial mode of the pump and of the detection modes, and takes advantage of spatiotemporal correlations.
Electron number probability distributions for correlated wave functions.
Francisco, E; Martín Pendás, A; Blanco, M A
2007-03-01
Efficient formulas for computing the probability of finding exactly an integer number of electrons in an arbitrarily chosen volume are only known for single-determinant wave functions [E. Cances et al., Theor. Chem. Acc. 111, 373 (2004)]. In this article, an algebraic method is presented that extends these formulas to the case of multideterminant wave functions and any number of disjoint volumes. The derived expressions are applied to compute the probabilities within the atomic domains derived from the space partitioning based on the quantum theory of atoms in molecules. Results for a series of test molecules are presented, paying particular attention to the effects of electron correlation and of some numerical approximations on the computed probabilities. PMID:17362099
Measurement and Shaping of Biphoton Spectral Wave Functions.
Tischler, N; Büse, A; Helt, L G; Juan, M L; Piro, N; Ghosh, J; Steel, M J; Molina-Terriza, G
2015-11-01
In this work we present a simple method to reconstruct the complex spectral wave function of a biphoton, and hence gain complete information about the spectral and temporal properties of a photon pair. The technique, which relies on quantum interference, is applicable to biphoton states produced with a monochromatic pump when a shift of the pump frequency produces a shift in the relative frequencies contributing to the biphoton. We demonstrate an example of such a situation in type-II parametric down conversion allowing arbitrary paraxial spatial pump and detection modes. Moreover, our test cases demonstrate the possibility to shape the spectral wave function. This is achieved by choosing the spatial mode of the pump and of the detection modes, and takes advantage of spatiotemporal correlations. PMID:26588380
Coevolution of Quantum Wave Functions and the Friedmann Universe
W. Q. Sumner; D. Y. Sumner
2007-04-20
Erwin Schrodinger (1939) proved that quantum wave functions coevolve with the curved spacetime of the Friedmann universe. Schrodinger's derivation explains the Hubble redshift of photons in an expanding universe, the energy changes of moving particles, and establishes the coevolution of atoms and other quantum systems with spacetime geometry. The assumption often made that small quantum systems are isolated and that their properties remain constant as the Friedmann universe evolves is incompatible with relativistic quantum mechanics and with general relativity.
Detecting topological order in a ground state wave function.
Levin, Michael; Wen, Xiao-Gang
2006-03-24
A large class of topological orders can be understood and classified using the string-net condensation picture. These topological orders can be characterized by a set of data (N, di, F(lmn)(ijk), delta(ijk). We describe a way to detect this kind of topological order using only the ground state wave function. The method involves computing a quantity called the "topological entropy" which directly measures the total quantum dimension D= Sum(id2i). PMID:16605803
Detecting Topological Order in a Ground State Wave Function
NASA Astrophysics Data System (ADS)
Levin, Michael; Wen, Xiao-Gang
2006-03-01
A large class of topological orders can be understood and classified using the string-net condensation picture. These topological orders can be characterized by a set of data (N,di,Flmnijk,?ijk). We describe a way to detect this kind of topological order using only the ground state wave function. The method involves computing a quantity called the “topological entropy” which directly measures the total quantum dimension D=?idi2.
Interaction between light and matter: A photon wave function approach
Pablo L. Saldanha; C. H. Monken
2011-06-14
The Bialynicki-Birula-Sipe photon wave function formalism is extended to include the interaction between photons and continuous non-absorptive media. When the second quantization of this formalism is introduced, a new way of describing the quantum interactions between light and matter emerges. As an example of application, the quantum state of the twin photons generated by parametric down conversion is obtained in agreement with previous treatments, but with a more intuitive interpretation.
Wave Function of the Roper from Lattice QCD
Roberts, Dale S; Leinweber, Derek B
2013-01-01
We apply the eigenvectors from a variational analysis in lattice QCD to successfully extract the wave function of the Roper state, and the next P_11 state of the nucleon, associated with the N*(1710). We use the 2+1 flavour 32^3x64 PACS-CS configurations at a near physical pion mass of 156 MeV. We find that both states exhibit a structure consistent with a constituent quark model. The Roper d-quark wave function contains a single node consistent with a 2S state, and the N*(1710) contains two, consistent with a 3S state. A detailed comparison with constituent quark model wave functions is carried out, obtained from a Coulomb + ramp potential. These results validate the approach of accessing these states by constructing a variational basis composed of different levels of fermion source and sink smearing. Furthermore, significant finite volume effects are apparent for these excited states which mix with multi-particle states, driving their masses away from physical values and enabling the extraction of resonance...
Resummation of rapidity logarithms in $B$ meson wave functions
Hsiang-nan Li; Yue-Long Shen; Yu-Ming Wang
2013-01-03
We construct an evolution equation for the $B$ meson wave functions in the $k_T$ factorization theorem, whose solutions sum the double logarithms associated with the light-cone singularities, namely, the rapidity logarithms. The derivation is subtler than that of the Sudakov resummation for an energetic light hadron, due to the involvement of the effective heavy-quark field. The renormalization-group evolution in the factorization scale needs to be included in order to derive an ultraviolet-finite and scale-invariant kernel for resumming the rapidity logarithms. It is observed that this kernel is similar to that of the joint resummation for QCD processes in extreme kinematic regions, which combines the threshold and $k_T$ resummations. We show that the resummation effect maintains the normalization of the $B$ meson wave functions, and strengths their convergent behavior at small spectator momentum. The resummation improved $B$ meson wave functions are then employed in the leading-order analysis of the $B\\to\\pi$ transition form factors, which lead to approximately 25% deduction in the large recoil region.
Measurement of the Pion and Photon Light-Cone Wave Functions by Diffractive Dissociation
Daniel Ashery
2005-11-24
The measurement of the pion light-cone wave function is revisited and results for the Gegenbauer coefficients are presented. Mesurements of the photon electromagnetic and hadronic wave functions are described and results are presented.
Zhu, Hong-Ming; Chen, Jin-Wang; Pan, Xiao-Yin; Sahni, Viraht
2014-01-14
We derive via the interaction “representation” the many-body wave function for harmonically confined electrons in the presence of a magnetostatic field and perturbed by a spatially homogeneous time-dependent electric field—the Generalized Kohn Theorem (GKT) wave function. In the absence of the harmonic confinement – the uniform electron gas – the GKT wave function reduces to the Kohn Theorem wave function. Without the magnetostatic field, the GKT wave function is the Harmonic Potential Theorem wave function. We further prove the validity of the connection between the GKT wave function derived and the system in an accelerated frame of reference. Finally, we provide examples of the application of the GKT wave function.
Statistical properties and correlation functions for drift waves
NASA Technical Reports Server (NTRS)
Horton, W.
1986-01-01
The dissipative one-field drift wave equation is solved using the pseudospectral method to generate steady-state fluctuations. The fluctuations are analyzed in terms of space-time correlation functions and modal probability distributions. Nearly Gaussian statistics and exponential decay of the two-time correlation functions occur in the presence of electron dissipation, while in the absence of electron dissipation long-lived vortical structures occur. Formulas from renormalized, Markovianized statistical turbulence theory are given in a local approximation to interpret the dissipative turbulence.
Computational aspects of the continuum quaternionic wave functions for hydrogen
Morais, J.
2014-10-15
Over the past few years considerable attention has been given to the role played by the Hydrogen Continuum Wave Functions (HCWFs) in quantum theory. The HCWFs arise via the method of separation of variables for the time-independent Schrödinger equation in spherical coordinates. The HCWFs are composed of products of a radial part involving associated Laguerre polynomials multiplied by exponential factors and an angular part that is the spherical harmonics. In the present paper we introduce the continuum wave functions for hydrogen within quaternionic analysis ((R)QHCWFs), a result which is not available in the existing literature. In particular, the underlying functions are of three real variables and take on either values in the reduced and full quaternions (identified, respectively, with R{sup 3} and R{sup 4}). We prove that the (R)QHCWFs are orthonormal to one another. The representation of these functions in terms of the HCWFs are explicitly given, from which several recurrence formulae for fast computer implementations can be derived. A summary of fundamental properties and further computation of the hydrogen-like atom transforms of the (R)QHCWFs are also discussed. We address all the above and explore some basic facts of the arising quaternionic function theory. As an application, we provide the reader with plot simulations that demonstrate the effectiveness of our approach. (R)QHCWFs are new in the literature and have some consequences that are now under investigation.
NASA Astrophysics Data System (ADS)
Khan, Shehryar; Kubica-Misztal, Aleksandra; Kruk, Danuta; Kowalewski, Jozef; Odelius, Michael
2015-01-01
The zero-field splitting (ZFS) of the electronic ground state in paramagnetic ions is a sensitive probe of the variations in the electronic and molecular structure with an impact on fields ranging from fundamental physical chemistry to medical applications. A detailed analysis of the ZFS in a series of symmetric Gd(III) complexes is presented in order to establish the applicability and accuracy of computational methods using multiconfigurational complete-active-space self-consistent field wave functions and of density functional theory calculations. The various computational schemes are then applied to larger complexes Gd(III)DOTA(H2O)-, Gd(III)DTPA(H2O)2-, and Gd(III)(H2O)83+ in order to analyze how the theoretical results compare to experimentally derived parameters. In contrast to approximations based on density functional theory, the multiconfigurational methods produce results for the ZFS of Gd(III) complexes on the correct order of magnitude.
Projections of heat waves with high impact on human health in Europe A. Amengual a,
Romero, Romu
Projections of heat waves with high impact on human health in Europe A. Amengual a, , V. Homar: Climate change Heat waves Human health Physiologically equivalent temperature Regional climate modeling lasting heat waves. The most hazardous conditions emerge when extreme daytime temperatures combine
A critical survey of wave propagation and impact in composite materials
NASA Technical Reports Server (NTRS)
Moon, F. C.
1973-01-01
A review of the field of stress waves in composite materials is presented covering the period up to December 1972. The major properties of waves in composites are discussed and a summary is made of the major experimental results in this field. Various theoretical models for analysis of wave propagation in laminated, fiber and particle reinforced composites are surveyed. The anisotropic, dispersive and dissipative properties of stress pulses and shock waves in such materials are reviewed. A review of the behavior of composites under impact loading is presented along with the application of wave propagation concepts to the determination of impact stresses in composite plates.
Modeling wave impact on salt marsh boundaries Mara Tonelli,1,2
Fagherazzi, Sergio
Modeling wave impact on salt marsh boundaries Mara Tonelli,1,2 Sergio Fagherazzi,2 and Marco Petti1] Windwave attack is the fundamental cause of erosion of salt marsh boundaries. Tidal forcing acts as a proxy. Citation: Tonelli, M., S. Fagherazzi, and M. Petti (2010), Modeling wave impact on salt marsh boundaries, J
Variational Calculation on the Helium Atom Using a Trigonometric Trial Wave Function Frank Rioux
Rioux, Frank
Variational Calculation on the Helium Atom Using a Trigonometric Trial Wave Function Frank Rioux Chemistry Department CSB|SJU Trigonometric Trial Wave Function: r ,( ) 3 3 3 sech r( ):= Demonstrate the wave function is normalized. 0 r r ,( )2 4 r 2 d assume 0>, simplify 1 The terms
Monte Carlo comparison of quasielectron wave functions V. Melik-Alaverdian and N. E. Bonesteel
Bonesteel, Nicholas E.
Monte Carlo comparison of quasielectron wave functions V. Melik-Alaverdian and N. E. Bonesteel fractions 1/3, 1/5, and 1/7. For the quasielectron both the trial wave function originally proposed by Laughlin and the composite-fermion wave function proposed by Jain have been used. We find that for long
Monte Carlo Comparison of Quasielectron Wave Functions V. MelikAlaverdian and N. E. Bonesteel
Bonesteel, Nicholas E.
Monte Carlo Comparison of Quasielectron Wave Functions V. MelikÂAlaverdian and N. E. Bonesteel=3, 1/5, and 1/7. For the quasielectron both the trial wave function originally proposed by Laughlin and the composite fermion wave function proposed by Jain have been used. We find that for longÂrange Coulomb
Irregular wave functions of a hydrogen atom in a uniform magnetic field
NASA Technical Reports Server (NTRS)
Wintgen, D.; Hoenig, A.
1989-01-01
The highly excited irregular wave functions of a hydrogen atom in a uniform magnetic field are investigated analytically, with wave function scarring by periodic orbits considered quantitatively. The results obtained confirm that the contributions of closed classical orbits to the spatial wave functions vanish in the semiclassical limit. Their disappearance, however, is slow. This discussion is illustrated by numerical examples.
Variational Calculation on the Helium Atom Using a Hydrogenic Trial Wave Function Frank Rioux
Rioux, Frank
Variational Calculation on the Helium Atom Using a Hydrogenic Trial Wave Function Frank Rioux Chemistry Department CSB|SJU Gaussian Trial Wave Function: r ,( ) 3 exp - r( ):= Demonstrate the wave function is normalized. 0 r r ,( )2 4 r 2 d assume 0>, simplify 1 The terms
Accuracy of electronic wave functions in quantum Monte Carlo: The effect of high-order correlations
Nightingale, Peter
Accuracy of electronic wave functions in quantum Monte Carlo: The effect of high-order correlations, Rhode Island 02881 Received 24 February 1997; accepted 19 May 1997 Compact and accurate wave functions can be constructed by quantum Monte Carlo methods. Typically, these wave functions consist of a sum
Hertzian impact: experimental study of the force pulse and resulting stress waves.
McLaskey, Gregory C; Glaser, Steven D
2010-09-01
Ball impact has long been used as a repeatable source of stress waves in solids. The amplitude and frequency content of the waves are a function of the force-time history, or force pulse, that the ball imposes on the massive body. In this study, Glaser-type conical piezoelectric sensors are used to measure vibrations induced by a ball colliding with a massive plate. These measurements are compared with theoretical estimates derived from a marriage of Hertz theory and elastic wave propagation. The match between experiment and theory is so close that it not only facilitates the absolute calibration the sensors but it also allows the limits of Hertz theory to be probed. Glass, ruby and hardened steel balls 0.4 to 2.5 mm in diameter were dropped onto steel, glass, aluminum, and polymethylmethacrylate plates at a wide range of approach velocities, delivering frequencies up to 1.5 MHz into these materials. Effects of surface properties and yielding of the plate material were analyzed via the resulting stress waves and simultaneous measurements of the ball's coefficient of restitution. The sensors are sensitive to surface normal displacements down to about +/-1 pm in the frequency range of 20 kHz to over 1 MHz. PMID:20815445
The Wave Function of Vasiliev's Universe - A Few Slices Thereof
Dionysios Anninos; Frederik Denef; Daniel Harlow
2012-07-23
We study the partition function of the free Sp(N) conformal field theory recently conjectured to be dual to asymptotically de Sitter higher-spin gravity in four-dimensions. We compute the partition function of this CFT on a round sphere as a function of a finite mass deformation, on a squashed sphere as a function of the squashing parameter, and on an S2xS1 geometry as a function of the relative size of S2 and S1. We find that the partition function is divergent at large negative mass in the first case, and for small $S^1$ in the third case. It is globally peaked at zero squashing in the second case. Through the duality this partition function contains information about the wave function of the universe. We show that the divergence at small S1 occurs also in Einstein gravity if certain complex solutions are included, but the divergence in the mass parameter is new. We suggest an interpretation for this divergence as indicating an instability of de Sitter space in higher spin gravity, consistent with general arguments that de Sitter space cannot be stable in quantum gravity.
Love wave propagation in functionally graded piezoelectric material layer.
Du, Jianke; Jin, Xiaoying; Wang, Ji; Xian, Kai
2007-03-01
An exact approach is used to investigate Love waves in functionally graded piezoelectric material (FGPM) layer bonded to a semi-infinite homogeneous solid. The piezoelectric material is polarized in z-axis direction and the material properties change gradually with the thickness of the layer. We here assume that all material properties of the piezoelectric layer have the same exponential function distribution along the x-axis direction. The analytical solutions of dispersion relations are obtained for electrically open or short circuit conditions. The effects of the gradient variation of material constants on the phase velocity, the group velocity, and the coupled electromechanical factor are discussed in detail. The displacement, electric potential, and stress distributions along thickness of the graded layer are calculated and plotted. Numerical examples indicate that appropriate gradient distributing of the material properties make Love waves to propagate along the surface of the piezoelectric layer, or a bigger electromechanical coupling factor can be obtained, which is in favor of acquiring a better performance in surface acoustic wave (SAW) devices. PMID:17107699
Nucleon Excited State Wave Functions from Lattice QCD
Dale S. Roberts; Waseem Kamleh; Derek B. Leinweber
2013-11-26
We apply the eigenvectors from a variational analysis to successfully extract the wave functions of even-parity excited states of the nucleon, including the Roper. We explore the first four states in the spectrum excited by the standard nucleon interpolating field. We find that the states exhibit a structure qualitatively consistent with a constituent quark model, where the ground, first-, second- and third-excited states have 0, 1, 2, and 3 nodes in the radial wave function of the d-quark about two $u$ quarks at the origin. Moreover the radial amplitude of the probability distribution is similar to that predicted by constituent quark models. We present a detailed examination of the quark-mass dependence of the probability distributions for these states, searching for a nontrivial role for the multi-particle components mixed in the finite-volume QCD eigenstates. Finally we examine the dependence of the d-quark probability distribution on the positions of the two u quarks. The results are fascinating, with the underlying S-wave orbitals governing the distributions even at rather large u-quark separations.
Impact force identification in aerospace panels by an inverse ultrasonic guided wave problem
NASA Astrophysics Data System (ADS)
Bartoli, Ivan; Salamone, Salvatore; Lanza di Scalea, Francesco; Rhymer, Jennifer; Kim, Hyonny
2011-04-01
This paper deals with monitoring impacts on aluminum and composite aerospace panels. The specific problems addressed are (1) the identification of the impact forces (force magnitude time history) and (2) the discrimination of "damaging impacts" from "non-damaging impacts." Ultrasonic guided waves generated by the impacts are used as the sensing mechanism. Flexible Macro-Fiber Composite (MFC) patches are used as the ultrasonic receivers. The impact force identification method is based on an optimization routine which minimizes the difference between the experimental impact waves and the numerical impact waves calculated by a Semi-Analytical Finite Element (SAFE) forced analysis. The differentiation of "damaging impacts" vs. "non-damaging impacts" is based on a frequency analysis of the impact waves. These techniques are demonstrated through an extensive experimental testing program involving the following six specimens: an aluminum panel, a quasi-isotropic CFRP composite panel, a highly anisotropic CFRP composite panel, a stiffened aluminum panel, a stiffened quasi-isotropic CFRP composite panel, and a stiffened anisotropic CFRP composite panel. These panels were subjected to low-velocity hammer impacts and to high-velocity gas-gun impacts by ice projectiles at speeds up to 170 m/sec using UCSD's gas-gun test facility. In all of these experiments, the techniques summarized above gave excellent results for both impact force identification and impact force discrimination.
The Wave Function Behavior of the Open Topological String Partition Function on the Conifold
Amir-Kian Kashani-Poor
2007-04-19
We calculate the topological string partition function to all genus on the conifold, in the presence of branes. We demonstrate that the partition functions for different brane backgrounds (smoothly connected along a quantum corrected moduli space) can be interpreted as the same wave function in different polarizations. This behavior has a natural interpretation in the Chern-Simons target space description of the topological theory. Our detailed analysis however indicates that non-perturbatively, a modification of real Chern-Simons theory is required to capture the correct target space theory of the topological string. We perform our calculations in the framework of a free fermion representation of the open topological string, demonstrating that this framework extends beyond the simple C^3 geometry. The notion of a fermionic brane creation operator arises in this setting, and we study to what extent the wave function properties of the partition function can be extended to this operator.
Impact wave deposits provide new constraints on the location of the K/T boundary impact
NASA Technical Reports Server (NTRS)
Hildebrand, A. R.; Boynton, W. V.
1988-01-01
All available evidence is consistent with an impact into oceanic crust terminating the Cretaceous Period. Although much of this evidence is incompatible with an endogenic origin, some investigators still feel that a volcanic origin is possible for the Cretaceous/Tertiary (K/T) boundary clay layers. The commonly cited evidence for a large impact stems from delicate clay layers and their components and the impact site has not yet been found. Impact sites have been suggested all over the globe. The impact is felt to have occurred near North America by: the occurrence of a 2 cm thick ejecta layer only at North American locales, the global variation of shocked quartz grain sizes peaking in North America, the global variation of spinel compositions with most refractory compositions occurring in samples from the Pacific region and possibly uniquely severe plant extinctions in the North American region. The K/T boundary interval was investigated as preserved on the banks of the Brazos River, Texas. The K/T fireball and ejecta layers with associated geochemical anomalies were found interbedded with this sequence which apparently allows a temporal resolution 4 orders of magnitude greater than typical K/T boundary sections. A literature search reveals that such coarse deposits are widely preserved at the K/T boundary. Impact wave deposits have not been found elsewhere on the globe, suggesting the impact occurred between North and South America. The coarse deposits preserved in Deep Sea Drilling Project (DSDP) holes 151-3 suggest the impact occurred nearby. Subsequent tectonism has complicated the picture.
Green's function for SH-waves in a cylindrically monoclinic material
NASA Astrophysics Data System (ADS)
Watanabe, Kazumi; Payton, Robert G.
2002-11-01
Green's function for SH-waves in a cylindrically monoclinic material is considered for impulsive and time-harmonic sources. Closed form expressions for the Green's function are derived for a few limited values of anisotropic parameters. A very interesting time development of the wave front shape is illustrated and the wave front singularity is discussed for the transient SH-wave. Contours of the displacement amplitude for the time-harmonic wave are also shown.
Crustal structure of the Gamburtsev Mountains, East Antarctica, from S-wave receiver functions der Hilst Keywords: Gamburtsev Mountains Antarctica crustal structure S-wave receiver functions The Gamburtsev Subglacial Mountains (GSM), located in central East Antarctica, are one of the most enigmatic
Theory of steady-state plane tunneling-assisted impact ionization waves
Kyuregyan, A. S.
2013-07-15
The effect of band-to-band and trap-assisted tunneling on the properties of steady-state plane ionization waves in p{sup +}-n-n{sup +} structures is theoretically analyzed. It is shown that such tunneling-assisted impact ionization waves do not differ in a qualitative sense from ordinary impact ionization waves propagating due to the avalanche multiplication of uniformly distributed seed electrons and holes. The quantitative differences of tunneling-assisted impact ionization waves from impact ionization waves are reduced to a slightly different relation between the wave velocity u and the maximum field strength E{sub M} at the front. It is shown that disregarding impact ionization does not exclude the possibility of the existence of tunneling-assisted ionization waves; however, their structure radically changes, and their velocity strongly decreases for the same E{sub M}. A comparison of the dependences u(E{sub M}) for various ionization-wave types makes it possible to determine the conditions under which one of them is dominant. In conclusion, unresolved problems concerning the theory of tunneling-assisted impact ionization waves are discussed and the directions of further studies are outlined.
Birth weight impacts on wave reflections in children and adolescents.
Lurbe, Empar; Torro, Maria Isabel; Carvajal, Eva; Alvarez, Vicente; Redón, Josep
2003-03-01
The objective of the present study was to assess central aortic pressure and wave reflection in children and adolescents at different birth weights. Two hundred nineteen healthy children (126 girls), from 7 to 18 years of age (mean, 11.3 years) and born at term after a normotensive pregnancy, were included. The subjects were divided according to birth weight: <2.5 kg, from 2.5 to 2.999 kg, from 3.0 to 3.5 kg, and >3.5 kg. Pressure waveforms were recorded from the radial artery of the wrist, and the waveform data were then processed by the SphygmoCor radial/aortic transform software module to produce the estimated aortic pressure waveform. Augmentation index, an estimate of the pulse wave reflection, was significantly higher in children with the lowest birth weights compared with the other birth weight groups. In a multiple regression analysis, short stature, low heart rate, female gender, and lower birth weight had independent significant inverse correlations to the augmentation index when adjusted for diastolic blood pressure (R2=0.21). In summary, the results showed a relatively aged phenotype of large-vessel function in the children with the lowest birth weights. These early alterations may be amplified throughout life and may contribute to the increased cardiovascular risk associated with low birth weight. PMID:12623973
Modelling storm development and the impact when introducing waves, sea spray and heat fluxes
NASA Astrophysics Data System (ADS)
Wu, Lichuan; Rutgersson, Anna; Sahlée, Erik
2015-04-01
In high wind speed conditions, sea spray generated due to intensity breaking waves have big influence on the wind stress and heat fluxes. Measurements show that drag coefficient will decrease in high wind speed. Sea spray generation function (SSGF), an important term of wind stress parameterization in high wind speed, usually treated as a function of wind speed/friction velocity. In this study, we introduce a wave state depended SSGG and wave age depended Charnock number into a high wind speed wind stress parameterization (Kudryavtsev et al., 2011; 2012). The proposed wind stress parameterization and sea spray heat fluxes parameterization from Andreas et al., (2014) were applied to an atmosphere-wave coupled model to test on four storm cases. Compared with measurements from the FINO1 platform in the North Sea, the new wind stress parameterization can reduce the forecast errors of wind in high wind speed range, but not in low wind speed. Only sea spray impacted on wind stress, it will intensify the storms (minimum sea level pressure and maximum wind speed) and lower the air temperature (increase the errors). Only the sea spray impacted on the heat fluxes, it can improve the model performance on storm tracks and the air temperature, but not change much in the storm intensity. If both of sea spray impacted on the wind stress and heat fluxes are taken into account, it has the best performance in all the experiment for minimum sea level pressure and maximum wind speed and air temperature. Andreas, E. L., Mahrt, L., and Vickers, D. (2014). An improved bulk air-sea surface flux algorithm, including spray-mediated transfer. Quarterly Journal of the Royal Meteorological Society. Kudryavtsev, V. and Makin, V. (2011). Impact of ocean spray on the dynamics of the marine atmospheric boundary layer. Boundary-layer meteorology, 140(3):383-410. Kudryavtsev, V., Makin, V., and S, Z. (2012). On the sea-surface drag and heat/mass transfer at strong winds. Technical report, Royal Netherlands Meteorological Institute.
Realistic Nuclear Wave functions and Heavy Ion Collisions
M. Alvioli; C. Ciofi degli Atti; M. Strikman
2009-12-26
We discuss the implications of recent experimental evidence of nuclear Short Range Correlations (SRCs) on the modeling of the wave function of complex nuclei. We perform a calculation of potential energy contributions of pp and pn pairs in nuclei, showing that the presence of strong tensor correlations produce a ratio between the twos of about 1/9, which strongly deviates from the combinatorial counting of the number of pairs. We also discuss implications for the production of Monte Carlo configuration for the simulation of nuclear reactions involving complex nuclei.
Detecting Topological Order in a Ground State Wave Function
Levin, Michael; Wen Xiaogang
2006-03-24
A large class of topological orders can be understood and classified using the string-net condensation picture. These topological orders can be characterized by a set of data (N,d{sub i},F{sub lmn}{sup ijk},{delta}{sub ijk}). We describe a way to detect this kind of topological order using only the ground state wave function. The method involves computing a quantity called the 'topological entropy' which directly measures the total quantum dimension D=id{sub i}{sup 2}.
Chameleon fields, wave function collapse and quantum gravity
NASA Astrophysics Data System (ADS)
Zanzi, A.
2015-07-01
Chameleon fields are quantum (usually scalar) fields, with a density-dependent mass. In a high-density environment, the mass of the chameleon is large. On the contrary, in a small-density environment (e.g. on cosmological distances), the chameleon is very light. A model where the collapse of the wave function is induced by chameleon fields is presented. During this analysis, a Chameleonic Equivalence Principle (CEP) will be formulated: in this model, quantum gravitation is equivalent to a conformal anomaly. Further research efforts are necessary to verify whether this proposal is compatible with phenomeno logical constraints.
Is spontaneous wave function collapse testable at all?
NASA Astrophysics Data System (ADS)
Diósi, Lajos
2015-07-01
Mainstream literature on spontaneous wave function collapse never reflects on or profits from the formal coincidence and conceptual relationship with standard collapse under time-continuous quantum measurement (monitoring). I propose some easy lessons of standard monitoring theory which would make spontaneous collapse models revise some of their claims. In particular, the objective detection of spontaneous collapse remains impossible as long as the correct identification of what corresponds to the signal in standard monitoring is missing from spontaneous collapse models, the physical detectability of the “signal” is not stated explicitly and, finally, the principles of physical detection are not revealed.
Asymmetry in Directional Spreading Function of Random Waves due to Refraction
Haller, Merrick
Asymmetry in Directional Spreading Function of Random Waves due to Refraction Changhoon Lee1 ; Jae due to wave refraction. The asymmetry created by refraction increases with the offshore peak wave and is shown to better capture changes in the directional distribution that occur in a refracting, random wave
Big bounce as scattering of wave function at big crunch
Fumitoshi Amemiya; Tatsuhiko Koike
2010-08-19
A gauge-invariant quantum theory of the Friedmann-Robertson-Walker (FRW) universe with dust is studied in terms of the Ashtekar variables. We use the reduced phase space quantization which has following advantages: (i) fundamental variables are all gauge invariant, (ii) there exists a physical time evolution of gauge-invariant quantities, so that the problem of time is absent and (iii) the reduced phase space can be quantized in the same manner as in ordinary quantum mechanics. In the FRW model, the dynamical components of the Ashtekar variables are given by a single quantity $p$ and its conjugate momentum, where $p$ is related to the scale factor $a$ as $a\\propto \\sqrt{|p|}$ and its sign gives the orientation of triads. We solve a scattering problem in terms of ingoing and outgoing energy eigenstates. We show that the incident wave is reflected in rate $1/4$ and transmitted in rate $3/4$ at the classical singularity $p=0$. Analyzing the dynamics of a wave packet, we show that the classical initial singularity is replaced by a big bounce in quantum theory. A possible interpretation of the result is that the wave function of the universe has been in a superposition of states representing right-handed and left-handed systems before the big bounce.
The impact of heat waves on children's health: a systematic review.
Xu, Zhiwei; Sheffield, Perry E; Su, Hong; Wang, Xiaoyu; Bi, Yan; Tong, Shilu
2014-03-01
Young children are thought to be particularly sensitive to heat waves, but relatively less research attention has been paid to this field to date. A systematic review was conducted to elucidate the relationship between heat waves and children's health. Literature published up to August 2012 were identified using the following MeSH terms and keywords: "heatwave", "heat wave", "child health", "morbidity", "hospital admission", "emergency department visit", "family practice", "primary health care", "death" and "mortality". Of the 628 publications identified, 12 met the selection criteria. The existing literature does not consistently suggest that mortality among children increases significantly during heat waves, even though infants were associated with more heat-related deaths. Exposure to heat waves in the perinatal period may pose a threat to children's health. Pediatric diseases or conditions associated with heat waves include renal disease, respiratory disease, electrolyte imbalance and fever. Future research should focus on how to develop a consistent definition of a heat wave from a children's health perspective, identifying the best measure of children's exposure to heat waves, exploring sensitive outcome measures to quantify the impact of heat waves on children, evaluating the possible impacts of heat waves on children's birth outcomes, and understanding the differences in vulnerability to heat waves among children of different ages and from different income countries. Projection of the children's disease burden caused by heat waves under climate change scenarios, and development of effective heat wave mitigation and adaptation strategies that incorporate other child protective health measures, are also strongly recommended. PMID:23525899
The impact of heat waves on children's health: a systematic review
NASA Astrophysics Data System (ADS)
Xu, Zhiwei; Sheffield, Perry E.; Su, Hong; Wang, Xiaoyu; Bi, Yan; Tong, Shilu
2014-03-01
Young children are thought to be particularly sensitive to heat waves, but relatively less research attention has been paid to this field to date. A systematic review was conducted to elucidate the relationship between heat waves and children's health. Literature published up to August 2012 were identified using the following MeSH terms and keywords: "heatwave", "heat wave", "child health", "morbidity", "hospital admission", "emergency department visit", "family practice", "primary health care", "death" and "mortality". Of the 628 publications identified, 12 met the selection criteria. The existing literature does not consistently suggest that mortality among children increases significantly during heat waves, even though infants were associated with more heat-related deaths. Exposure to heat waves in the perinatal period may pose a threat to children's health. Pediatric diseases or conditions associated with heat waves include renal disease, respiratory disease, electrolyte imbalance and fever. Future research should focus on how to develop a consistent definition of a heat wave from a children's health perspective, identifying the best measure of children's exposure to heat waves, exploring sensitive outcome measures to quantify the impact of heat waves on children, evaluating the possible impacts of heat waves on children's birth outcomes, and understanding the differences in vulnerability to heat waves among children of different ages and from different income countries. Projection of the children's disease burden caused by heat waves under climate change scenarios, and development of effective heat wave mitigation and adaptation strategies that incorporate other child protective health measures, are also strongly recommended.
Li, Yong; Fang, Hui; Min, Changjun; Yuan, Xiaocong
2015-01-01
Under the usual approximation of treating a biological particle as a spheroidal droplet, we consider the analysis of its size and shape with the high frequency photoacoustics and develop a numerical method which can simulate its characteristic photoacoustic waves. This numerical method is based on the calculation of spheroidal wave functions, and when comparing to the finite element model (FEM) calculation, can reveal more physical information and can provide results independently at each spatial points. As the demonstration, red blood cells (RBCs) and MCF7 cell nuclei are studied, and their photoacoustic responses including field distribution, spectral amplitude, and pulse forming are calculated. We expect that integrating this numerical method with the high frequency photoacoustic measurement will form a new modality being extra to the light scattering method, for fast assessing the morphology of a biological particle. PMID:26442830
NASA Astrophysics Data System (ADS)
Li, Yong; Fang, Hui; Min, Changjun; Yuan, Xiaocong
2015-10-01
Under the usual approximation of treating a biological particle as a spheroidal droplet, we consider the analysis of its size and shape with the high frequency photoacoustics and develop a numerical method which can simulate its characteristic photoacoustic waves. This numerical method is based on the calculation of spheroidal wave functions, and when comparing to the finite element model (FEM) calculation, can reveal more physical information and can provide results independently at each spatial points. As the demonstration, red blood cells (RBCs) and MCF7 cell nuclei are studied, and their photoacoustic responses including field distribution, spectral amplitude, and pulse forming are calculated. We expect that integrating this numerical method with the high frequency photoacoustic measurement will form a new modality being extra to the light scattering method, for fast assessing the morphology of a biological particle.
Li, Yong; Fang, Hui; Min, Changjun; Yuan, Xiaocong
2015-01-01
Under the usual approximation of treating a biological particle as a spheroidal droplet, we consider the analysis of its size and shape with the high frequency photoacoustics and develop a numerical method which can simulate its characteristic photoacoustic waves. This numerical method is based on the calculation of spheroidal wave functions, and when comparing to the finite element model (FEM) calculation, can reveal more physical information and can provide results independently at each spatial points. As the demonstration, red blood cells (RBCs) and MCF7 cell nuclei are studied, and their photoacoustic responses including field distribution, spectral amplitude, and pulse forming are calculated. We expect that integrating this numerical method with the high frequency photoacoustic measurement will form a new modality being extra to the light scattering method, for fast assessing the morphology of a biological particle. PMID:26442830
IMPACTS OF URBANIZATION ON WATERSHED HYDROLOGIC FUNCTION
Technology Transfer Automated Retrieval System (TEKTRAN)
Although urbanization has a major impact on watershed hydrology, there have not been studies to quantify basic hydrological relationships are altered by the addition of impervious surfaces. The USDA-ARS and USEPA-ORD-NRMRL have initiated a pilot program to study the impacts of different extents and...
Stress wave propagation in a composite beam subjected to transverse impact.
Lu, Wei-Yang; Song, Bo; Jin, Huiqing
2010-08-01
Composite materials, particularly fiber reinforced plastic composites, have been extensively utilized in many military and industrial applications. As an important structural component in these applications, the composites are often subjected to external impact loading. It is desirable to understand the mechanical response of the composites under impact loading for performance evaluation in the applications. Even though many material models for the composites have been developed, experimental investigation is still needed to validate and verify the models. It is essential to investigate the intrinsic material response. However, it becomes more applicable to determine the structural response of composites, such as a composite beam. The composites are usually subjected to out-of-plane loading in applications. When a composite beam is subjected to a sudden transverse impact, two different kinds of stress waves, longitudinal and transverse waves, are generated and propagate in the beam. The longitudinal stress wave propagates through the thickness direction; whereas, the propagation of the transverse stress wave is in-plane directions. The longitudinal stress wave speed is usually considered as a material constant determined by the material density and Young's modulus, regardless of the loading rate. By contrast, the transverse wave speed is related to structural parameters. In ballistic mechanics, the transverse wave plays a key role to absorb external impact energy [1]. The faster the transverse wave speed, the more impact energy dissipated. Since the transverse wave speed is not a material constant, it is not possible to be calculated from stress-wave theory. One can place several transducers to track the transverse wave propagation. An alternative but more efficient method is to apply digital image correlation (DIC) to visualize the transverse wave propagation. In this study, we applied three-pointbending (TPB) technique to Kolsky compression bar to facilitate dynamic transverse loading on a glass fiber/epoxy composite beam. The high-speed DIC technique was employed to study the transverse wave propagation.
Excitation of Jovian seismic waves by the Shoemaker-Levy 9 cometary impact
NASA Astrophysics Data System (ADS)
Lognonne, P.; Mosser, B.; Dahlen, F. A.
1994-08-01
The kinetic energy released by the collision of the comet Shoemaker-Levy 9 with Jupiter is expected to be between 1020 J and 1023 J. This energy will excite seismic waves, which will propagate within Jupiter. These seismic waves are computed by summing normal modes of degree l up to 1400 and frequency nu up to 10 mHz. The excitation amplitudes are obtained using a model of the blast wave induced by the explosion of the comet. Keeping in mind the possible detection of the waves with an IR camera, we examine the thermal signature of the global modes and transient waves excited by the impact. We show that the excitation of surface waves and normal modes will produce a directly observable signal for strong impacts only. An impact with an energy greater than 2.8 x 1021 J will produce a 10-mHz frequency P wave with associated peak-to-peak temperature fluctuations greater than 0.01 K at the antipode. Surface waves with frequencies less than 3 mHz will give rise to fluctuations everywhere in excess of 0.01 K for impacts greater than 9 x 1022 J. Lower energy impacts will not be directly detectable, the signal-to-noise ratio on a single pixel of the camera being too low. Stacking methods might enable the detection of P waves generated by impacts with energies as low as 7.25 x 1020 J at Delta = 90 deg and of surface waves generated by impacts as low as 1.4 x 1021 J. High-frequency monitoring of the temperature in the jovian troposphere during at least 2 hr after each impact, and low-frequency monitoring during the remaining observation time may provide unique information on the inner structure of Jupiter, including the core and the discontinuity due to the possible plasma phase transition of hydrogen.
Climate change impact on wave energy in the Persian Gulf
NASA Astrophysics Data System (ADS)
Kamranzad, Bahareh; Etemad-Shahidi, Amir; Chegini, Vahid; Yeganeh-Bakhtiary, Abbas
2015-06-01
Excessive usage of fossil fuels and high emission of greenhouse gases have increased the earth's temperature, and consequently have changed the patterns of natural phenomena such as wind speed, wave height, etc. Renewable energy resources are ideal alternatives to reduce the negative effects of increasing greenhouse gases emission and climate change. However, these energy sources are also sensitive to changing climate. In this study, the effect of climate change on wave energy in the Persian Gulf is investigated. For this purpose, future wind data obtained from CGCM3.1 model were downscaled using a hybrid approach and modification factors were computed based on local wind data (ECMWF) and applied to control and future CGCM3.1 wind data. Downscaled wind data was used to generate the wave characteristics in the future based on A2, B1, and A1B scenarios, while ECMWF wind field was used to generate the wave characteristics in the control period. The results of these two 30-yearly wave modelings using SWAN model showed that the average wave power changes slightly in the future. Assessment of wave power spatial distribution showed that the reduction of the average wave power is more in the middle parts of the Persian Gulf. Investigation of wave power distribution in two coastal stations (Boushehr and Assalouyeh ports) indicated that the annual wave energy will decrease in both stations while the wave power distribution for different intervals of significant wave height and peak period will also change in Assalouyeh according to all scenarios.
Ghost wave-function renormalization in Asymptotically Safe Quantum Gravity
Kai Groh; Frank Saueressig
2010-01-28
Motivated by Weinberg's asymptotic safety scenario, we investigate the gravitational renormalization group flow in the Einstein-Hilbert truncation supplemented by the wave-function renormalization of the ghost fields. The latter induces non-trivial corrections to the beta-functions for Newton's constant and the cosmological constant. The resulting ghost-improved phase diagram is investigated in detail. In particular, we find a non-trivial ultraviolet fixed point in agreement with the asymptotic safety conjecture, which also survives in the presence of extra dimensions. In four dimensions the ghost anomalous dimension at the fixed point is $\\eta_c^* = -1.8$, supporting space-time being effectively two-dimensional at short distances.
[Approach to recognition of ECG P waves based on approximating functions].
Yang, Z; Li, L; Ling, J
1998-06-01
A new method of recognizing ECG P waves based on approximating function is presented in this paper. The result of experiment demonstrates that the method based on the second order approximating functions to recognize P waves in useful and easy to do. The rate of correctness for recognizing P waves is higher than 99% according to MIT/BIH ECG Datebase. PMID:12548896
Early heat waves over Italy and their impacts on durum wheat yields
NASA Astrophysics Data System (ADS)
Fontana, G.; Toreti, A.; Ceglar, A.; De Sanctis, G.
2015-07-01
In the last decades the Euro-Mediterranean region has experienced an increase in extreme temperature events such as heat waves. These extreme weather conditions can strongly affect arable crop growth and final yields. Here, early heat waves over Italy from 1995 to 2013 are identified and characterised and their impact on durum wheat yields is investigated. As expected, results confirm the impact of the 2003 heat wave and highlight a high percentage of concurrence of early heat waves and significant negative yield anomalies in 13 out of 39 durum wheat production areas. In south-eastern Italy (the most important area for durum wheat production), the percentage of concurrent events exceeds 80 %.
Early heat waves over Italy and their impacts on durum wheat yields
NASA Astrophysics Data System (ADS)
Fontana, G.; Toreti, A.; Ceglar, A.; De Sanctis, G.
2015-05-01
In the last decades the Euro-Mediterranean region has experienced an increase in extreme temperature events such as heat waves. These extreme weather conditions can strongly affect arable crop growth and final yields. Here, early heat waves over Italy from 1995 to 2013 are identified and characterised and their impact on durum wheat yields is investigated. As expected, results confirm the impact of the 2003 heat waves and highlight a high percentage of concurrence of early heat waves and significant negative yield anomalies in 13 out of 39 durum wheat production areas. In south-eastern Italy (the most important area for durum wheat production), the percentage of concurrent events exceeds 80%.
Ezzedine, Souheil M.; Lomov, Ilya; Miller, Paul L.; Dennison, Deborah S.; Dearborn, David S.; Antoun, Tarabay H.
2015-05-19
As part of a larger effort involving members of several other organizations, we have conducted numerical simulations in support of emergency-response exercises of postulated asteroid ocean impacts. We have addressed the problem from source (asteroid entry) to ocean impact (splash) to wave generation, propagation and interaction with the U.S. shoreline. We simulated three impact sites. The first site is located off the east coast by Maryland's shoreline. The second site is located off of the West coast, the San Francisco bay. The third set of sites are situated in the Gulf of Mexico. Asteroid impacts on the ocean surface aremore »conducted using LLNL's hydrocode GEODYN to create the impact wave source for the shallow water wave propagation code, SWWP, a shallow depth averaged water wave code.« less
Ezzedine, Souheil M.; Lomov, Ilya; Miller, Paul L.; Dennison, Deborah S.; Dearborn, David S.; Antoun, Tarabay H.
2015-05-19
As part of a larger effort involving members of several other organizations, we have conducted numerical simulations in support of emergency-response exercises of postulated asteroid ocean impacts. We have addressed the problem from source (asteroid entry) to ocean impact (splash) to wave generation, propagation and interaction with the U.S. shoreline. We simulated three impact sites. The first site is located off the east coast by Maryland's shoreline. The second site is located off of the West coast, the San Francisco bay. The third set of sites are situated in the Gulf of Mexico. Asteroid impacts on the ocean surface are conducted using LLNL's hydrocode GEODYN to create the impact wave source for the shallow water wave propagation code, SWWP, a shallow depth averaged water wave code.
Measuring electron wave functions in nanostructures via photoemission
NASA Astrophysics Data System (ADS)
Ortega, Enrique; Mugarza, Aitor; Garcia de Abajo, Javier; Kuntze, Jens; Himpsel, Franz
2004-03-01
Vicinal noble metal surfaces with regular arrays of straight steps and flat terraces can be used as model lateral superlattices to understand their basic electronic properties by means of photoemission. Here we focus on samples that display surface electron confinement within high index oriented terraces, i.e., lateral quantum well states. The photoemission intensity displays angular dependence in the direction perpendicular to the steps as expected for infinite, one-dimensional quantum wells [1]. In a first approach, such intensity represents the square modulus of the quantum well wave function in reciprocal space. Furthermore, the corresponding electron wave function in real space can be recovered applying an iterative formalism used in x-ray diffraction and called oversampling [2]. The method has been tested in Au(111) vicinal surfaces with regular arrays of monatomic steps, and further applied to faceted Cu(111) surfaces that also display lateral quantum wells. [1] A. Mugarza., A. Mascaraque, V. Pérez-Dieste, V. Repain, S. Rousset, F. J. García de Abajo, and J. E. Ortega, Phys. Rev. Lett. 87, 107601 (2001). [2] A. Mugarza, J. E. Ortega , F. J. Himpsel, and F. J. García de Abajo, Phys. Rev. B 67, 081404 (2003).
Propagation of impact-induced shock waves in porous sandstone using mesoscale modeling
NASA Astrophysics Data System (ADS)
GÜLdemeister, Nicole; WÜNnemann, Kai; Durr, Nathanael; Hiermaier, Stefan
2013-01-01