Semi-classical signal analysis
Laleg-Kirati, Taous-Meriem; Cré peau, Emmanuelle; Sorine, Michel
2012-01-01
This study introduces a new signal analysis method, based on a semi-classical approach. The main idea in this method is to interpret a pulse-shaped signal as a potential of a Schrödinger operator and then to use the discrete spectrum
Semi-classical signal analysis
Laleg-Kirati, Taous-Meriem
2012-09-30
This study introduces a new signal analysis method, based on a semi-classical approach. The main idea in this method is to interpret a pulse-shaped signal as a potential of a Schrödinger operator and then to use the discrete spectrum of this operator for the analysis of the signal. We present some numerical examples and the first results obtained with this method on the analysis of arterial blood pressure waveforms. © 2012 Springer-Verlag London Limited.
Semi-classical quantization of chaotic billiards
International Nuclear Information System (INIS)
Smilansky, U.
1992-02-01
The semi-classical quantization of chaotic billiards will be developed using scattering theory approach. This will be used to introduce and explain the inherent difficulties in the semi-classical quantization of chaos, and to show some of the modern tools which were developed recently to overcome these difficulties. To this end, we shall first obtain a semi-classical secular equation which is based on a finite number of classical periodic orbits. We shall use it to derive some spectral properties, and in particular to investigate the relationship between spectral statistics of quantum chaotic systems and the predictions of random-matrix theory. We shall finally discuss an important family of chaotic billiard, whose statistics does not follow any of the canonical ensembles, (GOE,GUE,...) but rather, corresponds to a new universality class. (author)
Classical, Semi-classical and Quantum Noise
Poor, H; Scully, Marlan
2012-01-01
David Middleton was a towering figure of 20th Century engineering and science and one of the founders of statistical communication theory. During the second World War, the young David Middleton, working with Van Fleck, devised the notion of the matched filter, which is the most basic method used for detecting signals in noise. Over the intervening six decades, the contributions of Middleton have become classics. This collection of essays by leading scientists, engineers and colleagues of David are in his honor and reflect the wide influence that he has had on many fields. Also included is the introduction by Middleton to his forthcoming book, which gives a wonderful view of the field of communication, its history and his own views on the field that he developed over the past 60 years. Focusing on classical noise modeling and applications, Classical, Semi-Classical and Quantum Noise includes coverage of statistical communication theory, non-stationary noise, molecular footprints, noise suppression, Quantum e...
Dispersions in Semi-Classical Dynamics
International Nuclear Information System (INIS)
Zielinska-Pfabe, M.; Gregoire, C.
1987-01-01
Dispersions around mean values of one-body observables are obtained by restoring classical many-body correlations in Vlasov and Landau-Vlasov dynamics. The method is applied to the calculation of fluctuations in mass, charge and linear momentum in heavy-ion collisions. Results are compared to those obtained by the Balian-Veneroni variational principle in semi-classical approximation
The Wigner transform and the semi-classical approximations
International Nuclear Information System (INIS)
Shlomo, S.
1985-01-01
The Wigner transform provides a reformulation of quantum mechanics in terms of classical concepts. Some properties of the Wigner transform of the density matrix which justify its interpretation as the quantum-mechanical analog of the classical phase-space distribution function are presented. Considering some applications, it is demonstrated that the Wigner distribution function serves as a good starting point for semi-classical approximations to properties of the (nuclear) many-body system
Pairing effects in rotating nuclei: a semi classical approach
International Nuclear Information System (INIS)
Durand, M.
1985-10-01
The semi-classical phase-space distribution ρ(r,p) is calculated for rotating superfluid nuclei, taking into account the reaction of the pairing field to the rotational motion. Moments of inertia and current distributions calculated by means of this distribution pass continuously from a rigid to an irrotational behaviour
Semi-classical limit of relativistic quantum mechanics
Indian Academy of Sciences (India)
It is shown that the semi-classical limit of solutions to the Klein–Gordon equation gives the particle probability density that is in direct proportion to the inverse of the particle velocity. It is also shown that in the case of the Dirac equation a different result is obtained.
The semi classical laser theory and some applications of laser
International Nuclear Information System (INIS)
Abdalla, Abbaker Ali
1995-04-01
The semi classical laser theory is concerned with the interaction between light and matter in such a way that the matter is treated quantum-mechanically whereas light is treated in terms of the classical electromagnetic equations. In this work the Maxwell-Bloch equations are employed to describe the interaction between light and matter. Applications of the theory as well as different types of lasers are reviewed. (Author)
Microscopic and semi-classical treatments of octupole deformation in the light actinides
International Nuclear Information System (INIS)
Chasman, R.R.
1984-01-01
Microscopic and semi-classical descriptions of octupole deformation are compared. New semi-classical results, obtained with the use of a Woods-Saxon potential are presented. Comparisons with experiment are made. 21 references
Semi classical model of the neutron resonance compound nucleus
International Nuclear Information System (INIS)
Ohkubo, Makio
1995-01-01
A Semi-classical model of compound nucleus is developed, where time evolution and recurrence for many degrees of freedom (oscillators) excited simultaneously are explicitly considered. The effective number of oscillators plays the role in the compound nucleus, and the nuclear temperatures are derived, which are in good agreement with the traditional values. Time structures of the compound nucleus at resonance are considered, from which equidistant level series with an envelope of strength function of giant resonance nature is obtained. S-matrix formulation for fine structure resonance is derived. (author)
Semi-classical approximation to path integrals - phases and catastrophes
International Nuclear Information System (INIS)
Levit, S.
1977-01-01
Problems of phases and catastrophes were encountered when trying to apply the classical S-matrix theory to the scattering phenomena in nuclear physics. The path integral formulation provided a suitable basis for the treatment of these and related problems. Within conventional mathematical language it was possible to give practical prescriptions and discuss their limitations. Since the semi-classical (stationary phase) approximation is commonly used in any application of the path integral method, the results are not restricted to the scattering problems and may be of general interest. The derivation of the uniform approximations in the energy representation should use the exact path integral expression as the starting point, rather than performing Fourier transforms on the expressions derived in the present lecture. (B.G.)
On semi-classical questions related to signal analysis
Helffer, Bernard
2011-12-01
This study explores the reconstruction of a signal using spectral quantities associated with some self-adjoint realization of an h-dependent Schrödinger operator -h2(d2/dx2)-y(x), h>0, when the parameter h tends to 0. Theoretical results in semi-classical analysis are proved. Some numerical results are also presented. We first consider as a toy model the sech2 function. Then we study a real signal given by arterial blood pressure measurements. This approach seems to be very promising in signal analysis. Indeed it provides new spectral quantities that can give relevant information on some signals as it is the case for arterial blood pressure signal. © 2011 - IOS Press and the authors. All rights reserved.
Improvements on Semi-Classical Distorted-Wave model
Energy Technology Data Exchange (ETDEWEB)
Sun Weili; Watanabe, Y.; Kuwata, R. [Kyushu Univ., Fukuoka (Japan); Kohno, M.; Ogata, K.; Kawai, M.
1998-03-01
A method of improving the Semi-Classical Distorted Wave (SCDW) model in terms of the Wigner transform of the one-body density matrix is presented. Finite size effect of atomic nuclei can be taken into account by using the single particle wave functions for harmonic oscillator or Wood-Saxon potential, instead of those based on the local Fermi-gas model which were incorporated into previous SCDW model. We carried out a preliminary SCDW calculation of 160 MeV (p,p`x) reaction on {sup 90}Zr with the Wigner transform of harmonic oscillator wave functions. It is shown that the present calculation of angular distributions increase remarkably at backward angles than the previous ones and the agreement with the experimental data is improved. (author)
Semi-classical theory of fluctuations in nuclear matter
International Nuclear Information System (INIS)
Benhassine, B.
1994-01-01
At intermediate energies the heavy ion collisions can be studied within the framework of a semi-classical approach based on the Vlasov-Uehling-Uhlenbeck (VUU) equation. Such an approach reduces the N-body problem to its description in terms of the one-body distribution function and constitutes the basis of several successful simulation models. Our aim in this work is to extend these average approaches to treat fluctuations. Within the framework of a linear approximation, we derived a Fokker-Planck transport equation in the one-body phase space. When it is reduced to its first moments, one recovers the VUU equation for the average dynamics together with the time evolution equation for the correlations. The collective transport coefficients are then obtained by projection on the one-body collective space. Independently, using a projection method introduced by Van Kampen, based on the constants of motion, we deduce the stationary expressions for the covariance matrix in phase space. We extract then, the equilibrium dispersions of one-body observables in a homogeneous case and in a spherical symmetric one. These results are compared with two types of simulation models in a relaxation time approximation. In the first one which is of Lagrangian type, the collective transport coefficients are directly extracted from the simulation and consequently the numerical fluctuations are washed out. The second model, due to its Eulerian character, allows us to make a microscopical comparison. (author)
Classical and semi-classical solutions of the Yang--Mills theory
International Nuclear Information System (INIS)
Jackiw, R.; Nohl, C.; Rebbi, C.
1977-12-01
This review summarizes what is known at present about classical solutions to Yang-Mills theory both in Euclidean and Minkowski space. The quantal meaning of these solutions is also discussed. Solutions in Euclidean space expose multiple vacua and tunnelling of the quantum theory. Those in Minkowski space-time provide a semi-classical spectrum for a conformal generator
A semi-classical analysis of Dirac fermions in 2+1 dimensions
International Nuclear Information System (INIS)
Maiti, Moitri; Shankar, R
2012-01-01
We investigate the semi-classical dynamics of massless Dirac fermions in 2+1 dimensions in the presence of external electromagnetic fields. By generalizing the α matrices by two generators of the SU(2) group in the (2S + 1)-dimensional representation and doing a certain scaling, we formulate an S → ∞ limit where the orbital and the spinor degrees become classical. We solve for the classical trajectories for a free particle on a cylinder and a particle in a constant magnetic field. We compare the semi-classical spectrum, obtained by Bohr–Sommerfeld quantization with the exact quantum spectrum for low values of S. For the free particle, the semi-classical spectrum is exact. For the particle in a constant magnetic field, the semi-classical spectrum reproduces all the qualitative features of the exact quantum spectrum at all S. The quantitative fit for S = 1/2 is reasonably good. (paper)
A new approach to the semi-classical relativistic two-body problem for charged fermions
International Nuclear Information System (INIS)
Leiter, D.
1978-01-01
Generalizing from a recently developed hybrid formulation of classical electrodynamics with ''direct (charge-field) action'' structure an analogous semi-classical Dirac formulation of the theory is constructed, which is capable of describing the semi-classical quantum mechanics of two identical spin-1/2 particles. This semi-classical formulation is to be used as a heuristic aid in searching for the theoretical structure of a fully ''second quantized'' theory. The Pauli exclusion principle is incorporated by making the interaction fields (in the action principle) antisymmetric with respect to ''charge-field'' labeling. In this manner, ''position correlation'' effects associated with ''configuration interaction'' can also be accounted for. By studying the nature of the stationary-state solutions, the formalism is compared with the conventional quantum-mechanical one (to understand the similarities and the differences between this approach and the usual correlated Hartree-Fock approximation of ordinary relativistic quantum theory). The stationary-state solutions to the semi-classical formalism are shown to closely approximate the usual quantum-mechanical solutions when the wave functions are represented as a superposition of Slater determinants of Dirac-Coulombic-type wave functions with radial parts having a form which extremizes the total Breit energy. The manner in which this semi-classical theory might be extended to a fully ''second quantized'' formalism is sketched. (author)
Semi-classical analysis of optical model ambiguities
International Nuclear Information System (INIS)
Cuer, M.
1979-01-01
The ambiguities in the inverse problem at fixed energy in quantum mechanics are analyzed in the framework of the JWKB method. When the classical turning point is unique for all values of the impact parameter (high energies region), the ambiguities proceed only from the quantization of the angular momentum. In the asymptotic region the difference between two particular equivalent potentials changes sign infinitely often. In addition, the set of equivalent potentials which have a given asymptotic form is bounded (except perhaps at the origin). When there are several turning points for small values of the impact parameter (low-energy region), new ambiguities arise from the fact that the parts of the potential that are located between turning points are not ''visible'' in the classical limit. The set of equivalent potentials wich have a given asymptotic form is then not bounded. Mumerical examples (of real and complex equivalent potentials) are given. The optical model ambiguities are studied. The potential depth ambiguities also appear in classical mechanics, but their discrete nature is a quantum property. The VR/sup p//sup( V/)=constant ambiguities can be explained by the quantum corrections to the spiral scattering phenomenon. An attempt to explain why ambiguities arise only with heavy particles scattering is also given
A derivation of the Derbenev-Kondratenko formula using semi-classical electrodynamics
International Nuclear Information System (INIS)
Mane, S.R.
1985-11-01
We present a detailed exposition of the mechanism for the build-up of polarization in electron storage rings. A semi-classical approach is used to derive the rate of growth and asymptotic degree of polarization in an electron storage ring (the Derbenev-Kondratenko formula). Statistical mechanical concepts used to obtain as classical an understanding as possible of this phenomenon. (orig.)
Pure state condition for the semi-classical Wigner function
International Nuclear Information System (INIS)
Ozorio de Almeida, A.M.
1982-01-01
The Wigner function W(p,q) is a symmetrized Fourier transform of the density matrix e(q 1 ,q 2 ), representing quantum-mechanical states or their statistical mixture in phase space. Identification of these two alternatives in the case of density matrices depends on the projection identity e 2 = e; its Wigner correspondence is the pure state condition. This criterion is applied to the Wigner functions botained from standard semiclassical wave functions, determining as pure states those whose classical invariant tori satisfy the generalized Bohr-Sommerfeld conditions. Superpositions of eigenstates are then examined and it is found that the Wigner function corresponding to Gaussian random wave functions are smoothed out in the manner of mixedstate Wigner functions. Attention is also given to the pure-state condition in the case where an angular coordinate is used. (orig.)
Effective state metamorphosis in semi-classical loop quantum cosmology
Energy Technology Data Exchange (ETDEWEB)
Singh, Parampreet [Institute for Gravitational Physics and Geometry, Pennsylvania State University, University Park, PA 16802 (United States)
2005-10-21
Modification to the behaviour of geometrical density at short scales is a key result of loop quantum cosmology, responsible for an interesting phenomenology in the very early universe. We demonstrate the way matter with arbitrary scale factor dependence in Hamiltonian incorporates this change in its effective dynamics in the loop-modified phase. For generic matter, the equation of state starts varying near a critical scale factor, becomes negative below it and violates the strong energy condition. This opens a new avenue to generalize various phenomenological applications in loop quantum cosmology. We show that different ways to define energy density may yield radically different results, especially for the case corresponding to classical dust. We also discuss implications for frequency dispersion induced by modification to geometric density at small scales.
Semi-classical behavior of Poschl-Teller coherent states
Czech Academy of Sciences Publication Activity Database
Bergeron, H.; Gazeau, J.P.; Siegl, Petr; Youssef, A.
2010-01-01
Roč. 92, č. 6 (2010), s. 60003 ISSN 0295-5075 R&D Projects: GA MŠk LC06002 Institutional research plan: CEZ:AV0Z10480505 Institutional support: RVO:61389005 Keywords : coherent states * Pöschl-Teller potential * quantization Subject RIV: BE - Theoretical Physics Impact factor: 2.753, year: 2010
Evasive levels in quantisation through wavepacket coupling: a semi-classical investigation
International Nuclear Information System (INIS)
Amiot, P.; Giraud, B.
1984-01-01
A new method is presented to introduce classical mechanics elements into the problem of obtaining the spectrum of an operator H-circumflex(p-circumflex, q-circumflex). A finite-rank functional space is created by centering complex wavepackets on a discrete number of points on an equi-energy of the classical H(p,q) and by placing real wavepackets in the classically forbidden region. The latter span the active subspace, P, and the former the inactive subspace, Q, for an application of the method of Bloch-Horowitz. A semi-classical study of the Green function in the inactive subspace Q, classically allowed, gives a clear explanation of this phenomenon and sheds new light on the significance of this semi-classical approximation for the propagator. An extension to the problem of barrier penetration is proposed. (author)
A uniform semi-classical approach to the Coulomb fission problem
International Nuclear Information System (INIS)
Levit, S.; Smilansky, U.
1978-01-01
A semi-classical theory based on the path integral formalism is applied to the description of Coulomb fission. Complex classical trajectories are used to compute the classically forbidden transitions from the target's ground state to fission. In a simple model the energy spectrum and angular distributions of the fragments are calculated for the Coulomb fission in the Xe + U collision. Theoretical predictions are made which may be checked experimentally. (author)
International Nuclear Information System (INIS)
Chudnovsky, D.V.; Chudnovsky, G.V.
1980-01-01
We consider semi-classical approximation to factorized S-matrices. We show that this new class of matrices, called s-matrices, defines Hamiltonian structures for isospectral deformation equations. Concrete examples of factorized s-matrices are constructed and they are used to define Hamiltonian structure for general two-dimensional isospectral deformation systems. (orig.)
The symmetric = ω -semi-classical orthogonal polynomials of class one
Maroni, P.; Mejri, M.
2008-12-01
We give the system of Laguerre-Freud equations associated with the = ω -semi-classical functionals of class one, where = ω is the divided difference operator. This system is solved in the symmetric case. There are essentially two canonical cases. The corresponding integral representations are given.
Semi-classical quantization non-manifestly using the method of harmonic balance
International Nuclear Information System (INIS)
Stepanov, S.S.; Tutik, R.S.; Yaroshenko, A.P.; Schlippe, W. von.
1990-01-01
Based on the ideas of the harmonic balance method and h-expansion a semi-classical procedure for deriving approximations to the energy levels of one-dimensional quantum systems is developed. The procedure is applied to treat the perturbed oscillator potentials. 12 refs.; 2 tabs
Semi-classical calculation of the spin-isospin response functions
International Nuclear Information System (INIS)
Chanfray, G.
1987-03-01
We present a semi-classical calculation of the nuclear response functions beyond the Thomas-Fermi approximation. We apply our formalism to the spin-isospin responses and show that the surface peaked h/2π corrections considerably decrease the ratio longitudinal/transverse as obtained through hadronic probes
Semi-classical scalar propagators in curved backgrounds: formalism and ambiguities
Energy Technology Data Exchange (ETDEWEB)
Grain, J. [Laboratory for Subatomic Physics and Cosmology, Grenoble Universites, CNRS, IN2P3, 53, avenue de Martyrs, 38026 Grenoble cedex (France)]|[AstroParticle and Cosmology, Universite Paris 7, CNRS, IN2P3, 10, rue Alice Domon et Leonie Duquet, 75205 Paris cedex 13 (France); Barrau, A. [Laboratory for Subatomic Physics and Cosmology, Grenoble Universites, CNRS, IN2P3, 53, avenue de Martyrs, 38026 Grenoble cedex (France)
2007-05-15
The phenomenology of quantum systems in curved space-times is among the most fascinating fields of physics, allowing - often at the Gedanken experiment level - constraints on tentative theories of quantum gravity. Determining the dynamics of fields in curved backgrounds remains however a complicated task because of the highly intricate partial differential equations involved, especially when the space metric exhibits no symmetry. In this article, we provide - in a pedagogical way - a general formalism to determine this dynamics at the semi-classical order. To this purpose, a generic expression for the semi-classical propagator is computed and the equation of motion for the probability four-current is derived. Those results underline a direct analogy between the computation of the propagator in general relativistic quantum mechanics and the computation of the propagator for stationary systems in non-relativistic quantum mechanics. (authors)
Semi-classical scalar propagators in curved backgrounds: formalism and ambiguities
International Nuclear Information System (INIS)
Grain, J.; Barrau, A.
2007-05-01
The phenomenology of quantum systems in curved space-times is among the most fascinating fields of physics, allowing - often at the Gedanken experiment level - constraints on tentative theories of quantum gravity. Determining the dynamics of fields in curved backgrounds remains however a complicated task because of the highly intricate partial differential equations involved, especially when the space metric exhibits no symmetry. In this article, we provide - in a pedagogical way - a general formalism to determine this dynamics at the semi-classical order. To this purpose, a generic expression for the semi-classical propagator is computed and the equation of motion for the probability four-current is derived. Those results underline a direct analogy between the computation of the propagator in general relativistic quantum mechanics and the computation of the propagator for stationary systems in non-relativistic quantum mechanics. (authors)
The recurrence coefficients of semi-classical Laguerre polynomials and the fourth Painlevé equation
Filipuk, Galina; Van Assche, Walter; Zhang, Lun
2012-05-01
We show that the coefficients of the three-term recurrence relation for orthogonal polynomials with respect to a semi-classical extension of the Laguerre weight satisfy the fourth Painlevé equation when viewed as functions of one of the parameters in the weight. We compare different approaches to derive this result, namely, the ladder operators approach, the isomonodromy deformations approach and combining the Toda system for the recurrence coefficients with a discrete equation. We also discuss a relation between the recurrence coefficients for the Freud weight and the semi-classical Laguerre weight and show how it arises from the Bäcklund transformation of the fourth Painlevé equation.
The recurrence coefficients of semi-classical Laguerre polynomials and the fourth Painlevé equation
International Nuclear Information System (INIS)
Filipuk, Galina; Van Assche, Walter; Zhang Lun
2012-01-01
We show that the coefficients of the three-term recurrence relation for orthogonal polynomials with respect to a semi-classical extension of the Laguerre weight satisfy the fourth Painlevé equation when viewed as functions of one of the parameters in the weight. We compare different approaches to derive this result, namely, the ladder operators approach, the isomonodromy deformations approach and combining the Toda system for the recurrence coefficients with a discrete equation. We also discuss a relation between the recurrence coefficients for the Freud weight and the semi-classical Laguerre weight and show how it arises from the Bäcklund transformation of the fourth Painlevé equation. (paper)
A study of the relationship between the semi-classical and the generator coordinate methods
International Nuclear Information System (INIS)
Passos, E.J.V. de; Souza Cruz, F.F. de.
Using a very simple type of wave-packet which is obtained by letting unitary displacement operators having as generators canonical operators Q and P in the many-body Hilbert space act on a reference state, the relatinship between the semi-classical and the generator coordinate methods is investigated. The semi-classical method is based on the time-dependent variational principle whereas in the generator coordinate method the wave-packets are taken as generator states. To establish the equivalence of the two-methods, the concept of redundancy of the wave-packet and the importance of the zero-point energy effects are examined in detail, using tools developed in previous works. A numerical application to the case of the Goldhaber-Teller mode in 4 He is made. (Author) [pt
Study between the semi-classical and the generator-coordinate methods
International Nuclear Information System (INIS)
Souza Cruz, F.F. de.
1979-01-01
In this work it is performed a comparison between two microscopic theories of the colective movement: semi-classical theory and the quantum theory from the generator -coordinate method. In boths cases, it is used wave packets |p,q> which depend on two canonical conjugate parameters. These wave packets are constructed by the action of displacement unitory operators, which are generated by canonical operators Q-circumflex and P-circumflex on a referencial state. (A.C.A.S.) [pt
Stochastic semi-classical description of sub-barrier fusion reactions
Directory of Open Access Journals (Sweden)
Ayik Sakir
2011-10-01
Full Text Available A semi-classical method that incorporates the quantum effects of the low-lying vibrational modes is applied to fusion reactions. The quantum effect is simulated by stochastic sampling of initial zero-point ﬂuctuations of the surface modes. In this model, dissipation of the relative energy into non-collective excitations of nuclei can be included straightforwardly. The inclusion of dissipation is shown to increase the agreement with the fusion cross section data of Ni isotopes.
Mathematical properties of a semi-classical signal analysis method: Noisy signal case
Liu, Dayan
2012-08-01
Recently, a new signal analysis method based on a semi-classical approach has been proposed [1]. The main idea in this method is to interpret a signal as a potential of a Schrodinger operator and then to use the discrete spectrum of this operator to analyze the signal. In this paper, we are interested in a mathematical analysis of this method in discrete case considering noisy signals. © 2012 IEEE.
Mathematical properties of a semi-classical signal analysis method: Noisy signal case
Liu, Dayan; Laleg-Kirati, Taous-Meriem
2012-01-01
Recently, a new signal analysis method based on a semi-classical approach has been proposed [1]. The main idea in this method is to interpret a signal as a potential of a Schrodinger operator and then to use the discrete spectrum of this operator to analyze the signal. In this paper, we are interested in a mathematical analysis of this method in discrete case considering noisy signals. © 2012 IEEE.
Semi-classical analysis of scattering of deformed heavy-ions below the Coulomb barrier
International Nuclear Information System (INIS)
Johnson, R.C.; Roberts, E.J.; Sukumar, C.V.; Brink, D.M.
1995-01-01
Polarization observables for the sub-Coulomb elastic scattering of a quadrupole deformed projectile of spin 3/2 from a spinless spherical target are evaluated using a new semi-classical method based on a path-integral formalism. Analytic expressions are obtained which agree well with coupled channels calculations and which predict definite deviations from the ''shape-effect'' relations for tensor analyzing powers
Calculation of the spin-isospin response functions in an extended semi-classical theory
International Nuclear Information System (INIS)
Chanfray, G.
1987-01-01
We present a semi-classical calculation of the spin isospin response-functions beyond Thomas-Fermi theory. We show that surface-peaked ℎ 2 corrections reduce the collective effects predicted by Thomas-Fermi calculations. These effects, small for a volume response, become important for surface responses probed by hadrons. This yields a considerable improvement of the agreement with the (p, p') Los Alamos data
Focal points and the phase of the semi-classical propagator
International Nuclear Information System (INIS)
Levit, S.; Moehring, K.; Smilansky, U.; Dreyfus, T.
1977-01-01
The relation between the phase of the semi-classical propagator and the number of times the classical trajectory is reflected from a caustic is discussed. It is shown that the accepted prescription based on Morse's focal point theorem is valid only for a restricted class of problems (coordinate representation and a positive definite mass tensor). A more general method to evaluate the phase is derived. It applies to all problems of physical interest involving the most general representations (mixed coordinate and momentum) and complicated Hamiltonian functions. The result is of particular relevance for the classical S-matrix. (author)
On the semi-classical limit of scalar products of the XXZ spin chain
Energy Technology Data Exchange (ETDEWEB)
Jiang, Yunfeng; Brunekreef, Joren [Institut für Theoretische Physik, ETH Zürich,Wolfgang Pauli Strasse 27, CH-8093 Zürich (Switzerland)
2017-03-03
We study the scalar products between Bethe states in the XXZ spin chain with anisotropy |Δ|>1 in the semi-classical limit where the length of the spin chain and the number of magnons tend to infinity with their ratio kept finite and fixed. Our method is a natural yet non-trivial generalization of similar methods developed for the XXX spin chain. The final result can be written in a compact form as a contour integral in terms of Faddeev’s quantum dilogarithm function, which in the isotropic limit reduces to the classical dilogarithm function.
On the semi-classical limit of scalar products of the XXZ spin chain
International Nuclear Information System (INIS)
Jiang, Yunfeng; Brunekreef, Joren
2017-01-01
We study the scalar products between Bethe states in the XXZ spin chain with anisotropy |Δ|>1 in the semi-classical limit where the length of the spin chain and the number of magnons tend to infinity with their ratio kept finite and fixed. Our method is a natural yet non-trivial generalization of similar methods developed for the XXX spin chain. The final result can be written in a compact form as a contour integral in terms of Faddeev’s quantum dilogarithm function, which in the isotropic limit reduces to the classical dilogarithm function.
Regular black holes from semi-classical down to Planckian size
Spallucci, Euro; Smailagic, Anais
In this paper, we review various models of curvature singularity free black holes (BHs). In the first part of the review, we describe semi-classical solutions of the Einstein equations which, however, contains a “quantum” input through the matter source. We start by reviewing the early model by Bardeen where the metric is regularized by-hand through a short-distance cutoff, which is justified in terms of nonlinear electro-dynamical effects. This toy-model is useful to point-out the common features shared by all regular semi-classical black holes. Then, we solve Einstein equations with a Gaussian source encoding the quantum spread of an elementary particle. We identify, the a priori arbitrary, Gaussian width with the Compton wavelength of the quantum particle. This Compton-Gauss model leads to the estimate of a terminal density that a gravitationally collapsed object can achieve. We identify this density to be the Planck density, and reformulate the Gaussian model assuming this as its peak density. All these models, are physically reliable as long as the BH mass is big enough with respect to the Planck mass. In the truly Planckian regime, the semi-classical approximation breaks down. In this case, a fully quantum BH description is needed. In the last part of this paper, we propose a nongeometrical quantum model of Planckian BHs implementing the Holographic Principle and realizing the “classicalization” scenario recently introduced by Dvali and collaborators. The classical relation between the mass and radius of the BH emerges only in the classical limit, far away from the Planck scale.
Dirac particle in a plane wave field and the semi-classical approximation
Energy Technology Data Exchange (ETDEWEB)
Bourouaine, S. [Department of Physics, Faculty of Sciences, Mentouri University, Constantine (Algeria)
2005-04-01
In this paper we investigate the influence of photon represented by plane wave field on Dirac particle in the context of path integral approach given by Fradkin and Gitman formalism. In our case, although the action relative to Dirac particle in plane wave field seems to be non quadratic, the result obtained by semi-classical approach is the same as that found by an exact calculation. Hence; when we add the plane wave field to any quadratic actions related to Fradkin and Gitman approach, the total action behaves like quadratic. (Abstract Copyright [2005], Wiley Periodicals, Inc.)
Dirac particle in a plane wave field and the semi-classical approximation
International Nuclear Information System (INIS)
Bourouaine, S.
2005-01-01
In this paper we investigate the influence of photon represented by plane wave field on Dirac particle in the context of path integral approach given by Fradkin and Gitman formalism. In our case, although the action relative to Dirac particle in plane wave field seems to be non quadratic, the result obtained by semi-classical approach is the same as that found by an exact calculation. Hence; when we add the plane wave field to any quadratic actions related to Fradkin and Gitman approach, the total action behaves like quadratic. (Abstract Copyright [2005], Wiley Periodicals, Inc.)
Barghouty, A. F.
2014-01-01
Accurate estimates of electroncapture cross sections at energies relevant to the modeling of the transport, acceleration, and interaction of energetic neutral atoms (ENA) in space (approximately few MeV per nucleon) and especially for multi-electron ions must rely on detailed, but computationally expensive, quantum-mechanical description of the collision process. Kuang's semi-classical approach is an elegant and efficient way to arrive at these estimates. Motivated by ENA modeling efforts for apace applications, we shall briefly present this approach along with sample applications and report on current progress.
Semi-classical derivation of charge-quantization through charge-field self-interaction
International Nuclear Information System (INIS)
Kosok, M.; Madhyastha, V.L.
1990-01-01
A semi-classical synthesis of classical mechanics, wave mechanics, and special relativity yields a unique nonlinear energy-wave structure of relations (velocity triad uv = c 2 ) fundamental to modern physics. Through the above vehicle, using Maxwell's equations, charge quantization and the fine structure constant are derived. It is shown that the numerical value of the nonlinear charge-field self-interaction range for the electron is of the order of 10 -13 m, which is greater than the classical electron radius but less than the Compton wavelength of the electron. Finally, it is suggested that the structure of the electron-in-space is expressed by a self-extending nonlinear ''fractal geometry'' based on derived numerical values obtained from our model, thus opening this presentation of charge-field structure to experimental testing for possible verification
Semi-classical approaches to the phase space evolutions in intermediate energy heavy ion collisions
Energy Technology Data Exchange (ETDEWEB)
Remaud, B; Sebille, F; Raffray, Y; Gregoire, C; Vinet, L
1986-01-06
The properties of semi-classical phase space evolution equations - as the Vlasov/Boltzmann equations - are discussed in the context of the heavy ion reaction theory at intermediate energies (from 10 to 100 MeV per nucleon). The generalized coherent state set is shown to form a (over) complete basis for the phase space; then every solution of the Vlasov/Boltzmann equations can be defined as a convolution product of the generalized coherent state basis by an appropriate weight function w. The uniform approximation for w is shown to provide an accurate semi-classical description of fermion systems in their ground state: the examples of fermions in a harmonic well and of cold nuclei are discussed. The solution of the Vlasov equation amounts to follow the time evolution of the coherent states which play the role of a moving basis. For the Boltzmann equation, the collision term is taken into account by explicit or implicit variations of the function w. Typical applications are discussed: nuclear response to the giant monopole resonance excitation, fast nucleon emission in heavy-ion reactions. (orig.).
A semi-classical treatment of dissipative processes based on Feynman's influence functional method
International Nuclear Information System (INIS)
Moehring, K.; Smilansky, U.
1980-01-01
We develop a semi-classical treatment of dissipative processes based on Feynman's influence functional method. Applying it to deep inelastic collisions of heavy ions we study inclusive transition probabilities corresponding to a situation when only a set of collective variables is specified in the initial and final states. We show that the inclusive probabilities as well as the final energy distributions can be expressed in terms of properly defined classical paths and their corresponding stability fields. We present a uniform approximation for the study of quantal interference and focussing phenomena and discuss the conditions under which they are to be expected. For the dissipation mechanism we study three approximations - the harmonic model for the internal system, the weak coupling (diabatic) and the adiabatic coupling. We show that these three limits can be treated in the same manner. We finally compare the present formalism with other methodes as were introduced for the description of dissipation in deep inelastic collisions. (orig.)
Spectral data de-noising using semi-classical signal analysis: application to localized MRS
Laleg-Kirati, Taous-Meriem
2016-09-05
In this paper, we propose a new post-processing technique called semi-classical signal analysis (SCSA) for MRS data de-noising. Similar to Fourier transformation, SCSA decomposes the input real positive MR spectrum into a set of linear combinations of squared eigenfunctions equivalently represented by localized functions with shape derived from the potential function of the Schrodinger operator. In this manner, the MRS spectral peaks represented as a sum of these \\'shaped like\\' functions are efficiently separated from noise and accurately analyzed. The performance of the method is tested by analyzing simulated and real MRS data. The results obtained demonstrate that the SCSA method is highly efficient in localized MRS data de-noising and allows for an accurate data quantification.
Spectral data de-noising using semi-classical signal analysis: application to localized MRS
Laleg-Kirati, Taous-Meriem; Zhang, Jiayu; Achten, Eric; Serrai, Hacene
2016-01-01
In this paper, we propose a new post-processing technique called semi-classical signal analysis (SCSA) for MRS data de-noising. Similar to Fourier transformation, SCSA decomposes the input real positive MR spectrum into a set of linear combinations of squared eigenfunctions equivalently represented by localized functions with shape derived from the potential function of the Schrodinger operator. In this manner, the MRS spectral peaks represented as a sum of these 'shaped like' functions are efficiently separated from noise and accurately analyzed. The performance of the method is tested by analyzing simulated and real MRS data. The results obtained demonstrate that the SCSA method is highly efficient in localized MRS data de-noising and allows for an accurate data quantification.
A qualitative semi-classical treatment of an isolated semi-polar quantum dot
International Nuclear Information System (INIS)
Young, Toby D
2011-01-01
To qualitatively determine the behaviour of micro-macro properties of a quantum dot grown in a non-polar direction, we propose a simple semi-classical model based on well established ideas. We take into account the following empirical phenomena: (i) The displacement and induced strain at heterojunctions; (ii) The electrostatic potential arising from piezoelectric and spontaneous polarisation; and (iii) The localisation of excitons (particle-hole pairs) arising from quantum confinement. After some algebraic manipulation used to cast the formalism into an arbitrarily rotated frame, a numerical model is developed for the case of a semi-polar wurtzite GaN quantum dot buried in a wurtzite AlN matrix. This scheme is found to provide a satisfying qualitative description of an isolated semi-polar quantum dot in a way that is accessible to further physical interpretation and quantification.
Semi-classical description of Rydberg atoms in strong, single-cycle electromagnetic pulses
International Nuclear Information System (INIS)
Jensen, R.V.; Sanders, M.M.
1993-01-01
Recent experimental measurements of the excitation and ionization of Rydberg atoms by single-cycle, electromagnetic pulses have revealed a variety of novel features. Because many quantum states are strongly coupled by the broadband radiation in the short pulse, the traditional methods of quantum mechanics are inadequate to account for the experimental results. We have therefore developed a semi-classical description of the interaction of both hydrogenic and non-hydrogenic atoms with single-cycle pulses of intense, electromagnetic radiation which is based on the strong correspondence theory of Percival and Richards. This theory, which was originally introduced for the description of strong atomic collisions, accounts for some of the surprising features of the experimental measurements and provides new predictions for future experimental studies
Calculation of the level density parameter using semi-classical approach
International Nuclear Information System (INIS)
Canbula, B.; Babacan, H.
2011-01-01
The level density parameters (level density parameter a and energy shift δ) for back-shifted Fermi gas model have been determined for 1136 nuclei for which complete level scheme is available. Level density parameter is calculated by using the semi-classical single particle level density, which can be obtained analytically through spherical harmonic oscillator potential. This method also enables us to analyze the Coulomb potential's effect on the level density parameter. The dependence of this parameter on energy has been also investigated. Another parameter, δ, is determined by fitting of the experimental level scheme and the average resonance spacings for 289 nuclei. Only level scheme is used for optimization procedure for remaining 847 nuclei. Level densities for some nuclei have been calculated by using these parameter values. Obtained results have been compared with the experimental level scheme and the resonance spacing data.
Semi-classical approaches for the proton emission in intermediate energy heavy ion reactions
International Nuclear Information System (INIS)
Gregoire, C.; Scheuter, F.; Remaud, B.; Sebille, F.
1984-05-01
Semi-classical approaches are proposed to study the transition between the one- and two-body processes in intermediate energy heavy ion collisions. The Landau-Vlasov equation is used as a transport equation for nucleons in the nuclear matter. We apply our formalism to the fast proton ejection. On the one hand, the effects of the nucleon-nucleon collisions are studied for the particles which travel through the nucleus cores. On the other hand, the inertial emission turns out to be an important proton emission mechanism. Our results conflict the interpretation of the proton spectra in terms of moving sources. Reasonable agreements with the experimental data are found without reference to any thermal equilibrium
Classical and semi-classical treatments of Li3+, Ne10++H(1s) collisions
International Nuclear Information System (INIS)
Errea, L F; Illescas, Clara; Mendez, L; Pons, B; Riera, A; Suarez, J
2004-01-01
We perform molecular close-coupling and impact-parameter classical trajectory Monte Carlo calculations of total and partial cross sections for capture and ionization in collisions of highly charged ions on H(1s). We first consider Li 3+ +H(1s) as a benchmark to ascertain the complementarity of the methods, and then Ne 10+ +H(1s), which has been scarcely studied up to now, and has recently become of interest for fusion plasma research
International Nuclear Information System (INIS)
Lusanna, Luca
2004-01-01
The four (electro-magnetic, weak, strong and gravitational) interactions are described by singular Lagrangians and by Dirac-Bergmann theory of Hamiltonian constraints. As a consequence a subset of the original configuration variables are gauge variables, not determined by the equations of motion. Only at the Hamiltonian level it is possible to separate the gauge variables from the deterministic physical degrees of freedom, the Dirac observables, and to formulate a well posed Cauchy problem for them both in special and general relativity. Then the requirement of causality dictates the choice of retarded solutions at the classical level. However both the problems of the classical theory of the electron, leading to the choice of (1/2) (retarded + advanced) solutions, and the regularization of quantum field theory, leading to the Feynman propagator, introduce anticipatory aspects. The determination of the relativistic Darwin potential as a semi-classical approximation to the Lienard-Wiechert solution for particles with Grassmann-valued electric charges, regularizing the Coulomb self-energies, shows that these anticipatory effects live beyond the semi-classical approximation (tree level) under the form of radiative corrections, at least for the electro-magnetic interaction.Talk and 'best contribution' at The Sixth International Conference on Computing Anticipatory Systems CASYS'03, Liege August 11-16, 2003
International Nuclear Information System (INIS)
Gosson, Maurice A de
2008-01-01
The nearby orbit method is a powerful tool for constructing semi-classical solutions of Schroedinger's equation when the initial datum is a coherent state. In this paper, we first extend this method to arbitrary squeezed states and thereafter apply our results to the Schroedinger equation in phase space. This adaptation requires the phase-space Weyl calculus developed in previous work of ours. We also study the regularity of the semi-classical solutions from the point of view of the Feichtinger algebra familiar from the theory of modulation spaces
Semi-classical description of matter wave interferometers and hybrid quantum systems
Energy Technology Data Exchange (ETDEWEB)
Schneider, Mathias
2015-02-16
This work considers the semi-classical description of two applications involving cold atoms. This is, on one hand, the behavior of a BOSE-EINSTEIN condensate in hybrid systems, i.e. in contact with a microscopic object (carbon nanotubes, fullerenes, etc.). On the other, the evolution of phase space distributions in matter wave interferometers utilizing ray tracing methods was discussed. For describing condensates in hybrid systems, one can map the GROSS-PITAEVSKII equation, a differential equation in the complex-valued macroscopic wave function, onto a system of two differential equations in density and phase. Neglecting quantum dispersion, one obtains a semiclassical description which is easily modified to incorporate interactions between condensate and microscopical object. In our model, these interactions comprise attractive forces (CASIMIR-POLDER forces) and loss of condensed atoms due to inelastic collisions at the surface of the object. Our model exhibited the excitation of sound waves that are triggered by the object's rapid immersion, and spread across the condensate thereafter. Moreover, local particle loss leads to a shrinking of the bulk condensate. We showed that the total number of condensed particles is decreasing potentially in the beginning (large condensate, strong mean field interaction), while it decays exponentially in the long-time limit (small condensate, mean field inetraction negligible). For representing the physics of matter wave interferometers in phase space, we utilized the WIGNER function. In semi-classical approximation, which again consists in ignoring the quantum dispersion, this representation is subject to the same equation of motion as classical phase space distributions, i.e. the LIOUVILLE equation. This implies that time evolution of theWIGNER function follows a phase space flow that consists of classical trajectories (classical transport). This means, for calculating a time-evolved distribution, one has know the initial
Holographic description of 2D conformal block in semi-classical limit
Energy Technology Data Exchange (ETDEWEB)
Chen, Bin [Department of Physics and State Key Laboratory of Nuclear Physics and Technology,Peking University, 5 Yiheyuan Rd, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter,5 Yiheyuan Rd, Beijing 100871 (China); Center for High Energy Physics, Peking University, 5 Yiheyuan Rd, Beijing 100871 (China); Wu, Jie-qiang [Department of Physics and State Key Laboratory of Nuclear Physics and Technology,Peking University, 5 Yiheyuan Rd, Beijing 100871 (China); Zhang, Jia-ju [Theoretical Physics Division, Institute of High Energy Physics,Chinese Academy of Sciences, 19B Yuquan Rd, Beijing 100049 (China); Theoretical Physics Center for Science Facilities, Chinese Academy of Sciences,19B Yuquan Rd, Beijing 100049 (China)
2016-10-20
In this paper, we study the holographic descriptions of the conformal block of heavy operators in two-dimensional large c conformal field theory. We consider the case that the operators are pairwise inserted such that the distance between the operators in a pair is much smaller than the others. In this case, each pair of heavy operators creates a conical defect in the bulk. We propose that the conformal block is dual to the on-shell action of three dimensional geometry with conical defects in the semi-classical limit. We show that the variation of the on-shell action with respect to the conical angle is equal to the length of the corresponding conical defect. We derive this differential relation on the conformal block in the field theory by introducing two extra light operators as both the probe and the perturbation. Our study also suggests that the area law of the holographic Rényi entropy must holds for a large class of states generated by a finite number of heavy operators insertion.
Thermoelectric properties of fully hydrogenated graphene: Semi-classical Boltzmann theory
International Nuclear Information System (INIS)
Reshak, A. H.
2015-01-01
Based on the calculated band structure, the electronic transport coefficients of chair-/boat-like graphane were evaluated by using the semi-classical Boltzmann theory and rigid band model. The maximum value of electrical conductivity for chair (boat)-like graphane of about 1.4 (0.6) × 10 19 (Ωms) −1 is achieved at 600 K. The charge carrier concentration and the electrical conductivity linearly increase with increasing the temperature in agreement with the experimental work for graphene. The investigated materials exhibit the highest value of Seebeck coefficient at 300 K. We should emphasize that in the chemical potential between ∓0.125 μ(eV) the investigated materials exhibit minimum value of electronic thermal conductivity, therefore, maximum efficiency. As the temperature increases, the electronic thermal conductivity increases exponentially, in agreement with the experimental data of graphene. We also calculated the power factor of chair-/boat-like graphane at 300 and 600 K as a function of chemical potential between ∓0.25 μ(eV)
Coherent state methods for semi-classical heavy-ion physics
International Nuclear Information System (INIS)
Remaud, B.; Sebille, F.; Raffray, Y.
1985-01-01
A semi-classical model of many fermion systems is developed in view of solving the Vlasov equation; it provides an unified description of both static and dynamic properties of the system. The phase space distribution functions are written as convolution products of generalized coherent state distributions with semi-probabilistic weight functions. The generalized coherent states are defined from the local constants of motion of the dynamical system; they may reduce to the usuel ones (eigen states of the annihilation operator) only at the harmonic limit. Solving the Vlasov equation consists in two steps: (i) search for weight functions which properly describe the initial density distributions (ii) calculation of the evolutions of the coherent state set which acts as a moving basis for the Vlasov equation solutions. Sample applications to statics are analyzed: fermions in a harmonic field, self-consistent nuclear slabs. Outlooks of dynamical applications are discussed with a special attention to the fast nucleon emission in heavy-ion reactions
Semi-classical approach of heavy ion physics at intermediate energies
International Nuclear Information System (INIS)
Vinet, L.
1986-01-01
The study of heavy ion collisions at intermediate energies (10 to 100 MeV/A), can be undertaken by a semi-classical approach: the nuclear Vlasov equation. It is possible to decompose the one body distribution function over a suitable coherent state basis for dynamical studies. This method is applied for colliding slabs, and the results are compared with those of TDHF. With imposed spherical symmetry, the isoscalar monopole resonance, evaporation, formation of bubble nuclei and total evaporation, are obtained. The extension to three dimensions and to the Landau-Vlasov equation through the residual interaction included in the Uehling-Uhlenbeck collision term, permits a general study of the dynamical instability of highly excited nuclei. The application to heavy ion collisions gives a description of both the main mechanisms of reaction, and the ineffective fusion for the system 40 Ar (35 MeV/A) + 27 Al. Alpha particle multiplicities in correlation with evaporated residues in the experience 40 Ar (27 MeV/A) + 27 Al, have been extracted. From theoretical results, different scenari are proposed (entrance channel limitation and exit channel disintegration), in order to explain the disappearance of the fusion component observed for this system at energies above 32 MeV/A [fr
Hounga, C.; Hounkonnou, M. N.; Ronveaux, A.
2006-10-01
In this paper, we give Laguerre-Freud equations for the recurrence coefficients of discrete semi-classical orthogonal polynomials of class two, when the polynomials in the Pearson equation are of the same degree. The case of generalized Charlier polynomials is also presented.
Semi-classical precompound decay models for heavy ion reactions of 10-100 MeV/nucleon
International Nuclear Information System (INIS)
Blann, M.
1986-01-01
The hybrid and Boltzmann master equation, which predict heavy ion precompound decay phenomena, are investigated. These are both semi-classical approaches. The physical concepts of these two models are discussed, and their numerical formulations are summarized. Their success in reproducing experimentally measured (HI,n) spectra and in estimating limits on beam momentum transfer due to the precompound nucleon emission cascade are summarized. Results of calculations for subthreshold pion production are presented and compared with experimental yields. 19 refs., 5 figs
International Nuclear Information System (INIS)
Angeli, Istvan
1990-01-01
The dependence of total neutron cross section on mass number can be calculated by the black nucleus formula, according to the optical model. The fine structure of mass number dependence is studied, and a correction factor formula is given on the basis of a semi-classical optical model. Yielding results in good agreement with experimental data. In addition to the mass number dependence, the neutron-energy dependence can also be calculated using this model. (K.A.)
International Nuclear Information System (INIS)
Akhiezer, A.I.; Shul'ga, N.F.
1991-01-01
The process of relativistic particle radiation in an external field has been studied in the semi-classical approximation rather extensively. The main problem arising in the studies is in expressing the formula of the quantum theory of radiation in terms of classical quantities, for example of the classical trajectories. However, it still remains unclear how the particle trajectory is assigned, that is which particular initial or boundary conditions determine the trajectory in semi-classical approximation quantum theory of radiation. We shall try to solve this problem. Its importance comes from the fact that in some cases one and the same boundary conditions may give rise to two or more trajectories. We demonstrate that this fact must necessarily be taken into account on deriving the classical limit for the formulae of the quantum theory of radiation, since it leads to a specific interference effect in radiation. The method we used to deal with the problem is similar to the method employed by Fock to analyze the problem of a canonical transformation in classical and quantum mechanics. (author)
Geneste, Grégory; Hermet, Jessica; Dezanneau, Guilhem
2017-08-09
We respond to the erroneous criticisms about our modeling of proton transport in barium stannate [G. Geneste et al., Phys. Chem. Chem. Phys., 2015, 17, 19104]. In this previous work, we described, on the basis of density-functional calculations, proton transport in the classical and semi-classical regimes, and provided arguments in favor of an adiabatic picture for proton transfer at low temperature. We re-explain here our article (with more detail and precision), the content of which has been distorted in the Comment, and reiterate our arguments in this reply. We refute all criticisms. They are completely wrong in the context of our article. Even though a few of them are based on considerations probably true in some metals, they make no sense here since they do not correspond to the content of our work. It has not been understood in the Comment that two competitive configurations, associated with radically different transfer mechanisms, have been studied in our work. It has also not been understood in the Comment that the adiabatic regime described for transfer occurs in the protonic ground state, in a very-low barrier configuration with the protonic ground state energy larger than the barrier. Serious confusion has been made in the Comment with the case of H in metals like Nb or Ta, leading to the introduction of the notion of (protonic) "excited-state proton transfer", relevant for H in some metals, but (i) that does not correspond to the (ground state) adiabatic transfers here described, and (ii) that does not correspond to what is commonly described as the "adiabatic limit for proton transfer" in the scientific literature. We emphasize, accordingly, the large differences between proton transfer in the present oxide and hydrogen jumps in metals like Nb or Ta, and the similarities between proton transfer in the present oxide and in acid-base solutions. We finally describe a scenario for proton transfer in the present oxide regardless of the temperature regime.
International Nuclear Information System (INIS)
Chen Changxin; Zhang Wei; Zhao Bo; Zhang Yafei
2009-01-01
An efficient semi-classical numerical modeling approach has been developed to simulate the coaxial Schottky-barrier carbon nanotube field-effect transistor (SB-CNTFET). In the modeling, the electrostatic potential of the CNT is obtained by self-consistently solving the analytic expression of CNT carrier distribution and the cylindrical Poisson equation, which significantly enhances the computational efficiency and simultaneously present a result in good agreement to that obtained from the non-equilibrium Green's function (NEGF) formalism based on the first principle. With this method, the effects of the CNT diameter, power supply voltage, thickness and dielectric constant of gate insulator on the device performance are investigated.
International Nuclear Information System (INIS)
Guinet, M.; Rohart, F.; Buldyreva, J.; Gupta, V.; Eliet, S.; Motiyenko, R.A.; Margulès, L.; Cuisset, A.; Hindle, F.; Mouret, G.
2012-01-01
Room-temperature N 2 -broadening coefficients of methyl chloride rotational lines are measured over a large interval of quantum numbers (6≤J≤50, 0≤K≤18) by a submillimeter frequency-multiplication chain (J≤31) and a terahertz photomixing continuous-wave spectrometer (J≥31). In order to check the accuracy of both techniques, the measurements of identical lines are compared for J=31. The pressure broadening coefficients are deduced from line fits using mainly a Voigt profile model. The excellent signal-to-noise ratio of the frequency-multiplication scheme highlights some speed dependence effect on the line shape. Theoretical values of these coefficients are calculated by a semi-classical approach with exact trajectories. An intermolecular potential including atom-atom interactions is used for the first time. It is shown that, contrary to the previous theoretical predictions, the contributions of short-range forces are important for all values of the rotational quantum numbers. Additional testing of modifications required in the semi-classical formalism for a correct application of the cumulant expansion is also performed. It is stated that the use of the cumulant average on the rotational states of the perturbing molecule leads, for high J and small K values, to slightly higher line-broadening coefficients, as expected for the relatively strong interacting CH 3 Cl-N 2 system. The excellent agreement between the theoretical and the experimental results ensures the reliability of these data.
Guinet, M.; Rohart, F.; Buldyreva, J.; Gupta, V.; Eliet, S.; Motiyenko, R. A.; Margulès, L.; Cuisset, A.; Hindle, F.; Mouret, G.
2012-07-01
Room-temperature N2-broadening coefficients of methyl chloride rotational lines are measured over a large interval of quantum numbers (6≤J≤50, 0≤K≤18) by a submillimeter frequency-multiplication chain (J≤31) and a terahertz photomixing continuous-wave spectrometer (J≥31). In order to check the accuracy of both techniques, the measurements of identical lines are compared for J=31. The pressure broadening coefficients are deduced from line fits using mainly a Voigt profile model. The excellent signal-to-noise ratio of the frequency-multiplication scheme highlights some speed dependence effect on the line shape. Theoretical values of these coefficients are calculated by a semi-classical approach with exact trajectories. An intermolecular potential including atom-atom interactions is used for the first time. It is shown that, contrary to the previous theoretical predictions, the contributions of short-range forces are important for all values of the rotational quantum numbers. Additional testing of modifications required in the semi-classical formalism for a correct application of the cumulant expansion is also performed. It is stated that the use of the cumulant average on the rotational states of the perturbing molecule leads, for high J and small K values, to slightly higher line-broadening coefficients, as expected for the relatively strong interacting CH3Cl-N2 system. The excellent agreement between the theoretical and the experimental results ensures the reliability of these data.
Semi-classical noise investigation for sub-40nm metal-oxide-semiconductor field-effect transistors
International Nuclear Information System (INIS)
Spathis, C.; Birbas, A.; Georgakopoulou, K.
2015-01-01
Device white noise levels in short channel Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) dictate the performance and reliability of high-frequency circuits ranging from high-speed microprocessors to Low-Noise Amplifiers (LNAs) and microwave circuits. Recent experimental noise measurements with very short devices demonstrate the existence of suppressed shot noise, contrary to the predictions of classical channel thermal noise models. In this work we show that, as the dimensions continue to shrink, shot noise has to be considered when the channel resistance becomes comparable to the barrier resistance at the source-channel junction. By adopting a semi-classical approach and taking retrospectively into account transport, short-channel and quantum effects, we investigate the partitioning between shot and thermal noise, and formulate a predictive model that describes the noise characteristics of modern devices
Semi-classical noise investigation for sub-40nm metal-oxide-semiconductor field-effect transistors
Energy Technology Data Exchange (ETDEWEB)
Spathis, C., E-mail: cspathis@ece.upatras.gr; Birbas, A.; Georgakopoulou, K. [Department of Electrical and Computer Engineering, University of Patras, Patras 26500 (Greece)
2015-08-15
Device white noise levels in short channel Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) dictate the performance and reliability of high-frequency circuits ranging from high-speed microprocessors to Low-Noise Amplifiers (LNAs) and microwave circuits. Recent experimental noise measurements with very short devices demonstrate the existence of suppressed shot noise, contrary to the predictions of classical channel thermal noise models. In this work we show that, as the dimensions continue to shrink, shot noise has to be considered when the channel resistance becomes comparable to the barrier resistance at the source-channel junction. By adopting a semi-classical approach and taking retrospectively into account transport, short-channel and quantum effects, we investigate the partitioning between shot and thermal noise, and formulate a predictive model that describes the noise characteristics of modern devices.
Semi-classical estimation of ground state energies on a sphere
International Nuclear Information System (INIS)
Sollie, R.
1989-01-01
It is considered electrons confined to the surface of a sphere, and calculate the classical electrostatic energies for up to 32 electrons. It is introduced a magnetic field perpendicular to the surface of the sphere, by placing a magnetic monopole at the origin. The classical analysis can be extended by replacing the pair-potential by an effective potential, defined as the quantum mechanical energy of a pair of electrons at the appropriate distance. (A.C.A.S.) [pt
International Nuclear Information System (INIS)
Zhang Jingshang
1990-04-01
A semi-classical model of multi-step direct and compound nuclear reactions has been proposed to describe the angular distributions of light particles emitted in reaction processes induced by nucleons with energies of several tens of MeV. The exact closed solution for the time-dependent master equation of the exciton model is applied. Based on the Fermi gas model, the scattering kernel for two-nucleon collisions includes the influence of the Fermi motion and the Pauli exclusion principle, which give a significant improvement in the description of the rise of the backward distributions. The angle-energy correlation for the first few steps of the collision process (multi-step direct process) yields further improvements in the description of the angular distribution. The pick-up mechanism is employed to describe the composite particle emission. This reasonable physical picture reproduces the experimental data of the energy spectra of composite particles satisfactorily. The angular distribution of the emitted composite particles is determined by an angular factor in terms of the momentum conservation of the nucleons forming the composite cluster. The generalized master equation is employed for the multi-step compound process. Thus a classical approach has been established to calculate the double differential cross sections for all kinds of particles emitted in multi-step nuclear reaction processes. (author). 19 refs, 6 figs, 1 tab
Energy Technology Data Exchange (ETDEWEB)
Niquet, Yann-Michel, E-mail: yniquet@cea.fr; Nguyen, Viet-Hung; Duchemin, Ivan [L-Sim, SP2M, UMR-E CEA/UJF-Grenoble 1, INAC, Grenoble (France); Triozon, François [CEA, LETI-MINATEC, Grenoble (France); Nier, Olivier; Rideau, Denis [ST Microelectronics, Crolles (France)
2014-02-07
We discuss carrier mobilities in the quantum Non-Equilibrium Green's Functions (NEGF) framework. We introduce a method for the extraction of the mobility that is free from contact resistance contamination and with minimal needs for ensemble averages. We focus on silicon thin films as an illustration, although the method can be applied to various materials such as semiconductor nanowires or carbon nanostructures. We then introduce a new paradigm for the definition of the partial mobility μ{sub M} associated with a given elastic scattering mechanism “M,” taking phonons (PH) as a reference (μ{sub M}{sup −1}=μ{sub PH+M}{sup −1}−μ{sub PH}{sup −1}). We argue that this definition makes better sense in a quantum transport framework as it is free from long range interference effects that can appear in purely ballistic calculations. As a matter of fact, these mobilities satisfy Matthiessen's rule for three mechanisms [e.g., surface roughness (SR), remote Coulomb scattering (RCS) and phonons] much better than the usual, single mechanism calculations. We also discuss the problems raised by the long range spatial correlations in the RCS disorder. Finally, we compare semi-classical Kubo-Greenwood (KG) and quantum NEGF calculations. We show that KG and NEGF are in reasonable agreement for phonon and RCS, yet not for SR. We discuss the reasons for these discrepancies.
Energy Technology Data Exchange (ETDEWEB)
Benhassine, B. [Nantes Univ., 44 (France)
1994-01-14
At intermediate energies the heavy ion collisions can be studied within the framework of a semi-classical approach based on the Vlasov-Uehling-Uhlenbeck (VUU) equation. Such an approach reduces the N-body problem to its description in terms of the one-body distribution function and constitutes the basis of several successful simulation models. Our aim in this work is to extend these average approaches to treat fluctuations. Within the framework of a linear approximation, we derived a Fokker-Planck transport equation in the one-body phase space. When it is reduced to its first moments, one recovers the VUU equation for the average dynamics together with the time evolution equation for the correlations. The collective transport coefficients are then obtained by projection on the one-body collective space. Independently, using a projection method introduced by Van Kampen, based on the constants of motion, we deduce the stationary expressions for the covariance matrix in phase space. We extract then, the equilibrium dispersions of one-body observables in a homogeneous case and in a spherical symmetric one. These results are compared with two types of simulation models in a relaxation time approximation. In the first one which is of Lagrangian type, the collective transport coefficients are directly extracted from the simulation and consequently the numerical fluctuations are washed out. The second model, due to its Eulerian character, allows us to make a microscopical comparison. (author) 58 refs.
International Nuclear Information System (INIS)
Pollock, M.D.
1988-01-01
In quantum cosmology, a wave function Ψ for a given theory can be obtained by solving the Wheeler-DeWitt equation, using the semi-classical approximation to the path integral over euclidean metrics to impose the boundary condition, as described by Hawking and his collaborators. If the universe is expanding as a quasi-de Sitter space-time, then it is possible to derive a Fokker-Planck equation for the probability distribution P, as shown by Starobinsky. Arguing by analogy with quantum mechanics in flat space-time, one would expect that P ∝ ΨΨ * . We examine this assertion by reference to the scale-invariant theory L = -1/24 βR 2 , whose wave function has been calculated in mini-superspace by Horowitz, and whose classical solutions are de Sitter space-times. It appears that deviations from the relation P ∝ ΨΨ * are attributable to long-wavelength fluctuations δΦ e ≅ H/2π in the effective inflaton field Φ c =√(βR)=√(12β) H. Their existence is taken into account in the derivation of the Fokker-Planck equation, but not in the derivation of Ψ when this is restricted to mini-superspace. In the limit β → ∞, we find that δΦ e /Φ c → 0 and that P ∝ ΨΨ * . The scale-invariant theory L = (1/2εφ 2 R-1/4λΦ 4 ) can be similarly analyzed. Inclusion of a kinetic term 1/2Φ; k Φ ;k destroys this similarity, which is restored however upon addition of a term (-1/24βR 2 ). (orig.)
Louarn, K.; Claveau, Y.; Hapiuk, D.; Fontaine, C.; Arnoult, A.; Taliercio, T.; Licitra, C.; Piquemal, F.; Bounouh, A.; Cavassilas, N.; Almuneau, G.
2017-09-01
The aim of this study is to investigate the impact of multiband corrections on the current density in GaAs tunnel junctions (TJs) calculated with a refined yet simple semi-classical interband tunneling model (SCITM). The non-parabolicity of the considered bands and the spin-orbit effects are considered by using a recently revisited SCITM available in the literature. The model is confronted to experimental results from a series of molecular beam epitaxy grown GaAs TJs and to numerical results obtained with a full quantum model based on the non-equilibrium Green’s function formalism and a 6-band k.p Hamiltonian. We emphasize the importance of considering the non-parabolicity of the conduction band by two different measurements of the energy-dependent electron effective mass in N-doped GaAs. We also propose an innovative method to compute the non-uniform electric field in the TJ for the SCITM simulations, which is of prime importance for a successful operation of the model. We demonstrate that, when considering the multiband corrections and this new computation of the non-uniform electric field, the SCITM succeeds in predicting the electrical characteristics of GaAs TJs, and are also in agreement with the quantum model. Besides the fundamental study of the tunneling phenomenon in TJs, the main benefit of this SCITM is that it can be easily embedded into drift-diffusion software, which are the most widely-used simulation tools for electronic and opto-electronic devices such as multi-junction solar cells, tunnel field-effect transistors, or vertical-cavity surface-emitting lasers.
International Nuclear Information System (INIS)
Sen, A.K.; Bhattacharya, S.
2006-12-01
In this paper, we study the variation of low temperature (T) dc conductance, G(T), of a semi-classical percolative Random Resistor cum Tunneling-bond Network (RRTN), in the presence of a linearly temperature-dependent microscopic voltage threshold, υ g (T). This model (proposed by our group in the early 90's) considers a phenomenological semi-classical tunneling (or, hopping through a barrier) process. Just as in our previous constant-υ g case, we find in the present study also that the variable range hopping (VRH) exponent γ varies continuously with the ohmic concentration p in a non-monotonic fashion. In addition, we observe a new shoulder-like behaviour of G(T) in the intermediate temperature range, below the conductance maximum. (author)
International Nuclear Information System (INIS)
Kaczmarczyk, Maria
2005-01-01
The results of calculations of level densities ρ, in the vicinity of the neutron binding energy S n , are presented. These results were obtained using the Boehning combinatorial method for the calculation of particle-hole state densities dependent on the number of decompositions of the nucleus excitation energy to energies of independent fermions. The calculation was based on the semi-classical model description in the computation of particle-hole state densities and then of the level densities ρ, and takes into account the existence of energy gaps Δ, located near the Fermi level, in a single particle level scheme. This procedure considerably improved and extended the Boehning calculation method. The results, which were obtained in this way for ρ, for 220 nuclei, reproduce the regularities observed in the experimental values of ρ, which are dependent on the neutron number N, and they agree with the experimental data within two orders of magnitude. In addition, the neutron resonance densities ρ were calculated on the basis of the particle-hole state densities obtained using the analytical formula from Boehning's paper. To make the calculations possible, the values of 'complexity' k, as given in the semi-classical model, and the spin factors R(J), according to the paper by Ryckbosch, were used
International Nuclear Information System (INIS)
Faure, F.
1993-01-01
This thesis deals with problems linked to the study of the semi-classical limit in quantum dynamics. The first part presents a geometrical formulation which is tantamount to the time dependent variational principle. The classical dynamics is considered as an orthogonal projection of the quantum dynamics on the family of coherent states. The angle of projection provides an information on the validity of the approximation. This angle is studied in an illustrating example. In the second part, we study quantum mechanics on the torus as a phase space, and particularly degeneracies in the spectrum of Harper like models or kicked Harper like models which manifest chaotic dynamics. These models find direct applications in solid state physics, especially with the quantum Hall effect. In this study, we use the Chern index, which is a topological characterization of the localization of the eigenfunctions as some periodicity conditions are changed. The use of the Husimi distribution provides a phase space representation of the quantum states. We discuss the role played by separatrix-states, by the effects of quantum tunneling, and by a classically chaotic dynamics. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Pinamonti, Nicola [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik
2010-01-15
In this paper we discuss the backreaction of a massive quantum scalar field on the curvature, the latter treated as a classical field. Furthermore, we deal with this problem in the realm of cosmological spacetime by analyzing the Einstein equations in a semiclassical fashion. More precisely, we show that, at least on small intervals of time, solutions for this interacting system exist. This result is achieved furnishing an iteration scheme and showing that it converges in the appropriate Banach space. Moreover, we show that the quantum states with good ultraviolet behavior (Hadamard property) used in order to obtain the backreaction will be completely individuated by their form on the initial surface if chosen to be lightlike. On large intervals of time the situation is more complicated but, if the spacetime is expanding, we show that the end limiting point of the evolution does not depend strongly on the quantum state, because, in this limit, the expectation values of the matter fields responsible for the backreaction do not depend on the particular homogeneous Hadamard state at all. Finally, we comment on the interpretation of the semiclassical Einstein equations for this kind of problems. Although the fluctuations of the expectation values of pointlike fields diverge, if the spacetime and the quantum state have a large spatial symmetry and if we consider the smeared fields on regions of large spatial volume, they tend to vanish. Assuming this point of view the semiclassical Einstein equations become more reliable. (orig.)
International Nuclear Information System (INIS)
Pinamonti, Nicola
2010-01-01
In this paper we discuss the backreaction of a massive quantum scalar field on the curvature, the latter treated as a classical field. Furthermore, we deal with this problem in the realm of cosmological spacetime by analyzing the Einstein equations in a semiclassical fashion. More precisely, we show that, at least on small intervals of time, solutions for this interacting system exist. This result is achieved furnishing an iteration scheme and showing that it converges in the appropriate Banach space. Moreover, we show that the quantum states with good ultraviolet behavior (Hadamard property) used in order to obtain the backreaction will be completely individuated by their form on the initial surface if chosen to be lightlike. On large intervals of time the situation is more complicated but, if the spacetime is expanding, we show that the end limiting point of the evolution does not depend strongly on the quantum state, because, in this limit, the expectation values of the matter fields responsible for the backreaction do not depend on the particular homogeneous Hadamard state at all. Finally, we comment on the interpretation of the semiclassical Einstein equations for this kind of problems. Although the fluctuations of the expectation values of pointlike fields diverge, if the spacetime and the quantum state have a large spatial symmetry and if we consider the smeared fields on regions of large spatial volume, they tend to vanish. Assuming this point of view the semiclassical Einstein equations become more reliable. (orig.)
International Nuclear Information System (INIS)
Buldyreva, J.; Margulès, L.; Motiyenko, R.A.; Rohart, F.
2013-01-01
Relaxation parameters for K-components (K≤6) of six J→J+1 rotational transitions (J=6, 10, 17, 22, 31 and 33) of CH 3 35 Cl perturbed by O 2 are measured at room temperature with Voigt, speed-dependent Voigt and Galatry profiles in order to probe the speed-dependence effects. With respect to the previous study of CH 3 35 Cl–N 2 system [Guinet et al., J Quant Spectrosc Radiat Transfer 2012;113:1113], higher active-gas pressures are reached, providing better signal-to-noise ratios, and the exact expression of the Beer–Lambert law is introduced in the fitting procedure, leading, among other advantages, to much more realistic low-pressure results. The broadening parameters of the considered lines are also computed by a semi-classical method for various relative velocities of colliders and the powers characterizing the dependence of the collisional cross-sections on relative speeds are deduced as functions of the rotational numbers J and K. Additional calculations performed with the Maxwell–Boltzmann distribution of velocities show no significant difference with the earlier results [Buldyreva et al., Phys Chem Chem Phys 2011;13:20326] obtained within the mean thermal velocity approximation. Weighted sums of the presently measured Voigt-profile O 2 -broadening parameters and of the previously published N 2 -broadening ones are calculated to yield experimental air-broadening coefficients for spectroscopic databases. -- Highlights: • Analysis of the speed dependence of relaxation rates of CH 3 Cl lines. • Introduction of the Beer–Lambert law in analysis of line-shapes recorded by FM technique. • Comparison of Maxwell–Boltzmann averaging and mean thermal velocity calculations. • Estimation of air-induced broadening for CH 3 Cl rotational lines
International Nuclear Information System (INIS)
Kreye, W.C.
2007-01-01
New quantum-mechanical (QM) and semi-classical (SC) shifts (d's) and widths (HWHM's, w's) were measured from the line core of computed full spectral-line shapes for the Ar-perturbed/K-radiator system (K/Ar). The initial state of our model was based on a 4p 2 P 3/2,1/2 pseudo-potential for the K/Ar system, and the final state on a zero potential. The Fourier transform of the line shape formed the basis for the computations. Excellent agreement was found between the QM and SC values of d and of w in a high-pressure (P) non-impact region, which was characterized by a √P dependence of w and a P dependence of d. These agreements were shown to be another example of a correspondence between classical (SC) quantities and QM quantities in the limit of large quantum numbers. Typically at P=1x10 6 Torr and T=400 K, w QM =448 cm -1 and w SC =479 cm -1 , where the deviation from the mean is ±3.3%. Also, d QM =-3815 cm -1 and d SC =-3716 cm -1 , where the deviation from the mean is ±1.3%. A new general method was formulated which yielded a definite pressure P 0 , which was defined as an upper limit to the low-pressure impact approximation and a lower limit to the non-impact region
A quantum model of option pricing: When Black-Scholes meets Schrödinger and its semi-classical limit
Contreras, Mauricio; Pellicer, Rely; Villena, Marcelo; Ruiz, Aaron
2010-12-01
The Black-Scholes equation can be interpreted from the point of view of quantum mechanics, as the imaginary time Schrödinger equation of a free particle. When deviations of this state of equilibrium are considered, as a product of some market imperfection, such as: Transaction cost, asymmetric information issues, short-term volatility, extreme discontinuities, or serial correlations; the classical non-arbitrage assumption of the Black-Scholes model is violated, implying a non-risk-free portfolio. From Haven (2002) [1] we know that an arbitrage environment is a necessary condition to embedding the Black-Scholes option pricing model in a more general quantum physics setting. The aim of this paper is to propose a new Black-Scholes-Schrödinger model based on the endogenous arbitrage option pricing formulation introduced by Contreras et al. (2010) [2]. Hence, we derive a more general quantum model of option pricing, that incorporates arbitrage as an external time dependent force, which has an associated potential related to the random dynamic of the underlying asset price. This new resultant model can be interpreted as a Schrödinger equation in imaginary time for a particle of mass 1/σ2 with a wave function in an external field force generated by the arbitrage potential. As pointed out above, this new model can be seen as a more general formulation, where the perfect market equilibrium state postulated by the Black-Scholes model represent a particular case. Finally, since the Schrödinger equation is in place, we can apply semiclassical methods, of common use in theoretical physics, to find an approximate analytical solution of the Black-Scholes equation in the presence of market imperfections, as it is the case of an arbitrage bubble. Here, as a numerical illustration of the potential of this Schrödinger equation analogy, the semiclassical approximation is performed for different arbitrage bubble forms (step, linear and parabolic) and compare with the exact
Directory of Open Access Journals (Sweden)
W. C. Kreye
2010-01-01
Full Text Available Quantum-mechanical and semi-classical spectral-line shapes are computed at =400, 800, and 1000 K for the line core of the 5802 Å line of the Ar-Perturbed/K-Radiator system. HWHMs ('s are measured from computed full spectral-line shapes. The final-state pseudopotential is for the 721/2 state, and the initial-state potential is for the 423/2,3/2 state. Three high-pressure (P log(—versus—log( curves, corresponding to the non-impact region, intersect a similar set of low-P, impact-region curves at intersections, 0's. Similarly, for two sets of log(—versus—log( curves, which yield intersections, 0's, where is the perturber density. These 0's and 0's separate the two regions and represent the upper limits of the impact regions. A specific validity condition for the impact region is given by the equation ≤0. From an earlier spectroscopic, Fabry-Perot paper, expt=0.021 cm−1 at =400 K and =10 torr. Two theoretical values, theor=0.025 and 0.062 cm−1 corresponding to two different pseudo-potentials, are reported. Two -dependent figures are given, in which the first shows an increase in the impact region with , based on as the basic parameter, and the second which shows a decrease in the impact region with , based on as the basic parameter.
Caustics, counting maps and semi-classical asymptotics
International Nuclear Information System (INIS)
Ercolani, N M
2011-01-01
This paper develops a deeper understanding of the structure and combinatorial significance of the partition function for Hermitian random matrices. The coefficients of the large N expansion of the logarithm of this partition function, also known as the genus expansion (and its derivatives), are generating functions for a variety of graphical enumeration problems. The main results are to prove that these generating functions are, in fact, specific rational functions of a distinguished irrational (algebraic) function, z 0 (t). This distinguished function is itself the generating function for the Catalan numbers (or generalized Catalan numbers, depending on the choice of weight of the parameter t). It is also a solution of the inviscid Burgers equation for certain initial data. The shock formation, or caustic, of the Burgers characteristic solution is directly related to the poles of the rational forms of the generating functions. As an intriguing application, one gains new insights into the relation between certain derivatives of the genus expansion, in a double-scaling limit, and the asymptotic expansion of the first Painlevé transcendent. This provides a precise expression of the Painlevé asymptotic coefficients directly in terms of the coefficients of the partial fractions expansion of the rational form of the generating functions established in this paper. Moreover, these insights point towards a more general program relating the first Painlevé hierarchy to the higher order structure of the double-scaling limit through the specific rational structure of generating functions in the genus expansion. The paper closes with a discussion of the relation of this work to recent developments in understanding the asymptotics of graphical enumeration. As a by-product, these results also yield new information about the asymptotics of recurrence coefficients for orthogonal polynomials with respect to exponential weights, the calculation of correlation functions for certain tied random walks on a 1D lattice, and the large time asymptotics of random matrix partition functions
The semi-classical limit of large fermionic systems
DEFF Research Database (Denmark)
Lewin, Mathieu; Fournais, Søren; Solovej, Jan Philip
2018-01-01
the convergence to the Thomas-Fermi minimizers in the limit $N\\to\\infty$. The limit is expressed using many-particle coherent states and Wigner functions. The method of proof is based on a fermionic de Finetti-Hewitt-Savage theorem in phase space and on a careful analysis of the possible lack of compactness...
Caustics, counting maps and semi-classical asymptotics
Ercolani, N. M.
2011-02-01
This paper develops a deeper understanding of the structure and combinatorial significance of the partition function for Hermitian random matrices. The coefficients of the large N expansion of the logarithm of this partition function, also known as the genus expansion (and its derivatives), are generating functions for a variety of graphical enumeration problems. The main results are to prove that these generating functions are, in fact, specific rational functions of a distinguished irrational (algebraic) function, z0(t). This distinguished function is itself the generating function for the Catalan numbers (or generalized Catalan numbers, depending on the choice of weight of the parameter t). It is also a solution of the inviscid Burgers equation for certain initial data. The shock formation, or caustic, of the Burgers characteristic solution is directly related to the poles of the rational forms of the generating functions. As an intriguing application, one gains new insights into the relation between certain derivatives of the genus expansion, in a double-scaling limit, and the asymptotic expansion of the first Painlevé transcendent. This provides a precise expression of the Painlevé asymptotic coefficients directly in terms of the coefficients of the partial fractions expansion of the rational form of the generating functions established in this paper. Moreover, these insights point towards a more general program relating the first Painlevé hierarchy to the higher order structure of the double-scaling limit through the specific rational structure of generating functions in the genus expansion. The paper closes with a discussion of the relation of this work to recent developments in understanding the asymptotics of graphical enumeration. As a by-product, these results also yield new information about the asymptotics of recurrence coefficients for orthogonal polynomials with respect to exponential weights, the calculation of correlation functions for certain tied random walks on a 1D lattice, and the large time asymptotics of random matrix partition functions.
On Semi-classical Degravitation and the Cosmological Constant Problems
Patil, Subodh P
2010-01-01
In this report, we discuss a candidate mechanism through which one might address the various cosmological constant problems. We first observe that the renormalization of gravitational couplings (induced by integrating out various matter fields) manifests non-local modifications to Einstein's equations as quantum corrected equations of motion. That is, at the loop level, matter sources curvature through a gravitational coupling that is a non-local function of the covariant d'Alembertian. If the functional form of the resulting Newton's `constant' is such that it annihilates very long wavelength sources, but reduces to $1/M^2_{pl}$ ($M_{pl}$ being the 4d Planck mass) for all sources with cosmologically observable wavelengths, we would have a complimentary realization of the degravitation paradigm-- a realization through which its non-linear completion and the corresponding modified Bianchi identities are readily understood. We proceed to consider various theories whose coupling to gravity may a priori induce no...
Nonlocal formalism for nanoplasmonics: Phenomenological and semi-classical considerations
DEFF Research Database (Denmark)
Mortensen, N. Asger
2013-01-01
. Without specifying further details of the underlying physical mechanism we show how this leads to a Laplacian correction term in the electromagnetic wave equation. Within the hydrodynamic model we demonstrate this explicitly and we identify the characteristic nonlocal range to be ξNL∼vF/ω where v...
On semi-classical questions related to signal analysis
Helffer, Bernard; Laleg-Kirati, Taous-Meriem
2011-01-01
. Indeed it provides new spectral quantities that can give relevant information on some signals as it is the case for arterial blood pressure signal. © 2011 - IOS Press and the authors. All rights reserved.
Generalized Pareto optimum and semi-classical spinors
Rouleux, M.
2018-02-01
In 1971, S. Smale presented a generalization of Pareto optimum he called the critical Pareto set. The underlying motivation was to extend Morse theory to several functions, i.e. to find a Morse theory for m differentiable functions defined on a manifold M of dimension ℓ. We use this framework to take a 2 × 2 Hamiltonian ℋ = ℋ(p) ∈ 2 C ∞(T * R 2) to its normal form near a singular point of the Fresnel surface. Namely we say that ℋ has the Pareto property if it decomposes, locally, up to a conjugation with regular matrices, as ℋ(p) = u ‧(p)C(p)(u ‧(p))*, where u : R 2 → R 2 has singularities of codimension 1 or 2, and C(p) is a regular Hermitian matrix (“integrating factor”). In particular this applies in certain cases to the matrix Hamiltonian of Elasticity theory and its (relative) perturbations of order 3 in momentum at the origin.
Theoretical research in nuclear collective motion. Progress report
International Nuclear Information System (INIS)
1984-01-01
Progress is summarized on the following research projects: generalized density matrix method, large amplitude collective motion, boson mappings for the Interacting Boson Model, and semi-classical method for testing IBM hypothesis
The method of finite-gap integration in classical and semi-classical string theory
International Nuclear Information System (INIS)
Vicedo, Benoit
2011-01-01
In view of proving the AdS/CFT correspondence one day, a deeper understanding of string theory on certain curved backgrounds such as AdS 5 x S 5 is required. In this review we make a step in this direction by focusing on RxS 3 . It was discovered in recent years that string theory on AdS 5 x S 5 admits a Lax formulation. However, the complete statement of integrability requires not only the existence of a Lax formulation but also that the resulting integrals of motion are in pairwise involution. This idea is central to the first part of this review. Exploiting this integrability we apply algebro-geometric methods to string theory on RxS 3 and obtain the general finite-gap solution. The construction is based on an invariant algebraic curve previously found in the AdS 5 x S 5 case. However, encoding the dynamics of the solution requires specification of additional marked points. By restricting the symplectic structure of the string to these algebro-geometric data we derive the action-angle variables of the system. We then perform a first-principle semiclassical quantization of string theory on RxS 3 as a toy model for strings on AdS 5 x S 5 . The result is exactly what one expects from the dual gauge theory perspective, namely the underlying algebraic curve discretizes in a natural way. We also derive a general formula for the fluctuation energies around the generic finite-gap solution. The ideas used can be generalized to AdS 5 x S 5 . (review)
Outcome Research in Classical Psychodrama.
Kellermann, Peter Felix
1987-01-01
Examines various aspects of psychodrama outcome research and summarizes in tabular form 23 outcome studies published between 1952 and 1985, interpreting them as a whole. Concludes that psychodrama constitutes a valid alternative to other therapeutic approaches, especially in promoting behavior change in adjustment, antisocial, and related…
Semi-classical analysis for nonlinear Schrödinger equations
Carles, Remi
2008-01-01
These lecture notes review recent results on the high-frequency analysis of nonlinear Schrödinger equations in the presence of an external potential. The book consists of two relatively independent parts: WKB analysis, and caustic crossing. In the first part, the basic linear WKB theory is constructed and then extended to the nonlinear framework. The most difficult supercritical case is discussed in detail, together with some of its consequences concerning instability phenomena. Applications of WKB analysis to functional analysis, in particular to the Cauchy problem for nonlinear Schrödinger e
Electro-Acoustic Behavior of the Mitotic Spindle: A Semi-Classical Coarse-Grained Model
Czech Academy of Sciences Publication Activity Database
Havelka, Daniel; Kučera, Ondřej; Deriu, M.A.; Cifra, Michal
2014-01-01
Roč. 9, č. 1 (2014), e86501 E-ISSN 1932-6203 R&D Projects: GA ČR(CZ) GAP102/11/0649 Institutional support: RVO:67985882 Keywords : electric fields * tubulin * chromosomes Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 3.234, year: 2014
Global thermodynamics of confined inhomogeneous dilute gases: A semi-classical approach
Poveda-Cuevas, F. J.; Reyes-Ayala, I.; Seman, J. A.; Romero-Rochín, V.
2018-04-01
In this work we present our contribution to the Latin American School of Physics "Marcos Moshinsky" 2017 on Quantum Correlations which was held in Mexico City during the summer of 2017. We review the efforts that have been done to construct a global thermodynamic description of ultracold dilute gases confined in inhomogeneous potentials. This is difficult because the presence of this non-uniform trap makes the pressure of the gas to be a spatially dependent variable and its volume an ambiguously defined quantity. In this paper we introduce new global thermodynamic variables, equivalent to pressure and volume, and propose a realistic model of the equation of state of the system. This model is based on a mean-field approach which asymptotically reaches the Thomas-Fermi limit for a weakly interacting Bose gas. We put special emphasis to the transition between the normal and superfluid phases by studying the behavior of the isothermal compressibility across the transition. We reveal how the potential modifies the critical properties of the transition by determining the critical exponents associated to the divergences not of the susceptibilities but of their derivatives.
A semi-classical approach to signature splitting and signature inversion in odd–odd nuclei
International Nuclear Information System (INIS)
Kumar, Vinod; Kumar, Suresh; Kumar, Sushil; Hasan, Zafrul; Koranga, B.S.; Kumar, Deepak; Negi, D.; Angus, Lee
2011-01-01
The signature inversion observed in rotational bands belonging to high-j configurations of odd–odd deformed nuclei has been analyzed within the framework of an axially symmetric rotor plus two-particle model. The Coriolis and n–p interaction are considered the main cause of energy staggering. However, γ-triaxial deformation and the numbers of valence protons, N p , and neutrons, N n also contribute to the energy staggering between odd- and even-spin states. (author)
Particle on a torus knot: Constrained dynamics and semi-classical quantization in a magnetic field
Energy Technology Data Exchange (ETDEWEB)
Das, Praloy, E-mail: praloydasdurgapur@gmail.com; Pramanik, Souvik, E-mail: souvick.in@gmail.com; Ghosh, Subir, E-mail: subirghosh20@gmail.com
2016-11-15
Kinematics and dynamics of a particle moving on a torus knot poses an interesting problem as a constrained system. In the first part of the paper we have derived the modified symplectic structure or Dirac brackets of the above model in Dirac’s Hamiltonian framework, both in toroidal and Cartesian coordinate systems. This algebra has been used to study the dynamics, in particular small fluctuations in motion around a specific torus. The spatial symmetries of the system have also been studied. In the second part of the paper we have considered the quantum theory of a charge moving in a torus knot in the presence of a uniform magnetic field along the axis of the torus in a semiclassical quantization framework. We exploit the Einstein–Brillouin–Keller (EBK) scheme of quantization that is appropriate for multidimensional systems. Embedding of the knot on a specific torus is inherently two dimensional that gives rise to two quantization conditions. This shows that although the system, after imposing the knot condition reduces to a one dimensional system, even then it has manifested non-planar features which shows up again in the study of fractional angular momentum. Finally we compare the results obtained from EBK (multi-dimensional) and Bohr–Sommerfeld (single dimensional) schemes. The energy levels and fractional spin depend on the torus knot parameters that specifies its non-planar features. Interestingly, we show that there can be non-planar corrections to the planar anyon-like fractional spin.
Semi-classical analysis of the inner product of Bethe states
International Nuclear Information System (INIS)
Bettelheim, Eldad; Kostov, Ivan
2014-01-01
We study the inner product of two Bethe states, one of which is taken on-shell, in an inhomogeneous XXX chain in the Sutherland limit, where the number of magnons is comparable with the length L of the chain and the magnon rapidities arrange in a small number of macroscopically large Bethe strings. The leading order in the large L limit is known to be expressed through a contour integral of a dilogarithm. Here we derive the sub-leading term. Our analysis is based on a new contour-integral representation of the inner product in terms of a Fredholm determinant. We give two derivations of the sub-leading term. Besides a direct derivation by solving a Riemann–Hilbert problem, we give a less rigorous, but more intuitive derivation by field-theoretical methods. For that we represent the Fredholm determinant as an expectation value in a Fock space of chiral fermions and then bosonize. We construct a collective field for the bosonized theory, the short wave-length part of which may be evaluated exactly, while the long wave-length part is amenable to a 1/L expansion. Our treatment thus results in a systematic 1/L expansion of structure factors within the Sutherland limit. (paper)
Medium energy nucleon-nucleus scattering theory by semi-classical distorted wave approximation
Energy Technology Data Exchange (ETDEWEB)
Ogata, Kazuyuki [Kyushu Univ., Fukuoka (Japan)
1998-07-01
The semiclassical distorted wave model (SCDW) is one of the quantum mechanical models for nucleon inelastic and charge exchange scattering at intermediate energies. SCDW can reproduce the double differential inclusive cross sections for multi-step direct processes quite well in the angular and outgoing energy regions where the model is expected to work. But the model hitherto assumed on-the-energy-shell (on-shell) nucleon-nucleon scattering in the nucleus, neglecting the difference in the distorting potentials for the incoming and the outgoing particles and also the Q-value in the case of (p,n) reactions. There had also been a problem in the treatment of the exchange of colliding nucleons. Now we modify the model to overcome those problems and put SCDW on sounder theoretical foundations. The modification results in slight reduction (increase) of double differential cross sections at forward (backward) angles. We also examine the effect of the in-medium modification of N-N cross sections in SCDW and find it small. A remedy of the disagreement at very small and large angles in terms of the Wigner transform of the single particle density matrix is also discussed. This improvement gives very promising results. (author)
Foundational principles of classical Ayurveda research
Directory of Open Access Journals (Sweden)
Somik Raha
2013-01-01
Full Text Available Double-blind randomized controlled trials (RCTs are viewed as the golden standard of drug research in Western medicine. However, RCTs are far from "golden" in many respects. They are impractical for many therapies, such as for surgeries and complex lifestyle changes. They encourage a one-size-fits-all approach to medical treatment that fails to address the huge diversity among individual patients in terms of their physical and emotional symptoms, social and cultural upbringing, and other factors. Perhaps, more importantly, they do not help doctors make the best medical decisions required to produce optimal patient outcomes. To guide a search for an alternate model of medical research, three principles based on Ayurveda, an ancient and powerful system of health care that has stood the test of time, are presented. These principles, arrived at after mining Ayurvedic epistemology, are: Inductive learning, whole systems thinking, and individually optimized therapy. In honor of the ancient sages or "Rishis," whose voice is used to deliver Ayurvedic knowledge in the ancient texts of Ayurveda, these are referred to as the "Rishi principles." Individually optimized therapy is interpreted using the lens of decision analysis. Common research methodologies are examined for embodiment of these principles.
The nonlinear dynamics of the classical few body problem
International Nuclear Information System (INIS)
Tabor, M.
1981-01-01
The complicated behavior that small dynamical systems can display is reviewed and its relevance to such diverse fields as celestial mechanics, semi-classical mechanics and fluid dynamics is discussed. (orig.)
Amour, Laurent; Khodja, Mohamed; Nourrigat, Jean
2011-01-01
We study the Wick symbol of a solution of the time dependent Hartree Fock equation, under weaker hypotheses than those needed for the Weyl symbol in the first paper with thesame title. With similar, we prove some kind of Ehrenfest theorem for observables that are not pseudo-differential operators.
Directory of Open Access Journals (Sweden)
Teresa D'Aprile
2000-11-01
Full Text Available In this paper we study the existence of concentrated solutions of the nonlinear field equation $$ -h^{2}Delta v+V(xv-h^{p}Delta_{p}v+ W'(v=0,, $$ where $v:{mathbb R}^{N}o{mathbb R}^{N+1}$, $Ngeq 3$, $p>N$, the potential $V$ is positive and radial, and $W$ is an appropriate singular function satisfying a suitable symmetric property. Provided that $h$ is sufficiently small, we are able to find solutions with a certain spherical symmetry which exhibit a concentration behaviour near a circle centered at zero as $ho 0^{+}$. Such solutions are obtained as critical points for the associated energy functional; the proofs of the results are variational and the arguments rely on topological tools. Furthermore a penalization-type method is developed for the identification of the desired solutions.
Indian Academy of Sciences (India)
2013-11-11
Nov 11, 2013 ... Polanyi's classic paper, co-authored by Henry Eyring, reproduced in this ... spatial conf guration of the atoms in terms of the energy function of the diatomic .... The present communication deals with the construction of such .... These three contributions are complemented by a fourth term if one takes into.
Bohmian measures and their classical limit
Markowich, Peter
2010-09-01
We consider a class of phase space measures, which naturally arise in the Bohmian interpretation of quantum mechanics. We study the classical limit of these so-called Bohmian measures, in dependence on the scale of oscillations and concentrations of the sequence of wave functions under consideration. The obtained results are consequently compared to those derived via semi-classical Wigner measures. To this end, we shall also give a connection to the theory of Young measures and prove several new results on Wigner measures themselves. Our analysis gives new insight on oscillation and concentration effects in the semi-classical regime. © 2010 Elsevier Inc.
Continuing research on the classical spiraling photon model
Li, Hongrui
2014-11-01
Based no the classical spiraling photon model proposed by Hongrui Li, the laws of reflection, refraction of a single photon can be derived. Moreover, the polarization, total reflection, evanescent wave and Goos-Hanchen shift of a single photon can be elucidated. However, this photon model is still unfinished. Especially, the spiraling diameter of a photon is not definite. In this paper, the continuous research works on this new theory are reported. According to the facts that the diffraction limit of light and the smallest diameter of the focal spot of lenses are all equal to the wavelength λ of the light, we can get that the spiraling diameter of a photon equals to the wavelength λ, so we gain that the angle between the linear velocity of the spiraling photon υ and the component of the linear velocity in the forward direction υb is 45°, and the energy of a classical spiraling photon E = (1/2)mυ2 = (1/2)m2c2 = mc2. This coincides with Einstein's mass-energy relation. While it is obtained that the velocity of the evanescent wave in the vacuum is slower than the velocity of light in glass in straight line. In such a way, the optical fiber can slow the light down. In addition, the force analysis of a single photon in optical tweezers system is discussed. And the reason that the laser beam can capture the particle slightly downstream from the focal point can be explained.
Quantum remnants in the classical limit
International Nuclear Information System (INIS)
Kowalski, A.M.; Plastino, A.
2016-01-01
We analyze here the common features of two dynamical regimes: a quantum and a classical one. We deal with a well known semi-classic system in its route towards the classical limit, together with its purely classic counterpart. We wish to ascertain i) whether some quantum remnants can be found in the classical limit and ii) the details of the quantum-classic transition. The so-called mutual information is the appropriate quantifier for this task. Additionally, we study the Bandt–Pompe's symbolic patterns that characterize dynamical time series (representative of the semi-classical system under scrutiny) in their evolution towards the classical limit. - Highlights: • We investigate the classical limit (CL) of a well known semi classical model. • The study is made by reference to the Bandt Pompe symbolic approach. • The number and type of associated symbols changes as one proceeds towards the CL. • We ascertain which symbols pertaining to the quantum zone remain in the CL.
Quantum remnants in the classical limit
Energy Technology Data Exchange (ETDEWEB)
Kowalski, A.M., E-mail: kowalski@fisica.unlp.edu.ar [Instituto de Física (IFLP-CCT-Conicet), Universidad Nacional de La Plata, C.C. 727, 1900 La Plata (Argentina); Comision de Investigaciones Científicas (CIC) (Argentina); Plastino, A., E-mail: plastino@fisica.unlp.edu.ar [Instituto de Física (IFLP-CCT-Conicet), Universidad Nacional de La Plata, C.C. 727, 1900 La Plata (Argentina); Argentina' s National Research Council (CONICET) (Argentina); SThAR, EPFL Innovation Park, Lausanne (Switzerland)
2016-09-16
We analyze here the common features of two dynamical regimes: a quantum and a classical one. We deal with a well known semi-classic system in its route towards the classical limit, together with its purely classic counterpart. We wish to ascertain i) whether some quantum remnants can be found in the classical limit and ii) the details of the quantum-classic transition. The so-called mutual information is the appropriate quantifier for this task. Additionally, we study the Bandt–Pompe's symbolic patterns that characterize dynamical time series (representative of the semi-classical system under scrutiny) in their evolution towards the classical limit. - Highlights: • We investigate the classical limit (CL) of a well known semi classical model. • The study is made by reference to the Bandt Pompe symbolic approach. • The number and type of associated symbols changes as one proceeds towards the CL. • We ascertain which symbols pertaining to the quantum zone remain in the CL.
Šimović, Vladimir
2001-01-01
The objective of this study is to present research on classical and intelligent information system solutions used in criminal intelligence analysis in Croatian security system theory. The study analyses objective and classical methods of information science, including artificial intelligence and other scientific methods. The intelligence and classical software solutions researched, proposed, and presented in this study were used in developing the integrated information system for the Croatian...
International Nuclear Information System (INIS)
Creighton, J.R.
1975-01-01
Waveforms and population distributions have been calculated by a numerical model and compared with experiment for an electric-discharge-initiated, pulsed NF 3 + H 2 chemical laser. The model treats each vibrational-rotational state separately, allowing rotational relaxation between adjacent states as well as vibrational relaxation and lasing according to P-branch selection rules. Calculated waveforms agree with experiment and show several features not seen when rotational equilibrium is assumed: simultaneous lasing on many transitions, cascade behavior, spikes due to laser relaxation oscillations, non-Boltzmann rotational distributions, and ''hole burning'' in the population distributions. The calculations give insight into the physical phenomena governing the shape and duration of the waveforms. The effect of varying certain parameters, relaxation rates, temperature, pressure, and diluents, is studied. Best fit to experimental waveforms is obtained when the rotational relaxation rate and collisional line broadening rate are approximately equal at about 10 times the hard sphere collision rate. The IXION computer code, developed for these calculations, is described in detail. In addition, an analytic model is presented which accounts for major features of the total (all transitions) output waveform of the laser assuming rotational equilibrium, a steady state laser model, and constant temperature. A second computer code, MINOTAR, was developed as a general purpose chemical kinetics code. It verifies the analytic model and extends the results to adiabatic reactions where the temperature varies, and can yield waveforms using the assumptions of rotational equilibrium and a steady state laser. The MINOTAR code, being general, can also be used for chemical kinetics problems such as air pollution and combustion
Energy Technology Data Exchange (ETDEWEB)
Guimaraes, F.B.
2002-03-07
In this work we describe neutron and proton induced reaction cross-sections for iron produced by the codes TNG and CEM95 in the 5 to 300 MeV energy range. TNG calculations cover the 5-90 MeV range, while CEM95 covers the 50-300 MeV high energy range. The two codes show some disagreements in the overlap energy range, both among themselves and with the experimental data, which are presently being addressed. The experimental data used are from NNDC and/or from LA150 NSE references. We also describe some developments for combining TNG and CEM95 into a new code called CETNG (Cascade Exciton TNG).
Lorin, E.; Yang, X.; Antoine, X.
2016-06-01
The paper is devoted to develop efficient domain decomposition methods for the linear Schrödinger equation beyond the semiclassical regime, which does not carry a small enough rescaled Planck constant for asymptotic methods (e.g. geometric optics) to produce a good accuracy, but which is too computationally expensive if direct methods (e.g. finite difference) are applied. This belongs to the category of computing middle-frequency wave propagation, where neither asymptotic nor direct methods can be directly used with both efficiency and accuracy. Motivated by recent works of the authors on absorbing boundary conditions (Antoine et al. (2014) [13] and Yang and Zhang (2014) [43]), we introduce Semiclassical Schwarz Waveform Relaxation methods (SSWR), which are seamless integrations of semiclassical approximation to Schwarz Waveform Relaxation methods. Two versions are proposed respectively based on Herman-Kluk propagation and geometric optics, and we prove the convergence and provide numerical evidence of efficiency and accuracy of these methods.
International Nuclear Information System (INIS)
Smith, Kyle K. G.; Rossky, Peter J.; Poulsen, Jens Aage; Cunsolo, A.
2014-01-01
The dynamic structure factor of liquid para-hydrogen and ortho-deuterium in corresponding thermodynamic states (T = 20.0 K, n = 21.24 nm −3 ) and (T = 23.0 K, n = 24.61 nm −3 ), respectively, has been computed by both the Feynman-Kleinert linearized path-integral (FK-LPI) and Ring-Polymer Molecular Dynamics (RPMD) methods and compared with Inelastic X Ray Scattering spectra. The combined use of computational and experimental methods enabled us to reduce experimental uncertainties in the determination of the true sample spectrum. Furthermore, the refined experimental spectrum of para-hydrogen and ortho-deuterium is consistently reproduced by both FK-LPI and RPMD results at momentum transfers lower than 12.8 nm −1 . At larger momentum transfers the FK-LPI results agree with experiment much better for ortho-deuterium than for para-hydrogen. More specifically we found that for k ∼ 20.0 nm −1 para-hydrogen provides a test case for improved approximations to quantum dynamics
[Constructing climate. From classical climatology to modern climate research].
Heymann, Matthias
2009-01-01
Both climate researchers and historians of climate science have conceived climate as a stable and well defined category. This article argues that such a conception is flawed. In the course of the 19th and 20th century the very concept of climate changed considerably. Scientists came up with different definitions and concepts of climate, which implied different understandings, interests, and research approaches. Understanding climate shifted from a timeless, spatial concept at the end of the 19th century to a spaceless, temporal concept at the end of the 20th. Climatologists in the 19th and early 20th centuries considered climate as a set of atmospheric characteristics associated with specific places or regions. In this context, while the weather was subject to change, climate remained largely stable. Of particular interest was the impact of climate on human beings and the environment. In modern climate research at the close of the 20th century, the concept of climate lost its temporal stability. Instead, climate change has become a core feature of the understanding of climate and a focus of research interests. Climate has also lost its immediate association with specific geographical places and become global. The interest is now focused on the impact of human beings on climate. The paper attempts to investigate these conceptual shifts and their origins and impacts in order to provide a more comprehensive perspective on the history of climate research.
Verlegh, P.; Voorveld, H.; Eisend, M.
2016-01-01
This book provides insights into the inspiring and multifaceted field of advertising research, which is confronted with challenges regarding ad content and execution, media placement, as well as online and social media. Distinguishing between digital, classic, subtle, and alternative advertising
Top 100 Cited Classic Articles in Breast Cancer Research.
Uysal, Erdal
2017-07-01
This study aimed to analyze 100 most cited articles in breast cancer research. The data in this study were obtained by a search conducted on the Web of Science (WOS). In brief, the term "breast cancer" was typed in the search box of WOS basic research including all the years and the data. The analysis was carried out by compiling the top 100 cited articles in the shortlist as sorted by the journals, categories of the studies, the countries, the centers, the authors and the publication date. No statistical methods were used in the study. All data were reported as percentages, numbers and bar charts on tables. Our findings showed that the most frequently cited article received 7609 citations to date. Most articles were published in the New England Journal of Medicine. 81% of the studies originated from the USA. The National Institutes of Health (NIH USA) was ranked the first with 21% and it was followed by Harvard University in terms of number of published articles. 42% of the articles were published under the category of medicine and general internal medicine. Top 100 most cited articles originated from the United States. The highest number of articles among the top 100 articles were published in New England Journal of Medicine and National Institutes of Health NIH USA was the leading institutes published the most articles.
A classical model for the electron
International Nuclear Information System (INIS)
Visser, M.
1989-01-01
The construction of classical and semi-classical models for the electron has had a long and distinguished history. Such models are useful more for what they teach us about field theory than what they teach us about the electron. In this Letter I exhibit a classical model of the electron consisting of ordinary electromagnetism coupled with a self-interacting version of Newtonian gravity. The gravitational binding energy of the system balances the electrostatic energy in such a manner that the total rest mass of the electron is finite. (orig.)
On the quantization of classically chaotic system
International Nuclear Information System (INIS)
Godoy, N.F. de.
1988-01-01
Some propeties of a quantization in terms of observables of a classically chaotic system, which exhibits a strange are studied. It is shown in particular that convenient expected values of some observables have the correct classical limit and that in these cases the limits ℎ → O and t → ∞ (t=time) rigorously comute. This model was alternatively quantized by R.Graham in terms of Wigner function. The Graham's analysis is completed a few points, in particular, we find out a remarkable analogy with general results about the semi-classical limit of Wigner function. Finally the expected values obtained by both methods of quantization were compared. (author) [pt
Classical limit of quantum gravity in an accelerating universe
International Nuclear Information System (INIS)
Schuller, Frederic P.; Wohlfarth, Mattias N.R.
2005-01-01
A one-parameter deformation of Einstein-Hilbert gravity with an inverse Riemann curvature term is derived as the classical limit of quantum gravity compatible with an accelerating universe. This result is based on the investigation of semi-classical theories with sectional curvature bounds which are shown not to admit static spherically symmetric black holes if otherwise of phenomenological interest. We discuss the impact on the canonical quantization of gravity, and observe that worldsheet string theory is not affected
Classical integrability for three-point functions: cognate structure at weak and strong couplings
Energy Technology Data Exchange (ETDEWEB)
Kazama, Yoichi [Research Center for Mathematical Physics, Rikkyo University,Toshima-ku, Tokyo 171-8501 (Japan); Quantum Hadron Physics Laboratory, RIKEN Nishina Center, Wako 351-0198 (Japan); Institute of Physics, University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Komatsu, Shota [Perimeter Institute for Theoretical Physics,31 Caroline Street North, Waterloo, Ontario, N2L 2Y5 (Canada); Nishimura, Takuya [Institute of Physics, University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan)
2016-10-10
In this paper, we develop a new method of computing three-point functions in the SU(2) sector of the N=4 super Yang-Mills theory in the semi-classical regime at weak coupling, which closely parallels the strong coupling analysis. The structure threading two disparate regimes is the so-called monodromy relation, an identity connecting the three-point functions with and without the insertion of the monodromy matrix. We shall show that this relation can be put to use directly for the semi-classical regime, where the dynamics is governed by the classical Landau-Lifshitz sigma model. Specifically, it reduces the problem to a set of functional equations, which can be solved once the analyticity in the spectral parameter space is specified. To determine the analyticity, we develop a new universal logic applicable at both weak and strong couplings. As a result, compact semi-classical formulas are obtained for a general class of three-point functions at weak coupling including the ones whose semi-classical behaviors were not known before. In addition, the new analyticity argument applied to the strong coupling analysis leads to a modification of the integration contour, producing the results consistent with the recent hexagon bootstrap approach. This modification also makes the Frolov-Tseytlin limit perfectly agree with the weak coupling form.
Classical Natural History: the importance of volunteers in collection management and research
Reumer, J.W.F.; Post, K.
2010-01-01
As a result of increasing budget constraints and decreasing interest in classical natural history, the work effort of volunteer researchers and the need for private funding are of growing importance. A brief historical background is provided, showing the decreasing interest in the subject shown by
A century of research on the classical locality of Tegelen (province of Limburg, The Netherlands)
Hoek Ostende, van den L.W.; Vos, de J.
2006-01-01
In 1904 Eugène Dubois published the first report on fossil mammals from the vicinity of Tegelen. After a century of research the clay-pits from the area are known as a classical locality for Villafranchian mammals. Antje Schreuder's work was particularly important for making the fossils from Tegelen
From classic to current: a look back on attention research in the American Journal of Psychology.
Mounts, Jeffrey R W
2012-01-01
This review examines attention research appearing in The American Journal of Psychology over the journal's rich 125-year history. In particular, the review examines studies focused on selective attention's role in modulating the influence of distraction and the methods used to capture the nature of selective attention. Special attention is given to classic articles by Treisman (1964a, 1964b), Neisser (1963), and Eriksen and Rohrbaugh (1970), whose methods and results are examined in detail in light of current theory and research in selective attention.
Excursions in classical analysis pathways to advanced problem solving and undergraduate research
Chen, Hongwei
2010-01-01
Excursions in Classical Analysis introduces undergraduate students to advanced problem solving and undergraduate research in two ways. Firstly, it provides a colourful tour of classical analysis which places a wide variety of problems in their historical context. Secondly, it helps students gain an understanding of mathematical discovery and proof. In demonstrating a variety of possible solutions to the same sample exercise, the reader will come to see how the connections between apparently inapplicable areas of mathematics can be exploited in problem-solving. This book will serve as excellent preparation for participation in mathematics competitions, as a valuable resource for undergraduate mathematics reading courses and seminars and as a supplement text in a course on analysis. It can also be used in independent study, since the chapters are free-standing.
Directory of Open Access Journals (Sweden)
Rodolfo Wendhausen Krause
2016-08-01
Full Text Available This study aims to synthesize the scientific knowledge with the empirical knowledge of the authors of this article on the four main types/styles of individual services in gastronomic full service establishments. In addition, it seeks to, as secondary objectives, to simplify and standardize the types of classic services in restaurants. These objectives were met through a positivist methodological approach. It had as research techniques a comparative analysis and synthesis of the state of the art on the typology of classical services with the empirical knowledge of the authors. Subsequently, the validation of standardization proposal was made by a panel of evaluators. We came to simplify the services into three basic categories: French Service; Direct English Service and Platted Service. It is understood that, because it is an exploratory study, the proposal is the beginning of scientific research on the subject. Therefore, it has to be investigated in greater depth in future studies. Therefore, the research field of the mise en place is the area that greater needs research of this nature.
Internet research: an opportunity to revisit classic ethical problems in behavioral research.
Pittenger, David J
2003-01-01
The Internet offers many new opportunities for behavioral researchers to conduct quantitative and qualitative research. Although the ethical guidelines of the American Psychological Association generalize, in part, to research conducted through the Internet, several matters related to Internet research require further analysis. This article reviews several fundamental ethical issues related to Internet research, namely the preservation of privacy, the issuance of informed consent, the use of deception and false feedback, and research methods. In essence, the Internet offers unique challenges to behavioral researchers. Among these are the need to better define the distinction between private and public behavior performed through the Internet, ensure mechanisms for obtaining valid informed consent from participants and performing debriefing exercises, and verify the validity of data collected through the Internet.
Linking contemporary research to the classics: Celebrating 125 years at APA.
Enns, James T; Becker, Stefanie I; Brockmole, James; Castelhano, Monica; Creem-Regehr, Sarah; Gray, Rob; Hecht, Heiko; Juhasz, Barbara; Philbeck, John; Woodman, Geoffrey
2017-10-01
APA is celebrating 125 years this year and at the journal we are commemorating this milestone with a special issue. The inspiration came from our editorial team, who wished to acknowledge the links between game-changing articles that have influenced our research community in the past-we call them classics for short-and contemporary works. The main idea was to feature the work of nine contemporary research teams, while at the same time drawing readers' attention to their links with the classics. In this introduction, we have organized the articles according to several broad themes: active perception, perception for action, action alters perception, perception of our bodies in action, and acting on selective perceptions. As all who have read and contributed to the journal over the past few years have come to realize, it is no longer possible to study perception without considering its role in action. Nor is it possible to study action (formerly called performance , as reflected in the journal title) without understanding the perceptual contributions to action. These nine articles each exemplify, in their own way, how these dynamic interactions play out in contemporary research in our field. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
International Nuclear Information System (INIS)
Lee, Sang-Bong.
1993-09-01
Quantum manifestation of classical chaos has been one of the extensively studied subjects for more than a decade. Yet clear understanding of its nature still remains to be an open question partly due to the lack of a canonical definition of quantum chaos. The classical definition seems to be unsuitable in quantum mechanics partly because of the Heisenberg quantum uncertainty. In this regard, quantum chaos is somewhat misleading and needs to be clarified at the very fundamental level of physics. Since it is well known that quantum mechanics is more fundamental than classical mechanics, the quantum description of classically chaotic nature should be attainable in the limit of large quantum numbers. The focus of my research, therefore, lies on the correspondence principle for classically chaotic systems. The chaotic damped driven pendulum is mainly studied numerically using the split operator method that solves the time-dependent Schroedinger equation. For classically dissipative chaotic systems in which (multi)fractal strange attractors often emerge, several quantum dissipative mechanisms are also considered. For instance, Hoover's and Kubo-Fox-Keizer's approaches are studied with some computational analyses. But the notion of complex energy with non-Hermiticity is extensively applied. Moreover, the Wigner and Husimi distribution functions are examined with an equivalent classical distribution in phase-space, and dynamical properties of the wave packet in configuration and momentum spaces are also explored. The results indicate that quantum dynamics embraces classical dynamics although the classicalquantum correspondence fails to be observed in the classically chaotic regime. Even in the semi-classical limits, classically chaotic phenomena would eventually be suppressed by the quantum uncertainty
Citation classics in suicide and life threatening behavior: a research note.
Stack, Steven
2012-12-01
The number of citations a scholarly work receives is a common measure of its impact on the scientific literature; "citation classics" are the most highly cited works. The content of Suicide and Life-Threatening Behavior (SLTB) citation classics is described here. The impact of SLTB citation classics is compared to their counterparts in journals having published the most suicide papers. All data are from the ISI electronic venue on the Web of Science and refer to the number of citations the top 1% of works received in each of ten journals from 1975 through August 10, 2011. Among all ten journals, SLTB ranked first in the number of works on suicide. The principle theme of half of SLTB suicide classics was literature review. The median number of citations for SLTB citation classics (top 1%) was 121.5, with a range between 96 and 279 citations, but classics from generalized psychiatric journals received more citations as anticipated. Journal impact factors explained 73% of the variance in classic's citation counts across journals. On average, suicide classics received 30% more citations than all classics. Among a second group of five specialized suicide journals, however, SLTB ranked first in average 5-year impact. Although SLTB produced the highest number of suicide articles of any journal, SLTB's citation classics received fewer citations than suicide classics in high-impact/prestige, general journals. Future work is needed to assess what predicts which SLTB articles ultimately become citation classics. © 2012 The American Association of Suicidology.
Citation Classics in "Suicide and Life Threatening Behavior": A Research Note
Stack, Steven
2012-01-01
The number of citations a scholarly work receives is a common measure of its impact on the scientific literature; "citation classics" are the most highly cited works. The content of "Suicide and Life-Threatening Behavior" ("SLTB") citation classics is described here. The impact of "SLTB" citation classics is compared to their counterparts in…
Orthogonal polynomials, Laguerre Fock space, and quasi-classical asymptotics
Engliš, Miroslav; Ali, S. Twareque
2015-07-01
Continuing our earlier investigation of the Hermite case [S. T. Ali and M. Engliš, J. Math. Phys. 55, 042102 (2014)], we study an unorthodox variant of the Berezin-Toeplitz quantization scheme associated with Laguerre polynomials. In particular, we describe a "Laguerre analogue" of the classical Fock (Segal-Bargmann) space and the relevant semi-classical asymptotics of its Toeplitz operators; the former actually turns out to coincide with the Hilbert space appearing in the construction of the well-known Barut-Girardello coherent states. Further extension to the case of Legendre polynomials is likewise discussed.
Review of Digital Research in the Study of Classical Antiquity [Book
Directory of Open Access Journals (Sweden)
Adam Rabinowitz
2011-07-01
Full Text Available It is often stated that trying to deal with information on the internet is like drinking from a firehose. But trying to put together a book about the current state of digital anything must be rather more like trying to paint a landscape from the window of a moving train. By the time the painting is complete, the scenery has changed dramatically. This puts books on digital approaches to academic disciplines in an interesting position: by the time a volume makes it into the hands of its readers, it is already a historical document as well as a scholarly work. The editors of Digital Research in the Study of Classical Antiquity are very aware of this: as they state, the book seeks "to create a snapshot of the research activities of Digital Classicist members as represented by a selection of the papers given at our Summer seminars and conference panels in one particular year, 2007" (p10. When one considers that the printed volume went to press in 2010, and is being reviewed in 2011, this means that almost four years—a digital eternity—have passed since most of the papers were first composed. I think, therefore, it will be most useful to discuss Digital Research from two perspectives: first, in terms of its scholarly contribution, and second, in terms of what the framing of this work and the identity of its contributors tell us about a particular moment in the history of the field of 'digital humanities'.
How far can radiation from atoms be represented by classical models
International Nuclear Information System (INIS)
Haar, D. Ter; Wergeland, H.
1978-01-01
In recent years some phenomena currently assumed to be essentially quantal have found an accurate description in classical terms. An example is Lamb's semiclassical theory of the laser. Consequently many physicists are discussing in how far a full quantum mechanical treatment is necessary. A good many of the formulae for the radiation from atoms can certainly be obtained by classical methods. But these methods fail already at the question of the line profiles. Even though the damping is a simple mechanism - classically speaking. It seems inevitible that the semi-classical formulae must be limited to those phenomena which essentially only involve the averages of photon numbers. (JIW)
汉魏石经杂考%Miscellaneous Research on Han and Wei Stone Classics
Institute of Scientific and Technical Information of China (English)
王东洋
2017-01-01
汉魏石经包括东汉熹平石经、《典论》石经和正始石经，三者均开刻于当时的京城洛阳，在中国文化史上具有重要意义。汉魏石经由朝廷下诏刊刻，立于太学，供天下儒生观瞻临摹。在纸质书写材料尚未普及的汉魏时期，汉魏石经起到了统一经学、保存文化、宣扬教化的作用。%Han and Wei Stone Classics with Xiping Stone classics,Dianlun Stone classics and Zhengshi Stone classics were carved in Luoyang City,has great significance in the history of Chinese culture.Under the royal order,Han and Wei Stone Classics were inscribed and erected in the Imperial College for the confucian scholars to learn and copy.In view of the underpopularization of paper writing material,Han and Wei Stone Classics played the role of unifying confucian classics,preserving culture and preaching and teaching.
NATO Advanced Research Workshop on Squeezed and Non-classical Light
Pike, E; Squeezed and Non-classical Light
1988-01-01
The recent generation in the laboratory of phase squeezed and intensity squeezed light beams has brought to fruition the theoretical predictions of such non-classical phenomena which have been made and developed in recent years by a number of workers in the field of quantum optics. A vigorous development is now underway of both theory and experiment and the first measurements have been coi:Jfirmed and extended already in some half dozen laboratories. Although the fields of application of these novellight sources are as yet somewhat hazy in our minds and some inspired thinking is required along these lines, the pace and excitement of the research is very clear. It is to he hoped that the new possibilities of: making measurements below the quantum shot noise lirnit which is made possible by these squeezed states of light willlead to further fundamental advances in the near future. In this NATO ARW a number of the leaders in the field met in the extremely pleasant surroundings of Cortina d'Ampezzo and th...
Non-classical neutron beams for fundamental and solid state research
International Nuclear Information System (INIS)
Rauch, H.
2008-01-01
The curious dual nature of the neutron, sometimes a particle, sometimes a wave, is wonderfully manifested in the various non-local interference and quantum contextuality effects observed in neutron interferometry. Non-classical states may become useful for novel fundamental and solid state research. Here we discuss unavoidable quantum losses as they appear in neutron phase-echo and spin rotation experiments and we show how entanglement effects in a single particle system demonstrate quantum contextuality. In all cases of interactions, parasitic beams are produced which cannot be recombined completely with the original beam. This means that a complete reconstruction of the original state would, in principle, be impossible which causes a kind of intrinsic irreversibility. Even small interaction potentials can have huge effects when they are applied in quantum Zeno-like experiments. Recently, it has been shown that an entanglement between external and internal degrees of freedom exists even in single particle systems. This contextuality phenomenon also shows that a quantum system carries much more information than usually extracted. The path towards advanced neutron quantum optics will be discussed. (author)
Teaching Statistics Using Classic Psychology Research: An Activities-Based Approach
Holmes, Karen Y.; Dodd, Brett A.
2012-01-01
In this article, we discuss a collection of active learning activities derived from classic psychology studies that illustrate the appropriate use of descriptive and inferential statistics. (Contains 2 tables.)
Bogenschutz, Michael P
2013-03-01
Recent developments in the study of classic hallucinogens, combined with a re-appraisal of the older literature, have led to a renewal of interest in possible therapeutic applications for these drugs, notably their application in the treatment of addictions. This article will first provide a brief review of the research literature providing direct and indirect support for the possible therapeutic effects of classic hallucinogens such as psilocybin and lysergic acid diethylamide (LSD) in the treatment of addictions. Having provided a rationale for clinical investigation in this area, we discuss design issues in clinical trials using classic hallucinogens, some of which are unique to this class of drug. We then discuss the current status of this field of research and design considerations in future randomized trials.
Pre-equilibrium nuclear reactions: An introduction to classical and quantum-mechanical models
International Nuclear Information System (INIS)
Koning, A.J.; Akkermans, J.M.
1999-01-01
In studies of light-ion induced nuclear reactions one distinguishes three different mechanisms: direct, compound and pre-equilibrium nuclear reactions. These reaction processes can be subdivided according to time scales or, equivalently, the number of intranuclear collisions taking place before emission. Furthermore, each mechanism preferably excites certain parts of the nuclear level spectrum and is characterized by different types of angular distributions. This presentation includes description of the classical, exciton model, semi-classical models, with some selected results, and quantum mechanical models. A survey of classical versus quantum-mechanical pre-equilibrium reaction theory is presented including practical applications
Theoretical solid-state physics. From the classical models to modern themes of research. 3. upd. ed.
International Nuclear Information System (INIS)
Czycholl, Gerd
2008-01-01
This book gives an introduction in methods, contents, and results of modern solid-state physics. It is based on the fundamental course of theoretical physics, i. e. presupposed are knowledges in classical mechanics, electrodynamics, and especially quantum mechanics and statistical physics, as they are mediated in the at all German-speaking universities usual course in theoretical physics generally until the end of the 6th special semester. The especially for the treatment of many-body effects unavoidable formalism of the 2nd quantization (occupation number representation) is introduced and used in the book. The content reaches from the classical fields of solid-state physics (phonons and electrons in the periodic potentia, Bloch theorem, Hartree-Fock approximation, electron-phonon interactions) through fields of applications as superconductivity and magnetism until fields, which are actual object of research (for instance quantum Hall effect, high-temperature superconductivity). The third editions was comprehensively revised [de
Atomic collision experiments at the border line between classical and quantum mechanics
International Nuclear Information System (INIS)
Aquilanti, V.
1984-01-01
In order to understand atomic and molecular interactions, one has to learn how to live with the wave-particle duality, considering classical nuclei and quantum electrons. A better way, illustrated by reference to experiments, is by quasiclassical (or semi-classical) mechanics, governing a world with a quasi-zero Planck's constant. One thus explains optical analogs (shadows, rainbows, glories) as interference effects in atomic collisions. Reference is also made to Wheeler's 'black bird' on the inversion problem from spectroscopy and scattering to molecular structure. The paper concludes outlining a journey in the hyperspace to escape from Einstein's torus and to find interferences and resonances in three body scattering and reactions. (Auth.)
International Nuclear Information System (INIS)
Costella, J.P.; McKellar, B.H.J.; Rawlinson, A.A.
1997-03-01
We review how antiparticles may be introduced in classical relativistic mechanics, and emphasize that many of their paradoxical properties can be more transparently understood in the classical than in the quantum domain. (authors)
More Like Jazz than Classical: Reciprocal Interactions among Educational Researchers and Respondents
Dance, L. Janelle; Gutierrez, Rochelle; Hermes, Mary
2010-01-01
In this article, educational scholars L. Janelle Dance, Rochelle Gutierrez, and Mary Hermes share insights from their lived experience as qualitative researchers trying to work in collaboration with diverse populations. They refer to these insights as "improvisations on conventional qualitative methods," reminding readers that their…
Directory of Open Access Journals (Sweden)
Olson Peter D
2010-12-01
Full Text Available Abstract Background Hymenolepis microstoma (Dujardin, 1845 Blanchard, 1891, the mouse bile duct tapeworm, is a rodent/beetle-hosted laboratory model that has been used in research and teaching since its domestication in the 1950s. Recent characterization of its genome has prompted us to describe the specific strain that underpins these data, anchoring its identity and bringing the 150+ year-old original description up-to-date. Results Morphometric and ultrastructural analyses were carried out on laboratory-reared specimens of the 'Nottingham' strain of Hymenolepis microstoma used for genome characterization. A contemporary description of the species is provided including detailed illustration of adult anatomy and elucidation of its taxonomy and the history of the specific laboratory isolate. Conclusions Our work acts to anchor the specific strain from which the H. microstoma genome has been characterized and provides an anatomical reference for researchers needing to employ a model tapeworm system that enables easy access to all stages of the life cycle. We review its classification, life history and development, and briefly discuss the genome and other model systems being employed at the beginning of a genomic era in cestodology.
Nordic Nuclear Safety Research 1994 - 2008: From standardized 4-year classics to customized R and B
International Nuclear Information System (INIS)
Bennerstedt, T.N.O.
2011-10-01
This is a presentation of NKS (Nordic Nuclear Safety Research), its work and achievements in the years 1994 - 2008, during which the author served as Nordic secretary and (later) as coordinator. NKS and the Nordic perspective are briefly introduced together with the NKS support structure, organization and administration: Owners, Board, Nordic secretary, Bureau and Secretariat. The author then embarks on a journey through the modern history of NKS work. The last two of the six fixed 4-year programs are described as regards planning, contents, project work, administration, dissemination of results, evaluations and conclusions. The trip continues to the land of R and B and the present (2011) structure of two general frameworks, namely, NKS-R: reactor safety, and NKS-B: emergency preparedness; each consisting of a set of flexible activities; hence, R and B. The reasoning behind this makeover is touched upon together with the new organization and simpler administration that developed. Major activities and the produced results are introduced and the evaluations summarized. The author's own conclusions and recommendations are followed by a short and subjective list of references. In a number of appendices some important background material has been compiled: bullet point versions of minutes of Owners Group and Board meetings; economic contributions and budgets; the NKS policy document; an overview of all NKS programs and evaluations; lists of R and B activities and funding; the author's personal remarks; a list of some NKS documents (other than technical reports and minutes); and a list of acronyms used in this report. (Author)
Nordic Nuclear Safety Research 1994 - 2008: From standardized 4-year classics to customized R and B
Energy Technology Data Exchange (ETDEWEB)
Bennerstedt, T N.O. [TeknoTelje HB, Torhamn (Sweden)
2011-10-15
This is a presentation of NKS (Nordic Nuclear Safety Research), its work and achievements in the years 1994 - 2008, during which the author served as Nordic secretary and (later) as coordinator. NKS and the Nordic perspective are briefly introduced together with the NKS support structure, organization and administration: Owners, Board, Nordic secretary, Bureau and Secretariat. The author then embarks on a journey through the modern history of NKS work. The last two of the six fixed 4-year programs are described as regards planning, contents, project work, administration, dissemination of results, evaluations and conclusions. The trip continues to the land of R and B and the present (2011) structure of two general frameworks, namely, NKS-R: reactor safety, and NKS-B: emergency preparedness; each consisting of a set of flexible activities; hence, R and B. The reasoning behind this makeover is touched upon together with the new organization and simpler administration that developed. Major activities and the produced results are introduced and the evaluations summarized. The author's own conclusions and recommendations are followed by a short and subjective list of references. In a number of appendices some important background material has been compiled: bullet point versions of minutes of Owners Group and Board meetings; economic contributions and budgets; the NKS policy document; an overview of all NKS programs and evaluations; lists of R and B activities and funding; the author's personal remarks; a list of some NKS documents (other than technical reports and minutes); and a list of acronyms used in this report. (Author)
Li, Guangyan; Wang, Dequn; Fang, Shiying; Xu, Maohong
2014-05-01
Aucklandia lappa Decne was first recorded in the Sheng nong ben cao jing (Shennong's Classic of Materia Medica). Through the textual research of herbal literature, it was found that the costus root in the Sheng nong ben cao jing perhaps was not the plant of Aucklandia lappa Decne of Compositae, but the eaglewood or Lignum Aquilasria Resinatum based on the comprehensive judgment of shape, taste, nature, and function etc. In the Sheng nong ben cao jing, it only includes costus root without the title of eaglewood, and Tao Hongjing recorded both herbs together in his Ming yi bie lu (Supplementary Records of Celebrated Physicians), which became a foreshadow of misunderstanding of the later generations. Beginning from the Tang ben cao (Materia Medica of the Tang Dynasty), the costus root was considered as the plant of Auckiandia lappa Decne from the Compostae with its profound influence until now.
Nordic Nuclear Safety Research 1994 - 2008: From standardized 4-year classics to customized R and B
Energy Technology Data Exchange (ETDEWEB)
Bennerstedt, T.N.O. (TeknoTelje HB, Torhamn (Sweden))
2011-10-15
This is a presentation of NKS (Nordic Nuclear Safety Research), its work and achievements in the years 1994 - 2008, during which the author served as Nordic secretary and (later) as coordinator. NKS and the Nordic perspective are briefly introduced together with the NKS support structure, organization and administration: Owners, Board, Nordic secretary, Bureau and Secretariat. The author then embarks on a journey through the modern history of NKS work. The last two of the six fixed 4-year programs are described as regards planning, contents, project work, administration, dissemination of results, evaluations and conclusions. The trip continues to the land of R and B and the present (2011) structure of two general frameworks, namely, NKS-R: reactor safety, and NKS-B: emergency preparedness; each consisting of a set of flexible activities; hence, R and B. The reasoning behind this makeover is touched upon together with the new organization and simpler administration that developed. Major activities and the produced results are introduced and the evaluations summarized. The author's own conclusions and recommendations are followed by a short and subjective list of references. In a number of appendices some important background material has been compiled: bullet point versions of minutes of Owners Group and Board meetings; economic contributions and budgets; the NKS policy document; an overview of all NKS programs and evaluations; lists of R and B activities and funding; the author's personal remarks; a list of some NKS documents (other than technical reports and minutes); and a list of acronyms used in this report. (Author)
Ligare, Martin
2016-05-01
Multiple-pulse NMR experiments are a powerful tool for the investigation of molecules with coupled nuclear spins. The product operator formalism provides a way to understand the quantum evolution of an ensemble of weakly coupled spins in such experiments using some of the more intuitive concepts of classical physics and semi-classical vector representations. In this paper I present a new way in which to interpret the quantum evolution of an ensemble of spins. I recast the quantum problem in terms of mixtures of pure states of two spins whose expectation values evolve identically to those of classical moments. Pictorial representations of these classically evolving states provide a way to calculate the time evolution of ensembles of weakly coupled spins without the full machinery of quantum mechanics, offering insight to anyone who understands precession of magnetic moments in magnetic fields.
Benacquista, Matthew J
2018-01-01
This textbook provides an introduction to classical mechanics at a level intermediate between the typical undergraduate and advanced graduate level. This text describes the background and tools for use in the fields of modern physics, such as quantum mechanics, astrophysics, particle physics, and relativity. Students who have had basic undergraduate classical mechanics or who have a good understanding of the mathematical methods of physics will benefit from this book.
Mathematical physics classical mechanics
Knauf, Andreas
2018-01-01
As a limit theory of quantum mechanics, classical dynamics comprises a large variety of phenomena, from computable (integrable) to chaotic (mixing) behavior. This book presents the KAM (Kolmogorov-Arnold-Moser) theory and asymptotic completeness in classical scattering. Including a wealth of fascinating examples in physics, it offers not only an excellent selection of basic topics, but also an introduction to a number of current areas of research in the field of classical mechanics. Thanks to the didactic structure and concise appendices, the presentation is self-contained and requires only knowledge of the basic courses in mathematics. The book addresses the needs of graduate and senior undergraduate students in mathematics and physics, and of researchers interested in approaching classical mechanics from a modern point of view.
Classical and quantum chaotic scattering in a muffin tin potential
International Nuclear Information System (INIS)
Brandis, S.
1995-05-01
In this paper, we study the classical mechanics, the quantum mechanics and the semi-classical approximation of the 2-dimensional scattering from a muffin tin potential. The classical dynamical system for Coulombic muffin tins is proven to be chaotic by explicit construction of the exponentially increasing number of periodic orbits. These are all shown to be completely unstable (hyperbolic). By methods of the thermodynamic formalism we can determine the Hausdorff dimension, escape rate and Kolmogorov-Sinai-entropy of the system. An extended KKR-method is developed to determine the quantum mechanical S-matrix. We compare a few integrable scattering examples with the results of the muffin tin scattering. Characteristic features of the spectrum of eigenphases turn out to be the level repulsion and long range rigidity as compared to a completely random spectrum. In the semiclassical analysis we can rederive the regularized Gutzwiller trace formula directly from the exact KKR-determinant to prove that no further terms contribute in the case of the muffin tin potential. The periodic orbit sum allows to draw some qualitative conclusions about the effects of classical chaos on the quantum mechanics. In the context of scaling systems the theory of almost periodic functions is discussed as a possible mathematical foundation for the semiclassical periodic orbit sums. Some results that can be obtained from this analysis are developed in the context of autocorrelation functions and distribution functions for chaotic scattering systems. (orig.)
CERN. Geneva; Franklin, M
2001-01-01
These will be a set of lectures on classic particle physics experiments, with emphasis on how the emasurements are made. I will discuss experiments made to measure the electric charge distribution of particles, to measure the symmetries of the weak decays, to measure the magnetic moment of the muon. As well as experiments performed which discovered new particles or resonances, like the tAU2and the J/Psi. The coverage will be general and should be understandable to someone knowing little particle physics.
International Nuclear Information System (INIS)
Recami, E.
1984-01-01
A review of tachyons, with particular attention to their classical theory, is presented. The extension of Special Relativity to tachyons in two dimensional is first presented, an elegant model-theory which allows a better understanding also of ordinary physics. Then, the results are extended to the four-dimensional case (particular on tachyon mechanics) that can be derived without assuming the existence of Super-luminal reference-frames. Localizability and the unexpected apparent shape of tachyonic objects are discussed, and it is shown (on the basis of tachyon kinematics) how to solve the common causal paradoxes. In connection with General Relativity, particularly the problem of the apparent superluminal expansions in astrophysics is reviewed. The problem (still open) of the extension of relativitic theories to tachyons in four dimensions is tackled, and the electromagnetic theory of tachyons, a topic that can be relevant also for the experimental side, is reviewed. (Author) [pt
George, Judith W.
2009-01-01
The article identifies some key findings in pedagogical research over recent decades, placing them within a framework of logical curriculum development and current practice in quality assurance and enhancement. Throughout, the ideas and comments are related to the practice of teaching classics in university. (Contains 1 figure and 3 notes.)
DEFF Research Database (Denmark)
Brincker, Benedikte
The last book Anthony D. Smith wrote before he died, and which will be published in Spring 2017, has the title Nation and Classical Music. Smith had for a long time been intrigued by the intimate relationship between the nation and classical music. At the most manifest level it involves...... them into their compositions thus challenging the romantic musical style searching for an authentic national musical expression. Against the backdrop of the extensive research carried out by Anthony Smith into the relationship between the nation and classical music, the present paper seeks to add...... cultural centers. In doing this, the paper seeks to unfold how composers channeled musical inspiration embedded in cultural environments that cut across national boundaries into national musical traditions thus catering to specific national audiences. The paper is written as a tribute to a great mentor...
Classical higher-order processes
DEFF Research Database (Denmark)
Montesi, Fabrizio
2017-01-01
Classical Processes (CP) is a calculus where the proof theory of classical linear logic types processes à la Π-calculus, building on a Curry-Howard correspondence between session types and linear propositions. We contribute to this research line by extending CP with process mobility, inspired by ...
Quantum and classical nonlinear dynamics in a microwave cavity
Energy Technology Data Exchange (ETDEWEB)
Meaney, Charles H.; Milburn, Gerard J. [The University of Queensland, Department of Physics, St Lucia, QLD (Australia); Nha, Hyunchul [Texas A and M University at Qatar, Department of Physics, PO Box 23874, Doha (Qatar); Duty, Timothy [The University of New South Wales, Department of Physics, Kensington, NSW (Australia)
2014-12-01
We consider a quarter wave coplanar microwave cavity terminated to ground via a superconducting quantum interference device. By modulating the flux through the loop, the cavity frequency is modulated. The flux is varied at twice the cavity frequency implementing a parametric driving of the cavity field. The cavity field also exhibits a large effective nonlinear susceptibility modelled as an effective Kerr nonlinearity, and is also driven by a detuned linear drive. We show that the semi-classical model corresponding to this system exhibits a fixed point bifurcation at a particular threshold of parametric pumping power. We show the quantum signature of this bifurcation in the dissipative quantum system. We further linearise about the below threshold classical steady state and consider it to act as a bifurcation amplifier, calculating gain and noise spectra for the corresponding small signal regime. Furthermore, we use a phase space technique to analytically solve for the exact quantum steady state. We use this solution to calculate the exact small signal gain of the amplifier. (orig.)
Classical and quantum aspects of topological solitons (using numerical methods)
International Nuclear Information System (INIS)
Weidig, T.
1999-08-01
In Introduction, we review integrable and topological solitons. In Numerical Methods, we describe how to minimise functionals, time-integrate configurations and solve eigenvalue problems. We also present the Simulated Annealing scheme for minimisation in solitonic systems. In Classical Aspects, we analyse the effect of the potential term on the structure of minimal-energy solutions for any topological charge n. The simplest holomorphic baby Skyrme model has no known stable minimal-energy solution for n > 1. The one-vacuum baby Skyrme model possesses non-radially symmetric multi-skyrmions that look like 'skyrmion lattices' formed by skyrmions with n = 2. The two-vacua baby Skyrme model has radially symmetric multi-skyrmions. We implement Simulated Annealing and it works well for higher order terms. We find that the spatial part of the six-derivative term is zero. In Quantum Aspects, we find the first order quantum mass correction for the φ 4 kink using the semi-classical expansion. We derive a trace formula which gives the mass correction by using the eigenmodes and values of the soliton and vacuum perturbations. We show that the zero mode is the most important contribution. We compute the mass correction of φ 4 kink and Sine-Gordon numerically by solving the eigenvalue equations and substituting into the trace formula. (author)
International Nuclear Information System (INIS)
Carson, L.J.
1980-01-01
Quantum chromodynamics (QCD) is currently our only candidate for a theory of strong-interaction dynamics. But the evidence for it is very scanty. Indeed, QCD has only been experimentally verified in its predictions of scaling violation in deep inelastic neutrino scattering. Yet, research continues on QCD because it is based on a beautiful idea, namely the incorporation of observed particle symmetries via local gauge invariance. Nevertheless QCD, a quantum field theory in 3 + 1 dimensions is still without solution. The sheer difficulty in solving the full quantum problem has led some to various approximations, in the hopes of shedding light on the structure of the theory. (orig./FKS)
Piątkowski, Włodzimierz; Skrzypek, Michał
2012-01-01
The cognitive identity of medical sociology has developed in a historical perspective in the context of a specific double frame of reference comprising medicine and general sociology. The purpose of this study is to reconstruct the process of the development of the subdiscipline's research specificity in Poland, drawing attention to the general-sociological context of the conceptualization of basic interpretive and analytical sociomedical categories. In this aspect, the presented study is based on the analysis of Polish sociomedical and general-sociological research published from the early 1960s until 1989. The purpose of the study is also to describe in this perspective the structure of the research field of contemporary Western medical sociology, which was a major point of reference in this process. A look at the chronology of how the scientific identity of medical sociology developed in Poland from a historical perspective shows the gradual balancing-out of the subdiscipline's medical references, typical of the early stage of its development, and manifested in the implementation of research projects for the requirements of doctors, through consistently developed and cultivated connections with general sociology manifested in complementing the knowledge of society with aspects related to health and illness. A sine qua non condition for undertaking this scope of research was to work out strictly sociological formulations of these concepts, which was accomplished as a result of the successful reception of general sociology by the subdiscipline in question. The contemporary understanding of the research field of Polish medical sociology defined by Magdalena Sokołowska and developed as part of the 'school of medical sociology', which she initiated, is characterized by the maintenance of close relations with general sociology (affiliations of sociomedical departments in academic sociological institutions, etc.), and at the same time, by partnership cooperation with
Jin, Rui; Lin, Zhi-jian; Xue, Chun-miao; Zhang, Bing
2013-09-01
Knowledge Discovery in Databases is gaining attention and raising new hopes for traditional Chinese medicine (TCM) researchers. It is a useful tool in understanding and deciphering TCM theories. Aiming for a better understanding of Chinese herbal property theory (CHPT), this paper performed an improved association rule learning to analyze semistructured text in the book entitled Shennong's Classic of Materia Medica. The text was firstly annotated and transformed to well-structured multidimensional data. Subsequently, an Apriori algorithm was employed for producing association rules after the sensitivity analysis of parameters. From the confirmed 120 resulting rules that described the intrinsic relationships between herbal property (qi, flavor and their combinations) and herbal efficacy, two novel fundamental principles underlying CHPT were acquired and further elucidated: (1) the many-to-one mapping of herbal efficacy to herbal property; (2) the nonrandom overlap between the related efficacy of qi and flavor. This work provided an innovative knowledge about CHPT, which would be helpful for its modern research.
Directory of Open Access Journals (Sweden)
Adriana Coutinho de Azevedo Guimarães
2008-06-01
Full Text Available This study aimed to elucidate what injuries are most likely to occur due to classical ballet practice. The research used national and international bibliography. The bibliography analysis indicated that technical and esthetical demands lead to a practice of non-anatomical movements, causing the ballet dancer to suffer from a number of associated lesions. Most of the injuries are caused by technical mistakes and wrong training. Troubles in children are usually due to trying to force external rotation at hip level and to undue use of point ballet slippers. The commonest lesions are in feet and ankles, followed by knees and hips. The rarest ones are in the upper limbs. These injuries are caused by exercise excess, by repetitions always in the same side and by wrong and early use of point slippers. The study reached the conclusion that incorrect application of classical ballet technique predisposes the dancers to characteristic injuries.
Classical dynamics a modern perspective
Sudarshan, Ennackal Chandy George
2016-01-01
Classical dynamics is traditionally treated as an early stage in the development of physics, a stage that has long been superseded by more ambitious theories. Here, in this book, classical dynamics is treated as a subject on its own as well as a research frontier. Incorporating insights gained over the past several decades, the essential principles of classical dynamics are presented, while demonstrating that a number of key results originally considered only in the context of quantum theory and particle physics, have their foundations in classical dynamics.Graduate students in physics and practicing physicists will welcome the present approach to classical dynamics that encompasses systems of particles, free and interacting fields, and coupled systems. Lie groups and Lie algebras are incorporated at a basic level and are used in describing space-time symmetry groups. There is an extensive discussion on constrained systems, Dirac brackets and their geometrical interpretation. The Lie-algebraic description of ...
Zwart, Hub
2015-12-01
In 2003, biophysicist and Nobel Laureate Maurice Wilkins published his autobiography entitled The Third Man. In the preface, he diffidently points out that the title (which presents him as the 'third' man credited with the co-discovery of the structure of DNA, besides Watson and Crick) was chosen by his publisher, as a reference to the famous 1949 movie no doubt, featuring Orson Welles in his classical role as penicillin racketeer Harry Lime. In this paper I intend to show that there is much more to this title than merely its familiar ring. If subjected to a (psychoanalytically inspired) comparative analysis, multiple correspondences between movie and memoirs can be brought to the fore. Taken together, these documents shed an intriguing light on the vicissitudes of budding life sciences research during the post-war era. I will focus my comparative analysis on issues still relevant today, such as dual use, the handling of sensitive scientific information (in a moral setting defined by the tension between collaboration and competition) and, finally, on the interwovenness of science and warfare (i.e. the 'militarisation' of research and the relationship between beauty and destruction). Thus, I will explain how science autobiographies on the one hand and genres of the imagination (such as novels and movies) on the other may deepen our comprehension of tensions and dilemmas of life sciences research then and now. For that reason, science autobiographies can provide valuable input (case material) for teaching philosophy and history of science to science students.
Indian Academy of Sciences (India)
Journal of Genetics, Vol. 85, No. 2, August 2006. 101. Page 2. J. Genet. classic. 102. Journal of Genetics, Vol. 85, No. 2, August 2006. Page 3. J. Genet. classic. Journal of Genetics, Vol. 85, No. 2, August 2006. 103. Page 4. J. Genet. classic. 104. Journal of Genetics, Vol. 85, No. 2, August 2006. Page 5. J. Genet. classic.
Indian Academy of Sciences (India)
Unknown
Journal of Genetics, Vol. 84, No. 1, April 2005. 37. Page 2. J. Genet. classic. Journal of Genetics, Vol. 84, No. 1, April 2005. 38. Page 3. J. Genet. classic. Journal of Genetics, Vol. 84, No. 1, April 2005. 39. Page 4. J. Genet. classic. Journal of Genetics, Vol. 84, No. 1, April 2005. 40. Page 5. J. Genet. classic. Journal of ...
Directory of Open Access Journals (Sweden)
Maryann Wilson
2013-01-01
Full Text Available BACKGROUND: The impact of a scientific article is proportional to the citations it has received. In this study, we set out to identify the most cited works in epileptology in order to evaluate research trends in this field. METHODS: According to the Web of Science database, articles with more than 400 citations qualify as "citation classics". We conducted a literature search on the ISI Web of Science bibliometric database for scientific articles relevant to epilepsy. RESULTS: We retrieved 67 highly cited articles (400 or more citations, which were published in 31 journals: 17 clinical studies, 42 laboratory studies, 5 reviews and 3 classification articles. Clinical studies consisted of epidemiological analyses (n=3, studies on the clinical phenomenology of epilepsy (n=5 – including behavioral and prognostic aspects – and articles focusing on pharmacological (n=6 and non-pharmacological (n=3 treatment. The laboratory studies dealt with genetics (n=6, animal models (n=27, and neurobiology (n=9 – including both neurophysiology and neuropathology studies. The majority (61% of citation classics on epilepsy were published after 1986, possibly reflecting the expansion of research interest in laboratory studies driven by the development of new methodologies, specifically in the fields of genetics and animal models. Consequently, clinical studies were highly cited both before and after the mid 80s, whilst laboratory researches became widely cited after 1990. CONCLUSIONS: Our study indicates that the main drivers of scientific impact in the field of epileptology have increasingly become genetic and neurobiological studies, along with research on animal models of epilepsy. These articles are able to gain the highest numbers of citations in the time span of a few years and suggest potential directions for future research.
Indian Academy of Sciences (India)
Unknown
Journal of Genetics, Vol. 83, No. 3, December 2004. 235. Page 2. J. Genet. classic. Journal of Genetics, Vol. 83, No. 3, December 2004. 236. Page 3. J. Genet. classic. Journal of Genetics, Vol. 83, No. 3, December 2004. 237. Page 4. J. Genet. classic. Journal of Genetics, Vol. 83, No. 3, December 2004. 238. Page 5 ...
Quantum–classical correspondence in chaotic dynamics of laser-driven atoms
International Nuclear Information System (INIS)
Prants, S V
2017-01-01
This paper is a review article on some aspects of quantum–classical correspondence in chaotic dynamics of cold atoms interacting with a standing-wave laser field forming an optical lattice. The problem is treated from both (semi)classical and quantum points of view. In both approaches, the interaction of an atomic electic dipole with the laser field is treated quantum mechanically. Translational motion is described, at first, classically (atoms are considered to be point-like objects) and then quantum mechanically as a propagation of matter waves. Semiclassical equations of motion are shown to be chaotic in the sense of classical dynamical chaos. Point-like atoms in an absolutely deterministic and rigid optical lattice can move in a random-like manner demonstrating a chaotic walking with typical features of classical chaos. This behavior is explained by random-like ‘jumps’ of one of the atomic internal variable when atoms cross nodes of the standing wave and occurs in a specific range of the atom-field detuning. When treating atoms as matter waves, we show that they can make nonadiabatic transitions when crossing the standing-wave nodes. The point is that atomic wave packets split at each node in the same range of the atom-field detuning where the classical chaos occurs. The key point is that the squared amplitude of those semiclassical ‘jumps’ equal to the quantum Landau–Zener parameter which defines the probability of nonadiabatic transitions at the nodes. Nonadiabatic atomic wave packets are much more complicated compared to adiabatic ones and may be called chaotic in this sense. A few possible experiments to observe some manifestations of classical and quantum chaos with cold atoms in horizontal and vertical optical lattices are proposed and discussed. (paper)
International Nuclear Information System (INIS)
Lamb, W.E. Jr.
1981-12-01
This final report describes research on the theory of isotope separation produced by the illumination of polyatomic molecules by intense infrared laser radiation. This process is investigated by treating the molecule, sulfur hexafluoride, as a system of seven classical particles that obey the Newtonian equations of motion. A minicomputer is used to integrate these differential equations. The particles are acted on by interatomic forces, and by the time-dependent electric field of the laser. We have a very satisfactory expression for the interaction of the laser and the molecule which is compatible with infrared absorption and spectroscopic data. The interatomic potential is capable of improvement, and progress on this problem is still being made. We have made several computer runs of the dynamical behavior of the molecule using a reasonably good model for the interatomic force law. For the laser parameters chosen, we find that typically the molecule passes quickly through the resonance region into the quasi-continuum and even well into the real continuum before dissociation actually occurs. When viewed on a display terminal, the motions are exceedingly complex. As an aid to the visualization of the process, we have made a number of 16 mm movies depicting a three-dimensional representation of the motion of the seven particles. These show even more clearly the enormous complexity of the motions, and make clear the desirability of finding ways of characterizing the motion in simple ways without giving all of the numerical detail. One of the ways to do this is to introduce statistical parameters such as a temperature associated with the distribution of kinetic energies of the single particle. We have made such an analysis of our data runs, and have found favorable indications that such methods will prove useful in keeping track of the dynamical histories
Polymer quantization of the free scalar field and its classical limit
Energy Technology Data Exchange (ETDEWEB)
Laddha, Alok; Varadarajan, Madhavan, E-mail: alok@rri.res.i, E-mail: madhavan@rri.res.i [Raman Research Institute, Bangalore 560 080 (India)
2010-09-07
Building on prior work, a generally covariant reformulation of a free scalar field theory on the flat Lorentzian cylinder is quantized using loop quantum gravity (LQG)-type 'polymer' representations. This quantization of the continuum classical theory yields a quantum theory which lives on a discrete spacetime lattice. We explicitly construct a state in the polymer Hilbert space which reproduces the standard Fock vacuum two-point functions for long-wavelength modes of the scalar field. Our construction indicates that the continuum classical theory emerges under coarse graining. All our considerations are free of the 'triangulation' ambiguities which plague attempts to define quantum dynamics in LQG. Our work constitutes the first complete LQG-type quantization of a generally covariant field theory together with a semi-classical analysis of the true degrees of freedom and thus provides a perfect infinite-dimensional toy model to study open issues in LQG, particularly those pertaining to the definition of quantum dynamics.
Classical geometry to quantum behavior correspondence in a virtual extra dimension
International Nuclear Information System (INIS)
Dolce, Donatello
2012-01-01
In the Lorentz invariant formalism of compact space–time dimensions the assumption of periodic boundary conditions represents a consistent semi-classical quantization condition for relativistic fields. In Dolce (2011) we have shown, for instance, that the ordinary Feynman path integral is obtained from the interference between the classical paths with different winding numbers associated with the cyclic dynamics of the field solutions. By means of the boundary conditions, the kinematical information of interactions can be encoded on the relativistic geometrodynamics of the boundary, see Dolce (2012) . Furthermore, such a purely four-dimensional theory is manifestly dual to an extra-dimensional field theory. The resulting correspondence between extra-dimensional geometrodynamics and ordinary quantum behavior can be interpreted in terms of AdS/CFT correspondence. By applying this approach to a simple Quark–Gluon–Plasma freeze-out model we obtain fundamental analogies with basic aspects of AdS/QCD phenomenology. - Highlights: ► Quantum behavior is related to the intrinsic periodicity of isolated systems. ► A periodic phenomenon can be parameterized by a virtual extra dimension. ► KK modes are used to describe the quantum excitations. ► 5D classical geometry encodes 4D quantum behavior. ► Geometrodynamical description of AdS/QCD as modulation of space–time periodicity.
The Zoology of the classical islamic culture
DEFF Research Database (Denmark)
Provencal, Philippe; Aarab, Ahmed
2014-01-01
This article brings a survey of research on the science of zoology in the Classical Arabic/Islamic Culture as revealed in texts on this subject written in Classical Arabic from the second half of the 8th century to the 15th century A.D. In the light of recent research and by use of examples from...
Classical databases and knowledge organization
DEFF Research Database (Denmark)
Hjørland, Birger
2015-01-01
This paper considers classical bibliographic databases based on the Boolean retrieval model (such as MEDLINE and PsycInfo). This model is challenged by modern search engines and information retrieval (IR) researchers, who often consider Boolean retrieval a less efficient approach. The paper...
Principal bundles the classical case
Sontz, Stephen Bruce
2015-01-01
This introductory graduate level text provides a relatively quick path to a special topic in classical differential geometry: principal bundles. While the topic of principal bundles in differential geometry has become classic, even standard, material in the modern graduate mathematics curriculum, the unique approach taken in this text presents the material in a way that is intuitive for both students of mathematics and of physics. The goal of this book is to present important, modern geometric ideas in a form readily accessible to students and researchers in both the physics and mathematics communities, providing each with an understanding and appreciation of the language and ideas of the other.
Classical higher-order processes
DEFF Research Database (Denmark)
Montesi, Fabrizio
2017-01-01
Classical Processes (CP) is a calculus where the proof theory of classical linear logic types processes à la Π-calculus, building on a Curry-Howard correspondence between session types and linear propositions. We contribute to this research line by extending CP with process mobility, inspired...... by the Higher-Order Π-calculus. The key to our calculus is that sequents are asymmetric: one side types sessions as in CP and the other types process variables, which can be instantiated with process values. The controlled interaction between the two sides ensures that process variables can be used at will......, but always respecting the linear usage of sessions expected by the environment....
Classicality in quantum mechanics
International Nuclear Information System (INIS)
Dreyer, Olaf
2007-01-01
In this article we propose a solution to the measurement problem in quantum mechanics. We point out that the measurement problem can be traced to an a priori notion of classicality in the formulation of quantum mechanics. If this notion of classicality is dropped and instead classicality is defined in purely quantum mechanical terms the measurement problem can be avoided. We give such a definition of classicality. It identifies classicality as a property of large quantum system. We show how the probabilistic nature of quantum mechanics is a result of this notion of classicality. We also comment on what the implications of this view are for the search of a quantum theory of gravity
Classicality in quantum mechanics
Energy Technology Data Exchange (ETDEWEB)
Dreyer, Olaf [Theoretical Physics, Blackett Laboratory, Imperial College London, London, SW7 2AZ (United Kingdom)
2007-05-15
In this article we propose a solution to the measurement problem in quantum mechanics. We point out that the measurement problem can be traced to an a priori notion of classicality in the formulation of quantum mechanics. If this notion of classicality is dropped and instead classicality is defined in purely quantum mechanical terms the measurement problem can be avoided. We give such a definition of classicality. It identifies classicality as a property of large quantum system. We show how the probabilistic nature of quantum mechanics is a result of this notion of classicality. We also comment on what the implications of this view are for the search of a quantum theory of gravity.
Kim, Sooyeon; Livingston, Samuel A.
2017-01-01
The purpose of this simulation study was to assess the accuracy of a classical test theory (CTT)-based procedure for estimating the alternate-forms reliability of scores on a multistage test (MST) having 3 stages. We generated item difficulty and discrimination parameters for 10 parallel, nonoverlapping forms of the complete 3-stage test and…
Digital Classics Outside the Echo-Chamber
Bodard, Gabriel; Romanello, Matteo
2016-01-01
This volume, edited by the organizers of the “Digital Classicist” seminars series, presents research in classical studies, digital classics and digital humanities, bringing together scholarship that addresses the impact of the study of classical antiquity through computational methods on audiences such as scientists, heritage professionals, students and the general public. Within this context, chapters tackle particular aspects, from epigraphy, papyrology and manuscripts, via Greek language, ...
Progress report for a research program in theoretical high-energy physics
International Nuclear Information System (INIS)
Feldman, D.
1978-01-01
Last year's research program dealt with a variety of topics including small-p/sub perpendicular/ hadronic phenomenology (dual topological unitarization, Pomeron-f identity hypothesis, t-channel approach to diffraction peak and hadron size, tunneling in Reggeon field theory); bound-state problems in quantum electrodynamics (positronium decay, hyperfine splitting of positronium and muonium); quantum field theory (graph counting, strong-coupling solutions for eikonal problems with SU(2) constraints, unitarity restriction and semi-classical solutions, quark confinement); unified gauge models of weak and electromagnetic interactions (Weinberg-Salam model, exclusion of effective V/sub e/V/sub N/ + A/sub e/A/sub N/ neutral-current interaction, Cabibbo angle and quark mass ratios); bound-state mean field theory (structural equivalence of two-dimensional four-fermion and Yukawa-like models, renormalization of four-dimensional four-fermion models, Fermi theory of weak interactions as a Yang-Mills theory); acoustic detection of cosmic neutrinos; topics in gravitation and cosmology; as well as other studies involving the interactions of elementary particles. A list of publications is included
Classical spins in superconductors
Energy Technology Data Exchange (ETDEWEB)
Shiba, H [Tokyo Univ.; Maki, K
1968-08-01
It is shown that there exists a localized excited state in the energy gap in a superconductor with a classical spin. At finite concentration localized excited states around classical spins form an impurity band. The process of growth of the impurity band and its effects on observable quantities are investigated.
Valley, Lois
1989-01-01
The SPS product, Classic-Ada, is a software tool that supports object-oriented Ada programming with powerful inheritance and dynamic binding. Object Oriented Design (OOD) is an easy, natural development paradigm, but it is not supported by Ada. Following the DOD Ada mandate, SPS developed Classic-Ada to provide a tool which supports OOD and implements code in Ada. It consists of a design language, a code generator and a toolset. As a design language, Classic-Ada supports the object-oriented principles of information hiding, data abstraction, dynamic binding, and inheritance. It also supports natural reuse and incremental development through inheritance, code factoring, and Ada, Classic-Ada, dynamic binding and static binding in the same program. Only nine new constructs were added to Ada to provide object-oriented design capabilities. The Classic-Ada code generator translates user application code into fully compliant, ready-to-run, standard Ada. The Classic-Ada toolset is fully supported by SPS and consists of an object generator, a builder, a dictionary manager, and a reporter. Demonstrations of Classic-Ada and the Classic-Ada Browser were given at the workshop.
Fermions from classical statistics
International Nuclear Information System (INIS)
Wetterich, C.
2010-01-01
We describe fermions in terms of a classical statistical ensemble. The states τ of this ensemble are characterized by a sequence of values one or zero or a corresponding set of two-level observables. Every classical probability distribution can be associated to a quantum state for fermions. If the time evolution of the classical probabilities p τ amounts to a rotation of the wave function q τ (t)=±√(p τ (t)), we infer the unitary time evolution of a quantum system of fermions according to a Schroedinger equation. We establish how such classical statistical ensembles can be mapped to Grassmann functional integrals. Quantum field theories for fermions arise for a suitable time evolution of classical probabilities for generalized Ising models.
CLASSICAL AND NON-CLASSICAL PHILOSOPHICAL ANTHROPOLOGY: COMPARATIVE ANALYSIS
Directory of Open Access Journals (Sweden)
T. A. Kozlova
2018-01-01
Full Text Available Introduction: The goals and values of human life, the search for the meaning of human existence contain the potential for a meaningful, progressive development of philosophical and anthropological ideas at any time in history. One of the tasks of philosophical anthropology is the formation of the image of man, the choice of ways to achieve the ideal, the methods of comprehension and resolution of universal problems. The increasing processes of differentiation in science led to the formation of different views on the nature of man, to the distinction between classical and non-classical philosophical anthropology. А comparative analysis of these trends is given in this article.Materials and methods: The dialectical method is preferred in the question of research methodology, the hermeneutic and phenomenological approaches are used.Results: The development of philosophical anthropology correlates with the challenges of modernity. By tracking the trends of human change, philosophical anthropology changes the approach to the consideration of its main subject of research. The whole array of disciplines that study man comes to new discoveries, new theories, and philosophical anthropology changes its view of the vision, challenging the principles of classical philosophical anthropology.Classical philosophical anthropology elevates the biological nature of man to a pedestal, non-classical philosophical anthropology actualizes questions of language, culture, thinking, understanding, actualizes the hermeneutic and phenomenological approaches. The desire to understand a person in classical philosophical anthropology is based on the desire to fully reveal the biological mechanisms in a person. The perspective of treating a person in nonclassical philosophical anthropology is polyformen: man as a text, as a dreaming self, as an eternal transition. Non-classical philosophical anthropology, goes from the idea of identity to the idea of variability, from
Supersymmetric classical mechanics
International Nuclear Information System (INIS)
Biswas, S.N.; Soni, S.K.
1986-01-01
The purpose of the paper is to construct a supersymmetric Lagrangian within the framework of classical mechanics which would be regarded as a candidate for passage to supersymmetric quantum mechanics. 5 refs. (author)
THE BUREAUCRATIC PHENOMENON: CLASSICAL CONCEPTS
Дама Ибрагима
2013-01-01
Aim of this article - to analyze Hegel and Karl Marx’s classic bureaucracy theories and also Max Weber’s concept of rational bureaucracy and its development in the works of Herbert Simon, Robert Merton, Peter Blau and Michel Crozier. It shows that the above listed researchers only undertook a change of terminology within the same theoretical tradition. The article describes different approaches to the bureaucratic system of administrative schools of the late 1950s and early 1980s. Major concl...
From classical to quantum mechanics: ``How to translate physical ideas into mathematical language''
Bergeron, H.
2001-09-01
principle). Moreover spins for particles are naturally generated, including an approximation of their interaction with magnetic fields. We also recover by this approach the semi-classical formalism developed by E. Prugovečki [Stochastic Quantum Mechanics and Quantum Space-time (Reidel, Dordrecht, 1986)].
Chaos, scaling and existence of a continuum limit in classical non-Abelian lattice gauge theory
International Nuclear Information System (INIS)
Nielsen, H.B.; Rugh, H.H.; Rugh, S.E.
1996-01-01
We discuss space-time chaos and scaling properties for classical non-Abelian gauge fields discretized on a spatial lattice. We emphasize that there is a open-quote no goclose quotes for simulating the original continuum classical gauge fields over a long time span since there is a never ending dynamical cascading towards the ultraviolet. We note that the temporal chaotic properties of the original continuum gauge fields and the lattice gauge system have entirely different scaling properties thereby emphasizing that they are entirely different dynamical systems which have only very little in common. Considered as a statistical system in its own right the lattice gauge system in a situation where it has reached equilibrium comes closest to what could be termed a open-quotes continuum limitclose quotes in the limit of very small energies (weak non-linearities). We discuss the lattice system both in the limit for small energies and in the limit of high energies where we show that there is a saturation of the temporal chaos as a pure lattice artifact. Our discussion focuses not only on the temporal correlations but to a large extent also on the spatial correlations in the lattice system. We argue that various conclusions of physics have been based on monitoring the non-Abelian lattice system in regimes where the fields are correlated over few lattice units only. This is further evidenced by comparison with results for Abelian lattice gauge theory. How the real time simulations of the classical lattice gauge theory may reach contact with the real time evolution of (semi-classical aspects of) the quantum gauge theory (e.g. Q.C.D.) is left an important question to be further examined
Classical and multilinear harmonic analysis
Muscalu, Camil
2013-01-01
This two-volume text in harmonic analysis introduces a wealth of analytical results and techniques. It is largely self-contained and useful to graduates and researchers in pure and applied analysis. Numerous exercises and problems make the text suitable for self-study and the classroom alike. The first volume starts with classical one-dimensional topics: Fourier series; harmonic functions; Hilbert transform. Then the higher-dimensional Calderón-Zygmund and Littlewood-Paley theories are developed. Probabilistic methods and their applications are discussed, as are applications of harmonic analysis to partial differential equations. The volume concludes with an introduction to the Weyl calculus. The second volume goes beyond the classical to the highly contemporary and focuses on multilinear aspects of harmonic analysis: the bilinear Hilbert transform; Coifman-Meyer theory; Carleson's resolution of the Lusin conjecture; Calderón's commutators and the Cauchy integral on Lipschitz curves. The material in this vo...
Twisted classical Poincare algebras
International Nuclear Information System (INIS)
Lukierski, J.; Ruegg, H.; Tolstoy, V.N.; Nowicki, A.
1993-11-01
We consider the twisting of Hopf structure for classical enveloping algebra U(g), where g is the inhomogeneous rotations algebra, with explicite formulae given for D=4 Poincare algebra (g=P 4 ). The comultiplications of twisted U F (P 4 ) are obtained by conjugating primitive classical coproducts by F element of U(c)xU(c), where c denotes any Abelian subalgebra of P 4 , and the universal R-matrices for U F (P 4 ) are triangular. As an example we show that the quantum deformation of Poincare algebra recently proposed by Chaichian and Demiczev is a twisted classical Poincare algebra. The interpretation of twisted Poincare algebra as describing relativistic symmetries with clustered 2-particle states is proposed. (orig.)
Classical mechanics with Maxima
Timberlake, Todd Keene
2016-01-01
This book guides undergraduate students in the use of Maxima—a computer algebra system—in solving problems in classical mechanics. It functions well as a supplement to a typical classical mechanics textbook. When it comes to problems that are too difficult to solve by hand, computer algebra systems that can perform symbolic mathematical manipulations are a valuable tool. Maxima is particularly attractive in that it is open-source, multiple-platform software that students can download and install free of charge. Lessons learned and capabilities developed using Maxima are easily transferred to other, proprietary software.
Iselin, F Christoph
1996-01-01
Exchange of data and algorithms among accelerator physics programs is difficult because of unnecessary differences in input formats and internal data structures. To alleviate these problems a C++ class library called CLASSIC (Clas Library for Accelerator System Simulation and Control) is being developed with the goal to provide standard building blocks for computer programs used in accelerator lattice structures in computer memory using a standard input language, a graphical user interface, or a programmed algorithm. It also provides simulation algorithms. These can easily be replaced by modules which communicate with the control system of the accelerator. Exchange of both data and algorithm between different programs using the CLASSIC library should present no difficulty.
Learning Classical Music Club
2010-01-01
There is a new CERN Club called “Learning Classical Music at CERN”. We are aiming to give classical music lessons for different instruments (see link) for students from 5 to 100 years old. We are now ready to start our activities in the CERN barracks. We are now in the enrollment phase and hope to start lessons very soon ! Club info can be found in the list of CERN Club: http://user.web.cern.ch/user/Communication/SocialLifeActivities/Clubs/Clubs.html Salvatore Buontempo Club President
International Nuclear Information System (INIS)
Starrfield, S.G.
1988-01-01
The classical nova outburst occurs on the white dwarf component in a close binary system. Nova systems are members of the general class of cataclysmic variables and other members of the class are the Dwarf Novae, AM Her variables, Intermediate Polars, Recurrent Novae, and some of the Symbiotic variables. Although multiwavelength observations have already provided important information about all of these systems, in this review I will concentrate on the outbursts of the classical and recurrent novae and refer to other members of the class only when necessary. 140 refs., 1 tab
Elementary classical hydrodynamics
Chirgwin, B H; Langford, W J; Maxwell, E A; Plumpton, C
1967-01-01
Elementary Classical Hydrodynamics deals with the fundamental principles of elementary classical hydrodynamics, with emphasis on the mechanics of inviscid fluids. Topics covered by this book include direct use of the equations of hydrodynamics, potential flows, two-dimensional fluid motion, waves in liquids, and compressible flows. Some general theorems such as Bernoulli's equation are also considered. This book is comprised of six chapters and begins by introducing the reader to the fundamental principles of fluid hydrodynamics, with emphasis on ways of studying the motion of a fluid. Basic c
Classic Problems of Probability
Gorroochurn, Prakash
2012-01-01
"A great book, one that I will certainly add to my personal library."—Paul J. Nahin, Professor Emeritus of Electrical Engineering, University of New Hampshire Classic Problems of Probability presents a lively account of the most intriguing aspects of statistics. The book features a large collection of more than thirty classic probability problems which have been carefully selected for their interesting history, the way they have shaped the field, and their counterintuitive nature. From Cardano's 1564 Games of Chance to Jacob Bernoulli's 1713 Golden Theorem to Parrondo's 1996 Perplexin
Classical electromagnetic radiation
Heald, Mark A
2012-01-01
Newly corrected, this highly acclaimed text is suitable for advanced physics courses. The author presents a very accessible macroscopic view of classical electromagnetics that emphasizes integrating electromagnetic theory with physical optics. The survey follows the historical development of physics, culminating in the use of four-vector relativity to fully integrate electricity with magnetism.
Classical solutions in supergravity
International Nuclear Information System (INIS)
Baaklini, N.S.; Ferrara, S.; Nieuwenhuizen Van, P.
1977-06-01
Classical solutions of supergravity are obtained by making finite global supersymmetry rotation on known solutions of the field equations of the bosonic sector. The Schwarzschild and the Reissner-Nordstoem solutions of general relativity are extended to various supergravity systems and the modification to the perihelion precession of planets is discussed
Huddleston, Gregory H.
1993-01-01
Describes one teacher's methods for introducing to secondary English students the concepts of Classicism and Romanticism in relation to pictures of gardens, architecture, music, and literary works. Outlines how the unit leads to a writing assignment based on collected responses over time. (HB)
Classical Mythology. Fourth Edition.
Morford, Mark P. O.; Lenardon, Robert J.
Designed for students with little or no background in classical literature, this book introduces the Greek and Roman myths of creation, myths of the gods, Greek sagas and local legends, and presents contemporary theories about the myths. Drawing on Homer, Hesiod, Pindar, Vergil, and others, the book provides many translations and paraphrases of…
Tighe, Mary Ann; Avinger, Charles
1994-01-01
Describes young adult novels that may prove to be classics of the genre. Discusses "The "Chocolate War" by Robert Cormier, "The Outsiders" by S. E. Hinton, "The Witch of Blackbird Pond" by Elizabeth George Speare, and "On Fortune's Wheel" by Cynthia Voight. (HB)
Why Study Classical Languages?
Lieberman, Samuel
This speech emphasizes the significance of living literatures and living cultures which owe a direct debt to the Romans and the Greeks from whom they can trace their origins. After commenting on typical rejoinders to the question "Why study classical languages?" and poking fun at those who advance jaded, esoteric responses, the author dispels the…
Expert Western Classical Music Improvisers' Strategies
Despres, JP; Burnard, Pamela Anne; Dube, F; Stevance, S
2017-01-01
The growing interest in musical improvisation is exemplified by the body of literatures evidencing the positive impacts of improvisation learning on the musical apprentice’s aptitudes and the increasing presence of improvisation in Western classical concert halls and competitions. However, high-level Western classical music improvisers’ thinking processes are not yet thoroughly documented. As a result of this gap, our research addresses the following question: What strategies are implement...
Franklin, Joel
2017-01-01
Classical field theory, which concerns the generation and interaction of fields, is a logical precursor to quantum field theory, and can be used to describe phenomena such as gravity and electromagnetism. Written for advanced undergraduates, and appropriate for graduate level classes, this book provides a comprehensive introduction to field theories, with a focus on their relativistic structural elements. Such structural notions enable a deeper understanding of Maxwell's equations, which lie at the heart of electromagnetism, and can also be applied to modern variants such as Chern–Simons and Born–Infeld. The structure of field theories and their physical predictions are illustrated with compelling examples, making this book perfect as a text in a dedicated field theory course, for self-study, or as a reference for those interested in classical field theory, advanced electromagnetism, or general relativity. Demonstrating a modern approach to model building, this text is also ideal for students of theoretic...
International Nuclear Information System (INIS)
Iselin, F. Christoph
1997-01-01
Exchange of data and algorithms among accelerator physics programs is difficult because of unnecessary differences in input formats and internal data structures. To alleviate these problems a C++ class library called CLASSIC (Class Library for Accelerator System Simulation and Control) is being developed with the goal to provide standard building blocks for computer programs used in accelerator design. It includes modules for building accelerator lattice structures in computer memory using a standard input language, a graphical user interface, or a programmed algorithm. It also provides simulation algorithms. These can easily be replaced by modules which communicate with the control system of the accelerator. Exchange of both data and algorithm between different programs using the CLASSIC library should present no difficulty
Classical Diophantine equations
1993-01-01
The author had initiated a revision and translation of "Classical Diophantine Equations" prior to his death. Given the rapid advances in transcendence theory and diophantine approximation over recent years, one might fear that the present work, originally published in Russian in 1982, is mostly superseded. That is not so. A certain amount of updating had been prepared by the author himself before his untimely death. Some further revision was prepared by close colleagues. The first seven chapters provide a detailed, virtually exhaustive, discussion of the theory of lower bounds for linear forms in the logarithms of algebraic numbers and its applications to obtaining upper bounds for solutions to the eponymous classical diophantine equations. The detail may seem stark--- the author fears that the reader may react much as does the tourist on first seeing the centre Pompidou; notwithstanding that, Sprind zuk maintainsa pleasant and chatty approach, full of wise and interesting remarks. His emphases well warrant, ...
Classical and statistical thermodynamics
Rizk, Hanna A
2016-01-01
This is a text book of thermodynamics for the student who seeks thorough training in science or engineering. Systematic and thorough treatment of the fundamental principles rather than presenting the large mass of facts has been stressed. The book includes some of the historical and humanistic background of thermodynamics, but without affecting the continuity of the analytical treatment. For a clearer and more profound understanding of thermodynamics this book is highly recommended. In this respect, the author believes that a sound grounding in classical thermodynamics is an essential prerequisite for the understanding of statistical thermodynamics. Such a book comprising the two wide branches of thermodynamics is in fact unprecedented. Being a written work dealing systematically with the two main branches of thermodynamics, namely classical thermodynamics and statistical thermodynamics, together with some important indexes under only one cover, this treatise is so eminently useful.
Classical and non-classical effective medium theories: New perspectives
Energy Technology Data Exchange (ETDEWEB)
Tsukerman, Igor, E-mail: igor@uakron.edu
2017-05-18
Highlights: • Advanced non-asymptotic and nonlocal homogenization theories of metamaterials, valid in electrostatics and electrodynamics. • Classical theories (Clausius–Mossotti, Lorenz–Lorentz, Maxwell Garnett) fit well into the proposed framework. • Nonlocal effects can be included in the model, making order-of-magnitude accuracy improvements possible. • A challenging problem for future research is to determine what effective tensors are attainable for given constituents of a metamaterial. - Abstract: Future research in electrodynamics of periodic electromagnetic composites (metamaterials) can be expected to produce sophisticated homogenization theories valid for any composition and size of the lattice cell. The paper outlines a promising path in that direction, leading to non-asymptotic and nonlocal homogenization models, and highlights aspects of homogenization that are often overlooked: the finite size of the sample and the role of interface boundaries. Classical theories (e.g. Clausius–Mossotti, Maxwell Garnett), while originally derived from a very different set of ideas, fit well into the proposed framework. Nonlocal effects can be included in the model, making an order-of-magnitude accuracy improvements possible. One future challenge is to determine what effective parameters can or cannot be obtained for a given set of constituents of a metamaterial lattice cell, thereby delineating the possible from the impossible in metamaterial design.
Classical and non-classical effective medium theories: New perspectives
International Nuclear Information System (INIS)
Tsukerman, Igor
2017-01-01
Highlights: • Advanced non-asymptotic and nonlocal homogenization theories of metamaterials, valid in electrostatics and electrodynamics. • Classical theories (Clausius–Mossotti, Lorenz–Lorentz, Maxwell Garnett) fit well into the proposed framework. • Nonlocal effects can be included in the model, making order-of-magnitude accuracy improvements possible. • A challenging problem for future research is to determine what effective tensors are attainable for given constituents of a metamaterial. - Abstract: Future research in electrodynamics of periodic electromagnetic composites (metamaterials) can be expected to produce sophisticated homogenization theories valid for any composition and size of the lattice cell. The paper outlines a promising path in that direction, leading to non-asymptotic and nonlocal homogenization models, and highlights aspects of homogenization that are often overlooked: the finite size of the sample and the role of interface boundaries. Classical theories (e.g. Clausius–Mossotti, Maxwell Garnett), while originally derived from a very different set of ideas, fit well into the proposed framework. Nonlocal effects can be included in the model, making an order-of-magnitude accuracy improvements possible. One future challenge is to determine what effective parameters can or cannot be obtained for a given set of constituents of a metamaterial lattice cell, thereby delineating the possible from the impossible in metamaterial design.
Invitation to classical analysis
Duren, Peter
2012-01-01
This book gives a rigorous treatment of selected topics in classical analysis, with many applications and examples. The exposition is at the undergraduate level, building on basic principles of advanced calculus without appeal to more sophisticated techniques of complex analysis and Lebesgue integration. Among the topics covered are Fourier series and integrals, approximation theory, Stirling's formula, the gamma function, Bernoulli numbers and polynomials, the Riemann zeta function, Tauberian theorems, elliptic integrals, ramifications of the Cantor set, and a theoretical discussion of differ
Strong, John
1958-01-01
An intermediate course in optics, this volume explores both experimental and theoretical concepts, offering practical knowledge of geometrical optics that will enhance students' comprehension of any relevant applied science. Its exposition of the concepts of classical optics is presented with a minimum of mathematical detail but presumes some knowledge of calculus, vectors, and complex numbers.Subjects include light as wave motion; superposition of wave motions; electromagnetic waves; interaction of light and matter; velocities and scattering of light; polarized light and dielectric boundarie
Generalized classical mechanics
International Nuclear Information System (INIS)
De Leon, M.; Rodrigues, P.R.
1985-01-01
The geometrical study of Classical Mechanics shows that the Hamiltonian (respectively, Lagrangian) formalism may be characterized by intrinsical structures canonically defined on the cotangent (respectively, tangent) bundle of a differentiable manifold. A generalized formalism for higher order Lagrangians is developed. Then the Hamiltonian form of the theory is developed. Finally, the Poisson brackets are defined and the conditions under which a mapping is a canonical transformation are studied. The Hamilton-Jacobi equation for this type of mechanics is established. (Auth.)
Classical Weyl transverse gravity
Energy Technology Data Exchange (ETDEWEB)
Oda, Ichiro [University of the Ryukyus, Department of Physics, Faculty of Science, Nishihara, Okinawa (Japan)
2017-05-15
We study various classical aspects of the Weyl transverse (WTDiff) gravity in a general space-time dimension. First of all, we clarify a classical equivalence among three kinds of gravitational theories, those are, the conformally invariant scalar tensor gravity, Einstein's general relativity and the WTDiff gravity via the gauge-fixing procedure. Secondly, we show that in the WTDiff gravity the cosmological constant is a mere integration constant as in unimodular gravity, but it does not receive any radiative corrections unlike the unimodular gravity. A key point in this proof is to construct a covariantly conserved energy-momentum tensor, which is achieved on the basis of this equivalence relation. Thirdly, we demonstrate that the Noether current for the Weyl transformation is identically vanishing, thereby implying that the Weyl symmetry existing in both the conformally invariant scalar tensor gravity and the WTDiff gravity is a ''fake'' symmetry. We find it possible to extend this proof to all matter fields, i.e. the Weyl-invariant scalar, vector and spinor fields. Fourthly, it is explicitly shown that in the WTDiff gravity the Schwarzschild black hole metric and a charged black hole one are classical solutions to the equations of motion only when they are expressed in the Cartesian coordinate system. Finally, we consider the Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmology and provide some exact solutions. (orig.)
Classical algebraic chromodynamics
International Nuclear Information System (INIS)
Adler, S.L.
1978-01-01
I develop an extension of the usual equations of SU(n) chromodynamics which permits the consistent introduction of classical, noncommuting quark source charges. The extension involves adding a singlet gluon, giving a U(n) -based theory with outer product P/sup a/(u,v) = (1/2)(d/sup a/bc + if/sup a/bc)(u/sup b/v/sup c/ - v/sup b/u/sup c/) which obeys the Jacobi identity, inner product S (u,v) = (1/2)(u/sup a/v/sup a/ + v/sup a/u/sup a/), and with the n 2 gluon fields elevated to algebraic fields over the quark color charge C* algebra. I show that provided the color charge algebra satisfies the condition S (P (u,v),w) = S (u,P (v,w)) for all elements u,v,w of the algebra, all the standard derivations of Lagrangian chromodynamics continue to hold in the algebraic chromodynamics case. I analyze in detail the color charge algebra in the two-particle (qq, qq-bar, q-barq-bar) case and show that the above consistency condition is satisfied for the following unique (and, interestingly, asymmetric) choice of quark and antiquark charges: Q/sup a//sub q/ = xi/sup a/, Q/sup a//sub q/ = xi-bar/sup a/ + delta/sup a/0(n/2)/sup 3/2/1, with xi/sup a/xi/sup b/ = (1/2)(d/sup a/bc + if/sup a/bc) xi/sup c/, xi-bar/sup a/xi-bar/sup b/ = -(1/2)(d/sup a/bc - if/sup a/bc) xi-bar/sup c/. The algebraic structure of the two-particle U(n) force problem, when expressed on an appropriately diagonalized basis, leads for all n to a classical dynamics problem involving an ordinary SU(2) Yang-Mills field with uniquely specified classical source charges which are nonparallel in the color-singlet state. An explicit calculation shows that local algebraic U(n) gauge transformations lead only to a rigid global rotation of axes in the overlying classical SU(2) problem, which implies that the relative orientations of the classical source charges have physical significance
van der Heijden, E.H.M.; van der Heijden, M.A.; Roosmalen, van J.; Verdonschot, S.; Kroesen, G.M.W.; Nijdam, S.
2008-01-01
This document represents the results of a year of research as part of the Honors Program of Eindhoven University of Technology. We heard about Randell L. Mills abandoning Quantum Mechanics and proposing an alternative theory. This sounded interesting enough to contact Gerrit M.W. Kroesen whose group
Quantum machine learning: a classical perspective.
Ciliberto, Carlo; Herbster, Mark; Ialongo, Alessandro Davide; Pontil, Massimiliano; Rocchetto, Andrea; Severini, Simone; Wossnig, Leonard
2018-01-01
Recently, increased computational power and data availability, as well as algorithmic advances, have led machine learning (ML) techniques to impressive results in regression, classification, data generation and reinforcement learning tasks. Despite these successes, the proximity to the physical limits of chip fabrication alongside the increasing size of datasets is motivating a growing number of researchers to explore the possibility of harnessing the power of quantum computation to speed up classical ML algorithms. Here we review the literature in quantum ML and discuss perspectives for a mixed readership of classical ML and quantum computation experts. Particular emphasis will be placed on clarifying the limitations of quantum algorithms, how they compare with their best classical counterparts and why quantum resources are expected to provide advantages for learning problems. Learning in the presence of noise and certain computationally hard problems in ML are identified as promising directions for the field. Practical questions, such as how to upload classical data into quantum form, will also be addressed.
Progress in classical and quantum variational principles
International Nuclear Information System (INIS)
Gray, C G; Karl, G; Novikov, V A
2004-01-01
We review the development and practical uses of a generalized Maupertuis least action principle in classical mechanics in which the action is varied under the constraint of fixed mean energy for the trial trajectory. The original Maupertuis (Euler-Lagrange) principle constrains the energy at every point along the trajectory. The generalized Maupertuis principle is equivalent to Hamilton's principle. Reciprocal principles are also derived for both the generalized Maupertuis and the Hamilton principles. The reciprocal Maupertuis principle is the classical limit of Schroedinger's variational principle of wave mechanics and is also very useful to solve practical problems in both classical and semiclassical mechanics, in complete analogy with the quantum Rayleigh-Ritz method. Classical, semiclassical and quantum variational calculations are carried out for a number of systems, and the results are compared. Pedagogical as well as research problems are used as examples, which include nonconservative as well as relativistic systems. '... the most beautiful and important discovery of Mechanics.' Lagrange to Maupertuis (November 1756)
Quantum machine learning: a classical perspective
Ciliberto, Carlo; Herbster, Mark; Ialongo, Alessandro Davide; Pontil, Massimiliano; Rocchetto, Andrea; Severini, Simone; Wossnig, Leonard
2018-01-01
Recently, increased computational power and data availability, as well as algorithmic advances, have led machine learning (ML) techniques to impressive results in regression, classification, data generation and reinforcement learning tasks. Despite these successes, the proximity to the physical limits of chip fabrication alongside the increasing size of datasets is motivating a growing number of researchers to explore the possibility of harnessing the power of quantum computation to speed up classical ML algorithms. Here we review the literature in quantum ML and discuss perspectives for a mixed readership of classical ML and quantum computation experts. Particular emphasis will be placed on clarifying the limitations of quantum algorithms, how they compare with their best classical counterparts and why quantum resources are expected to provide advantages for learning problems. Learning in the presence of noise and certain computationally hard problems in ML are identified as promising directions for the field. Practical questions, such as how to upload classical data into quantum form, will also be addressed.
Directory of Open Access Journals (Sweden)
Laurent Chusseau
2013-02-01
Full Text Available We show that the thermodynamics of ideal gases may be derived solely from the Democritean concept of corpuscles moving in vacuum plus a principle of simplicity, namely that these laws are independent of the laws of motion, aside from the law of energy conservation. Only a single corpuscle in contact with a heat bath submitted to a z and t-invariant force is considered. Most of the end results are known but the method appears to be novel. The mathematics being elementary, the present paper should facilitate the understanding of the ideal gas law and of classical thermodynamics even though not-usually-taught concepts are being introduced.
Institute of Scientific and Technical Information of China (English)
2002-01-01
FIVE years ago, an ancient Chinese air was beamed to outer space as a PR exercise. To humankind, music is a universal language, so the tune seemed an ideal medium for communication with extraterrestrial intelligence. So far there has been no response, but it is believed that the tune will play for a billion years, and eventually be heard and understood. The melody is called High Mountain and Flowing Stream, and it is played on the guqin, a seven-stringed classical musical instrument similar to the zither.
Pollock, Steven
2013-04-01
At most universities, including the University of Colorado, upper-division physics courses are taught using a traditional lecture approach that does not make use of many of the instructional techniques that have been found to improve student learning at the introductory level. We are transforming several upper-division courses using principles of active engagement and learning theory, guided by the results of observations, interviews, and analysis of student work at CU and elsewhere. In this talk I outline these transformations, including the development of faculty consensus learning goals, clicker questions, tutorials, modified homeworks, and more. We present evidence of the effectiveness of these transformations relative to traditional courses, based on student grades, interviews, and through research-based assessments of student conceptual mastery and student attitudes. Our results suggest that many of the tools that have been effective in introductory courses are effective for our majors, and that further research is warranted in the upper-division environment. (See www.colorado.edu/sei/departments/physics.htm for materials)
Directory of Open Access Journals (Sweden)
Hong-Wen Yuan
2013-01-01
Full Text Available Although it is difficult in fully clarifying its mechanisms and effects, Deqi still can be considered as an instant “sign” of acupuncture response of the patient and acupuncturist, which has a significant value in clinic and research. This paper aims to take a history trace to the development of Deqi theory, understand the connotation of Deqi based on Chinese medicine theory, and establish an evaluation methodology accordingly. We believe that Deqi is not only the needling sensation, but also the perception of changes of qi' flowing of the patient elicited by needling on acupoints. The signs of Deqi include the patient’s subjective perception (needling sensation, the objective physiological changes (common referred to the skin redness around the acupoints and the response of brain, and the acupuncturists' perception. Although Deqi is essential for attaining the effect, it may not be the necessary sign of the ideal efficacy. It is found that the characteristics of Deqi sensations, Deqi’s intensity, time duration, and the propagation will all affect the efficacy. Thus, acupuncturists should pay attention to elicit and control Deqi state, which is also the key point in modern research on the therapeutic implications of Deqi.
Jinzenji, Masao
2018-01-01
This book furnishes a brief introduction to classical mirror symmetry, a term that denotes the process of computing Gromov–Witten invariants of a Calabi–Yau threefold by using the Picard–Fuchs differential equation of period integrals of its mirror Calabi–Yau threefold. The book concentrates on the best-known example, the quintic hypersurface in 4-dimensional projective space, and its mirror manifold. First, there is a brief review of the process of discovery of mirror symmetry and the striking result proposed in the celebrated paper by Candelas and his collaborators. Next, some elementary results of complex manifolds and Chern classes needed for study of mirror symmetry are explained. Then the topological sigma models, the A-model and the B-model, are introduced. The classical mirror symmetry hypothesis is explained as the equivalence between the correlation function of the A-model of a quintic hyper-surface and that of the B-model of its mirror manifold. On the B-model side, the process of construct...
Friedmann-Bette, B
2008-08-01
For more than 40 years, the effects of classical altitude training on sea-level performance have been the subject of many scientific investigations in individual endurance sports. To our knowledge, no studies have been performed in team sports like football. Two well-controlled studies showed that living and training at an altitude of >or=1800-2700 m for 3-4 weeks is superior to equivalent training at sea level in well-trained athletes. Most of the controlled studies with elite athletes did not reveal such an effect. However, the results of some uncontrolled studies indicate that sea-level performance might be enhanced after altitude training also in elite athletes. Whether hypoxia provides an additional stimulus for muscular adaptation, when training is performed with equal intensity compared with sea-level training is not known. There is some evidence for an augmentation of total hemoglobin mass after classical altitude training with duration >or=3 weeks at an altitude >or=2000 m due to altitude acclimatization. Considerable individual variation is observed in the erythropoietic response to hypoxia and in the hypoxia-induced reduction of aerobic performance capacity during training at altitude, both of which are thought to contribute to inter-individual variation in the improvement of sea-level performance after altitude training.
International Nuclear Information System (INIS)
Barra, F.; Gaspard, P.
2001-01-01
We consider the classical evolution of a particle on a graph by using a time-continuous Frobenius-Perron operator that generalizes previous propositions. In this way, the relaxation rates as well as the chaotic properties can be defined for the time-continuous classical dynamics on graphs. These properties are given as the zeros of some periodic-orbit zeta functions. We consider in detail the case of infinite periodic graphs where the particle undergoes a diffusion process. The infinite spatial extension is taken into account by Fourier transforms that decompose the observables and probability densities into sectors corresponding to different values of the wave number. The hydrodynamic modes of diffusion are studied by an eigenvalue problem of a Frobenius-Perron operator corresponding to a given sector. The diffusion coefficient is obtained from the hydrodynamic modes of diffusion and has the Green-Kubo form. Moreover, we study finite but large open graphs that converge to the infinite periodic graph when their size goes to infinity. The lifetime of the particle on the open graph is shown to correspond to the lifetime of a system that undergoes a diffusion process before it escapes
Mitev, Ariel Zoltán
2012-01-01
A grounded theory olyan kutatási módszer, ahol az elmélet az empirikus adatokból fejlődik ki és abban gyökerezik (Glaser - Strauss, 1967). Annak ellenére, hogy a módszer nemzetközileg rendkívül népszerű, a grounded theory nem igazán vert gyökeret a hazai menedzsment- és marketingkutatás talajában. A cikk célja a grounded theory kulcsfontosságú mozzanatainak bemutatása és a módszer népszerűsítése. / === / Grounded theory is a research method in which theory emerges from the data and is grounde...
Classical Trajectories and Quantum Spectra
Mielnik, Bogdan; Reyes, Marco A.
1996-01-01
A classical model of the Schrodinger's wave packet is considered. The problem of finding the energy levels corresponds to a classical manipulation game. It leads to an approximate but non-perturbative method of finding the eigenvalues, exploring the bifurcations of classical trajectories. The role of squeezing turns out decisive in the generation of the discrete spectra.
Classical and quantum cosmology
Calcagni, Gianluca
2017-01-01
This comprehensive textbook is devoted to classical and quantum cosmology, with particular emphasis on modern approaches to quantum gravity and string theory and on their observational imprint. It covers major challenges in theoretical physics such as the big bang and the cosmological constant problem. An extensive review of standard cosmology, the cosmic microwave background, inflation and dark energy sets the scene for the phenomenological application of all the main quantum-gravity and string-theory models of cosmology. Born of the author's teaching experience and commitment to bridging the gap between cosmologists and theoreticians working beyond the established laws of particle physics and general relativity, this is a unique text where quantum-gravity approaches and string theory are treated on an equal footing. As well as introducing cosmology to undergraduate and graduate students with its pedagogical presentation and the help of 45 solved exercises, this book, which includes an ambitious bibliography...
International Nuclear Information System (INIS)
Sbisà, Fulvio
2015-01-01
The aim of these notes is to provide a self-contained review of why it is generically a problem when a solution of a theory possesses ghost fields among the perturbation modes. We define what a ghost field is and we show that its presence is associated with a classical instability whenever the ghost field interacts with standard fields. We then show that the instability is more severe at quantum level, and that perturbative ghosts can exist only in low energy effective theories. However, if we do not consider very ad hoc choices, compatibility with observational constraints implies that low energy effective ghosts can exist only at the price of giving up Lorentz invariance or locality above the cut-off, in which case the cut-off has to be much lower that the energy scales we currently probe in particle colliders. We also comment on the possible role of extra degrees of freedom which break Lorentz invariance spontaneously. (paper)
Classical mechanics with Mathematica
Romano, Antonio
2018-01-01
This textbook takes a broad yet thorough approach to mechanics, aimed at bridging the gap between classical analytic and modern differential geometric approaches to the subject. Developed by the authors from over 30 years of teaching experience, the presentation is designed to give students an overview of the many different models used through the history of the field—from Newton to Hamilton—while also painting a clear picture of the most modern developments. The text is organized into two parts. The first focuses on developing the mathematical framework of linear algebra and differential geometry necessary for the remainder of the book. Topics covered include tensor algebra, Euclidean and symplectic vector spaces, differential manifolds, and absolute differential calculus. The second part of the book applies these topics to kinematics, rigid body dynamics, Lagrangian and Hamiltonian dynamics, Hamilton–Jacobi theory, completely integrable systems, statistical mechanics of equilibrium, and impulsive dyna...
Mechanical Systems, Classical Models
Teodorescu, Petre P
2009-01-01
This third volume completes the Work Mechanical Systems, Classical Models. The first two volumes dealt with particle dynamics and with discrete and continuous mechanical systems. The present volume studies analytical mechanics. Topics like Lagrangian and Hamiltonian mechanics, the Hamilton-Jacobi method, and a study of systems with separate variables are thoroughly discussed. Also included are variational principles and canonical transformations, integral invariants and exterior differential calculus, and particular attention is given to non-holonomic mechanical systems. The author explains in detail all important aspects of the science of mechanics, regarded as a natural science, and shows how they are useful in understanding important natural phenomena and solving problems of interest in applied and engineering sciences. Professor Teodorescu has spent more than fifty years as a Professor of Mechanics at the University of Bucharest and this book relies on the extensive literature on the subject as well as th...
Quantum models of classical systems
International Nuclear Information System (INIS)
Hájíček, P
2015-01-01
Quantum statistical methods that are commonly used for the derivation of classical thermodynamic properties are extended to classical mechanical properties. The usual assumption that every real motion of a classical mechanical system is represented by a sharp trajectory is not testable and is replaced by a class of fuzzy models, the so-called maximum entropy (ME) packets. The fuzzier are the compared classical and quantum ME packets, the better seems to be the match between their dynamical trajectories. Classical and quantum models of a stiff rod will be constructed to illustrate the resulting unified quantum theory of thermodynamic and mechanical properties. (paper)
International Nuclear Information System (INIS)
Baran, V.
1995-01-01
The thesis has three main parts. In the first part a fourth order quadrupole boson Hamiltonian is semi classically treated through a time-dependent variational principle (TDVP), the variational states being of coherent type for the boson operators b 20 + and 1/√2 (b 22 + + b 2-2 + ). The static ground state is studied as a function of the parameters involved in the model Hamiltonian. Linearizing the classical equations of motion one obtains the RPA approach for the many boson correlations. There are two RPA roots which describe the beta and gamma vibrations, respectively. Several quantization procedures for both small and large amplitude regimes are discussed. The quantized Hamiltonians are compared with some others which were previously obtained by using different methods. A special attention is paid to the quantal states associated to some of the peaks appearing in the Fourier spectrum of the classical action density. Some of the quantal states exhibit a pronounced anharmonic structure. Therefore the procedure may be used for a unified description of small and large amplitude regimes. In the next part the semiclassical foundations of the Coherent State Model are established using the formalism elaborated in the previous section. In the third part the semiclassical treatment through a time-dependent variational principle (TDVP) of the fourth order quadrupole boson Hamiltonian H is continued. In the parameter space of H there are regions, conventionally called as 'nuclear phases', determining specific static properties. Several ground states corresponding to different equilibrium shapes are found as static solutions of classical equations of motion. The non-integrable system may follow a chaotic trajectory. The mechanism of destroying the tori bearing regular orbits and the onset of chaos may depend on nuclear phase. The regular and chaotic motions are analyzed in terms of Poincare sections and Lyapunov largest exponent. Specific features of various phases are
Construction of classical and non-classical coherent photon states
International Nuclear Information System (INIS)
Honegger, Reinhard; Rieckers, Alfred
2001-01-01
It is well known that the diagonal matrix elements of all-order coherent states for the quantized electromagnetic field have to constitute a Poisson distribution with respect to the photon number. The present work gives first the summary of a constructive scheme, developed previously, which determines in terms of an auxiliary Hilbert space all possible off-diagonal elements for the all-order coherent density operators in Fock space and which identifies all extremal coherent states. In terms of this formalism it is then demonstrated that each pure classical coherent state is a uniformly phase locked (quantum) coherent superposition of number states. In a mixed classical coherent state the exponential of the locked phase is shown to be replaced by a rather arbitrary unitary operator in the auxiliary Hilbert space. On the other hand classes for density operators--and for their normally ordered characteristic functions--of non-classical coherent states are obtained, especially by rather weak perturbations of classical coherent states. These illustrate various forms of breaking the classical uniform phase locking and exhibit rather peculiar properties, such as asymmetric fluctuations for the quadrature phase operators. Several criteria for non-classicality are put forward and applied to the elaborated non-classical coherent states, providing counterexamples against too simple arguments for classicality. It is concluded that classicality is only a stable concept for coherent states with macroscopic intensity
RESEARCH ARTICLE Distinct classical and molecular cytogenetics ...
Indian Academy of Sciences (India)
Navya
2017-01-27
,. Universidade Estadual Paulista “Júlio de Mesquita Filho” (UNESP), Av. 24A, 1515, ZIP: 13506-900, Rio Claro, SP, Brazil. 2Instituto de Biociências, Laboratório de Citogenética e Genética Animal, Universidade. Federal de ...
Crowder, Martin J
2001-01-01
If something can fail, it can often fail in one of several ways and sometimes in more than one way at a time. There is always some cause of failure, and almost always, more than one possible cause. In one sense, then, survival analysis is a lost cause. The methods of Competing Risks have often been neglected in the survival analysis literature. Written by a leading statistician, Classical Competing Risks thoroughly examines the probability framework and statistical analysis of data of Competing Risks. The author explores both the theory of the subject and the practicalities of fitting the models to data. In a coherent, self-contained, and sequential account, the treatment moves from the bare bones of the Competing Risks setup and the associated likelihood functions through survival analysis using hazard functions. It examines discrete failure times and the difficulties of identifiability, and concludes with an introduction to the counting-process approach and the associated martingale theory.With a dearth of ...
Grafakos, Loukas
2014-01-01
The main goal of this text is to present the theoretical foundation of the field of Fourier analysis on Euclidean spaces. It covers classical topics such as interpolation, Fourier series, the Fourier transform, maximal functions, singular integrals, and Littlewood–Paley theory. The primary readership is intended to be graduate students in mathematics with the prerequisite including satisfactory completion of courses in real and complex variables. The coverage of topics and exposition style are designed to leave no gaps in understanding and stimulate further study. This third edition includes new Sections 3.5, 4.4, 4.5 as well as a new chapter on “Weighted Inequalities,” which has been moved from GTM 250, 2nd Edition. Appendices I and B.9 are also new to this edition. Countless corrections and improvements have been made to the material from the second edition. Additions and improvements include: more examples and applications, new and more relevant hints for the existing exercises, new exercises, and...
Classical tokamak transport theory
International Nuclear Information System (INIS)
Nocentini, Aldo
1982-01-01
A qualitative treatment of the classical transport theory of a magnetically confined, toroidal, axisymmetric, two-species plasma is presented. The 'weakly collisional' ('banana' and 'plateau') and 'collision dominated' ('Pfirsch-Schlueter' and 'highly collisional') regimes, as well as the Ware effect are discussed. The method used to evaluate the diffusion coffieicnts of particles and heat in the weakly collisional regime is based on stochastic argument, that requires an analysis of the characteristic collision frequencies and lengths for particles moving in a tokamak-like magnetic field. The same method is used to evaluate the Ware effect. In the collision dominated regime on the other hand, the particle and heat fluxes across the magnetic field lines are dominated by macroscopic effects so that, although it is possible to present them as diffusion (in fact, the fluxes turn out to be proportional to the density and temperature gradients), a macroscopic treatment is more appropriate. Hence, fluid equations are used to inveatigate the collision dominated regime, to which particular attention is devoted, having been shown relatively recently that it is more complicated than the usual Pfirsch-Schlueter regime. The whole analysis presented here is qualitative, aiming to point out the relevant physical mechanisms involved in the various regimes more than to develop a rigorous mathematical derivation of the diffusion coefficients, for which appropriate references are given. (author)
Sullivan, Woodruff Turner
1982-01-01
Radio techniques were the nrst to lead astronomy away from the quiescent and limited Universe revealed by traditional observations at optical wave lengths. In the earliest days of radio astronomy, a handful of radio physicists and engineers made one startling discovery after another as they opened up the radio sky. With this collection of classic papers and the extensive intro ductory material, the reader can experience these exciting discoveries, as well as understand the developing techniques and follow the motivations which prompted the various lines of inquiry. For instance he or she will follow in detail the several attempts to detect radio waves from the sun at the turn of the century; the unravelling by Jansky of a "steady hiss type static"; the incredible story of Reber who built a 9 meter dish in his backyard in 1937 and then mapped the Milky Way; the vital discoveries by Hey and colleagues of radio bursts from the Sun and of a discrete source in the constellation of Cygnus; the development of re...
Mathematical optics classical, quantum, and computational methods
Lakshminarayanan, Vasudevan
2012-01-01
Going beyond standard introductory texts, Mathematical Optics: Classical, Quantum, and Computational Methods brings together many new mathematical techniques from optical science and engineering research. Profusely illustrated, the book makes the material accessible to students and newcomers to the field. Divided into six parts, the text presents state-of-the-art mathematical methods and applications in classical optics, quantum optics, and image processing. Part I describes the use of phase space concepts to characterize optical beams and the application of dynamic programming in optical wave
... Sarcoma Treatment Childhood Vascular Tumors Treatment Research Kaposi Sarcoma Treatment (PDQ®)–Patient Version General Information About Kaposi Sarcoma Go to Health Professional Version Key Points Kaposi ...
Quantum symmetries of classical spaces
Bhowmick, Jyotishman; Goswami, Debashish; Roy, Subrata Shyam
2009-01-01
We give a general scheme for constructing faithful actions of genuine (noncommutative as $C^*$ algebra) compact quantum groups on classical topological spaces. Using this, we show that: (i) a compact connected classical space can have a faithful action by a genuine compact quantum group, and (ii) there exists a spectral triple on a classical connected compact space for which the quantum group of orientation and volume preserving isometries (in the sense of \\cite{qorient}) is a genuine quantum...
Dynamics of unitarization by classicalization
International Nuclear Information System (INIS)
Dvali, Gia; Pirtskhalava, David
2011-01-01
We study dynamics of the classicalization phenomenon suggested in G. Dvali et al. , according to which a class of non-renormalizable theories self-unitarizes at very high-energies via creation of classical configurations (classicalons). We study this phenomenon in an explicit model of derivatively-self-coupled scalar that serves as a prototype for a Nambu-Goldstone-Stueckelberg field. We prepare the initial state in form of a collapsing wave-packet of a small occupation number but of very high energy, and observe that the classical configuration indeed develops. Our results confirm the previous estimates, showing that because of self-sourcing the wave-packet forms a classicalon configuration with radius that increases with center of mass energy. Thus, classicalization takes place before the waves get any chance of probing short-distances. The self-sourcing by energy is the crucial point, which makes classicalization phenomenon different from the ordinary dispersion of the wave-packets in other interacting theories. Thanks to this, unlike solitons or other non-perturbative objects, the production of classicalons is not only unsuppressed, but in fact dominates the high-energy scattering. In order to make the difference between classicalizing and non-classicalizing theories clear, we use a language in which the scattering cross section in a generic theory can be universally understood as a geometric cross section set by a classical radius down to which waves can propagate freely, before being scattered. We then show, that in non-classicalizing examples this radius shrinks with increasing energy and becomes microscopic, whereas in classicalizing theories expands and becomes macroscopic. We study analogous scattering in a Galileon system and discover that classicalization also takes place there, although somewhat differently. We thus observe, that classicalization is source-sensitive and that Goldstones pass the first test.
Saudi experience with classic homocystinuria
International Nuclear Information System (INIS)
Al-Essa, M.; Ozand, P.T.; Rashed, M.
1998-01-01
Classic homocystinuria is an autosomal recessive disorder due to cystathionine beta-synthase deficiency. The clinical, radiological and neurophysiological findings of classic homcystinuria diagnosed at King Faisal Specialist Hospital and Research Centre (KFSH and RC) are presented in this report. Twenty-four patients (15 females and 9 males) were referred to KFSH and RC for work-up of mental retardation, seizures, thrombo-embolic episodes and dislocation of the ocular lenses. The common clinical findings included ectopia lentis (20 patients), skeletal system involvement (18 patients), vascular system involvement (9patients), and mental retardation (all patients to varying degrees). Unusual findings consisted of a patient who developed severe lower gastrointestinal bleeding, a patient with insulin-dependent diabetes mellitus, probably due to vasculopathy, and other having severe bronchiectasis, which may have been due to fibrillin disruption, and required the resection of a lobe of lung. The parents of 21 patients were first-degree relatives, and 19 patients had one or more family members affected by the same disease. All patients had markedly elevated plasma levels of methionine. Cystathionine synthase activity in the fibroblast was measured in 25% of the patients and was deficient. Only four patients responded to pyridoxine and their methionine level decreased to almost normal range. The aim of this study was to increase the awareness of this disease in the scientific and medical community, in particular in the general pediatrician working in Saudi Arabia who first encounters the clinical manifestations of disease. Early detection through tandem mass spectrometry of blood spot screening and treatment are important and may prevent the major complications of this disease. (author)
Globalising the classical foundations of IPE thought
Directory of Open Access Journals (Sweden)
Eric Helleiner
2015-12-01
Full Text Available Abstract Current efforts to teach and research the historical foundations of IPE thought in classical political economy in the 18th, 19th and early 20th centuries centre largely on European and American thinkers. If a more extensive 'global conversation' is to be fostered in the field today, the perspectives of thinkers in other regions need to be recognised, and brought into the mainstream of its intellectual history. As a first step towards 'globalising' the classical foundations of IPE thought, this article demonstrates some ways in which thinkers located beyond Europe and the United States engaged with and contributed to debates associated with the three well-known classical traditions on which current IPE scholarship often draws: economic liberalism, economic nationalism and Marxism. It also reveals the extensive nature of 'global conversations' about IPE issues in this earlier era.
The classic: Bone morphogenetic protein.
Urist, Marshall R; Strates, Basil S
2009-12-01
This Classic Article is a reprint of the original work by Marshall R. Urist and Basil S. Strates, Bone Morphogenetic Protein. An accompanying biographical sketch of Marshall R. Urist, MD is available at DOI 10.1007/s11999-009-1067-4; a second Classic Article is available at DOI 10.1007/s11999-009-1069-2; and a third Classic Article is available at DOI 10.1007/s11999-009-1070-9. The Classic Article is copyright 1971 by Sage Publications Inc. Journals and is reprinted with permission from Urist MR, Strates BS. Bone morphogenetic protein. J Dent Res. 1971;50:1392-1406.
Innovation: the classic traps.
Kanter, Rosabeth Moss
2006-11-01
Never a fad, but always in or out of fashion, innovation gets rediscovered as a growth enabler every half dozen years. Too often, though, grand declarations about innovation are followed by mediocre execution that produces anemic results, and innovation groups are quietly disbanded in cost-cutting drives. Each managerial generation embarks on the same enthusiastic quest for the next new thing. And each generation faces the same vexing challenges- most of which stem from the tensions between protecting existing revenue streams critical to current success and supporting new concepts that may be crucial to future success. In this article, Harvard Business School professor Rosabeth Moss Kanter reflects on the four major waves of innovation enthusiasm she's observed over the past 25 years. She describes the classic mistakes companies make in innovation strategy, process, structure, and skills assessment, illustrating her points with a plethora of real-world examples--including AT&T Worldnet, Timberland, and Ocean Spray. A typical strategic blunder is when managers set their hurdles too high or limit the scope of their innovation efforts. Quaker Oats, for instance, was so busy in the 1990s making minor tweaks to its product formulas that it missed larger opportunities in distribution. A common process mistake is when managers strangle innovation efforts with the same rigid planning, budgeting, and reviewing approaches they use in their existing businesses--thereby discouraging people from adapting as circumstances warrant. Companies must be careful how they structure fledgling entities alongside existing ones, Kanter says, to avoid a clash of cultures and agendas--which Arrow Electronics experienced in its attempts to create an online venture. Finally, companies commonly undervalue and underinvest in the human side of innovation--for instance, promoting individuals out of innovation teams long before their efforts can pay off. Kanter offers practical advice for avoiding
2007-01-01
M51, whose name comes from being the 51st entry in Charles Messier's catalog, is considered to be one of the classic examples of a spiral galaxy. At a distance of about 30 million light-years from Earth, it is also one of the brightest spirals in the night sky. A composite image of M51, also known as the Whirlpool Galaxy, shows the majesty of its structure in a dramatic new way through several of NASA's orbiting observatories. X-ray data from NASA's Chandra X-ray Observatory reveals point-like sources (purple) that are black holes and neutron stars in binary star systems. Chandra also detects a diffuse glow of hot gas that permeates the space between the stars. Optical data from the Hubble Space Telescope (green) and infrared emission from the Spitzer Space Telescope (red) both highlight long lanes in the spiral arms that consist of stars and gas laced with dust. A view of M51 with the Galaxy Evolution Explorer telescope shows hot, young stars that produce lots of ultraviolet energy (blue). The textbook spiral structure is thought be the result of an interaction M51 is experiencing with its close galactic neighbor, NGC 5195, which is seen just above. Some simulations suggest M51's sharp spiral shape was partially caused when NGC 5195 passed through its main disk about 500 million years ago. This gravitational tug of war may also have triggered an increased level of star formation in M51. The companion galaxy's pull would be inducing extra starbirth by compressing gas, jump-starting the process by which stars form.
Quantum flesh on classical bones: Semiclassical bridges across the quantum-classical divide
Energy Technology Data Exchange (ETDEWEB)
Bokulich, Alisa [Center for Philosophy and History of Science, Boston University, Boston, MA (United States)
2014-07-01
Traditionally quantum mechanics is viewed as having made a sharp break from classical mechanics, and the concepts and methods of these two theories are viewed as incommensurable with one another. A closer examination of the history of quantum mechanics, however, reveals that there is a strong sense in which quantum mechanics was built on the backbone of classical mechanics. As a result, there is a considerable structural continuity between these two theories, despite their important differences. These structural continuities provide a ground for semiclassical methods in which classical structures, such as trajectories, are used to investigate and model quantum phenomena. After briefly tracing the history of semiclassical approaches, I show how current research in semiclassical mechanics is revealing new bridges across the quantum-classical divide.
Classic romance in electronic arrangement
Directory of Open Access Journals (Sweden)
Kizin M.M.
2017-03-01
Full Text Available this article analyses the transformation of the performing arts of classical romance in the terms of electronic sound and performance via electronic sounds arrangements. The author focuses on the problem of synthesis of electronic sound arrangements and classical romance, offering to acquire the skills of the creative process in constantly changing conditions of live performances.
COMPETITION: CLASSICAL VERSUS NEOCLASSICAL VIEW
Mihaela Cornelia Sandu
2013-01-01
Competition is an important element from economical theory. Over time it has experienced several definitions and classifications much of them being contradictory. In this paper I will make a parallel between classical and neoclassical point of view according to competition. Keywords. Competition; neoclassical theory; classical theory; monopolistic; perfect competition.
Classical models for Regge trajectories
International Nuclear Information System (INIS)
Biedenharn, L.C.; Van Dam, H.; Marmo, G.; Morandi, G.; Mukunda, N.; Samuel, J.; Sudarshan, E.C.G.
1987-01-01
Two classical models for particles with internal structure and which describe Regge trajectories are developed. The remarkable geometric and other properties of the two internal spaces are highlighted. It is shown that the conditions of positive time-like four-velocity and energy momentum for the classical system imply strong and physically reasonable conditions on the Regge mass-spin relationship
Sum rules in classical scattering
International Nuclear Information System (INIS)
Bolle, D.; Osborn, T.A.
1981-01-01
This paper derives sum rules associated with the classical scattering of two particles. These sum rules are the analogs of Levinson's theorem in quantum mechanics which provides a relationship between the number of bound-state wavefunctions and the energy integral of the time delay of the scattering process. The associated classical relation is an identity involving classical time delay and an integral over the classical bound-state density. We show that equalities between the Nth-order energy moment of the classical time delay and the Nth-order energy moment of the classical bound-state density hold in both a local and a global form. Local sum rules involve the time delay defined on a finite but otherwise arbitrary coordinate space volume S and the bound-state density associated with this same region. Global sum rules are those that obtain when S is the whole coordinate space. Both the local and global sum rules are derived for potentials of arbitrary shape and for scattering in any space dimension. Finally the set of classical sum rules, together with the known quantum mechanical analogs, are shown to provide a unified method of obtaining the high-temperature expansion of the classical, respectively the quantum-mechanical, virial coefficients
'Leonard pairs' in classical mechanics
International Nuclear Information System (INIS)
Zhedanov, Alexei; Korovnichenko, Alyona
2002-01-01
Leonard pairs (LP) are matrices with the property of mutual tri-diagonality. We introduce and study a classical analogue of LP. We show that corresponding classical 'Leonard' dynamical variables satisfy non-linear relations of the AW-type with respect to Poisson brackets. (author)
Quantum mechanics from classical statistics
International Nuclear Information System (INIS)
Wetterich, C.
2010-01-01
Quantum mechanics can emerge from classical statistics. A typical quantum system describes an isolated subsystem of a classical statistical ensemble with infinitely many classical states. The state of this subsystem can be characterized by only a few probabilistic observables. Their expectation values define a density matrix if they obey a 'purity constraint'. Then all the usual laws of quantum mechanics follow, including Heisenberg's uncertainty relation, entanglement and a violation of Bell's inequalities. No concepts beyond classical statistics are needed for quantum physics - the differences are only apparent and result from the particularities of those classical statistical systems which admit a quantum mechanical description. Born's rule for quantum mechanical probabilities follows from the probability concept for a classical statistical ensemble. In particular, we show how the non-commuting properties of quantum operators are associated to the use of conditional probabilities within the classical system, and how a unitary time evolution reflects the isolation of the subsystem. As an illustration, we discuss a classical statistical implementation of a quantum computer.
International Nuclear Information System (INIS)
Race, C P; Mason, D R; Foo, M H F; Foulkes, W M C; Sutton, A P; Horsfield, A P
2013-01-01
By simulating the passage of heavy ions along open channels in a model crystalline metal using semi-classical Ehrenfest dynamics we directly investigate the nature of non-adiabatic electronic effects. Our time-dependent tight-binding approach incorporates both an explicit quantum mechanical electronic system and an explicit representation of a set of classical ions. The coupled evolution of the ions and electrons allows us to explore phenomena that lie beyond the approximations made in classical molecular dynamics simulations and in theories of electronic stopping. We report a velocity-dependent charge-localization phenomenon not predicted by previous theoretical treatments of channelling. This charge localization can be attributed to the excitation of electrons into defect states highly localized on the channelling ion. These modes of excitation only become active when the frequency at which the channelling ion moves from interstitial point to equivalent interstitial point matches the frequency corresponding to excitations from the Fermi level into the localized states. Examining the stopping force exerted on the channelling ion by the electronic system, we find broad agreement with theories of slow ion stopping (a stopping force proportional to velocity) for a low velocity channelling ion (up to about 0.5 nm fs −1 from our calculations), and a reduction in stopping power attributable to the charge localization effect at higher velocities. By exploiting the simplicity of our electronic structure model we are able to illuminate the physics behind the excitation processes that we observe and present an intuitive picture of electronic stopping from a real-space, chemical perspective. (paper)
Classicalization of Gravitons and Goldstones
Dvali, Gia; Kehagias, Alex
2011-01-01
We establish a close parallel between classicalization of gravitons and derivatively-coupled Nambu-Goldstone-type scalars. We show, that black hole formation in high energy scattering process represents classicalization with the classicalization radius given by Schwarzschild radius of center of mass energy, and with the precursor of black hole entropy being given by number of soft quanta composing this classical configuration. Such an entropy-equivalent is defined for scalar classicalons also and is responsible for exponential suppression of their decay into small number of final particles. This parallel works in both ways. For optimists that are willing to hypothesize that gravity may indeed self-unitarize at high energies via black hole formation, it illustrates that the Goldstones may not be much different in this respect, and they classicalize essentially by similar dynamics as gravitons. In the other direction, it may serve as an useful de-mystifier of via-black-hole-unitarization process and of the role...
National Research Council Canada - National Science Library
Ritch, Robert; Caronia, Ronald M
1999-01-01
... Elimination of Intraocular Fluid J.S. Friedenwald The Formation of the Intraocular Fluid. Proctor Award Lecture of the Association for Research in Ophthalmology W.M. Grant, Tonographic Method for Measuring the Facility and Rate of Aqueous Flow in Human Eyes P.A. Chandler , Malignant Glaucoma B. Becker, Decrease in Intraocular Pressure in Man by a Carbo...
Supplemental Reading for Ninth Graders: Classic or Young Adult Literature
Hill, Katherine Jane Roney
2012-01-01
The project addressed the debate over supplemental literature: young adult or classic selections to better support teaching ninth graders Tennessee's English I curriculum standards. Research supported both classical and contemporary literature for teaching ninth graders, making it difficult to determine which type of literature might produce the…
Kutzner, Florian; Vogel, Tobias; Freytag, Peter; Fiedler, Klaus
2011-01-01
In the present research, we argue for the robustness of illusory correlations (ICs, Hamilton & Gifford, 1976) regarding two boundary conditions suggested in previous research. First, we argue that ICs are maintained under extended experience. Using simulations, we derive conflicting predictions. Whereas noise-based accounts predict ICs to be maintained (Fielder, 2000; Smith, 1991), a prominent account based on discrepancy-reducing feedback learning predicts ICs to disappear (Van Rooy et al., 2003). An experiment involving 320 observations with majority and minority members supports the claim that ICs are maintained. Second, we show that actively using the stereotype to make predictions that are met with reward and punishment does not eliminate the bias. In addition, participants' operant reactions afford a novel online measure of ICs. In sum, our findings highlight the robustness of ICs that can be explained as a result of unbiased but noisy learning.
Loire Classics: Reviving Classicism in some Loire Poets
Directory of Open Access Journals (Sweden)
Wim Verbaal
2017-06-01
Full Text Available The term 'Loire poets' has come to refer to a rather undefinable group of poets that in the second half of the eleventh century distinguishes itself through its refined poetics. They are often characterized as medieval humanists thanks to their renewed interest in the classics. Sometimes their movement is labelled a 'classicist' one. But what does this 'classicism' mean? Is it even permitted to speak of medieval 'classicisms'? This contribution approaches the question of whether we can apply this modern label to pre-modern phenomena. Moreover, it explores the changes in attitude towards the classics that sets the Loire poets off from their predecessors and contemporaries. The article focuses on poems by Hildebert of Lavardin, Baudri of Bourgueil, Marbod of Rennes, and Geoffrey of Reims. They are compared with some contemporary poets, such as Reginald of Canterbury and Sigebert of Gembloux.
Developing of Thai Classical Music Ensemble in Rattanakosin Period
Pansak Vandee
2013-01-01
The research titled “Developing of Thai Classical Music Ensemble in Rattanakosin Period" aimed 1) to study the history of Thai Classical Music Ensemble in Rattanakosin Period and 2) to analyze changing in each period of Rattanakosin Era. This is the historical and documentary research. The data was collected by in-depth interview those musicians, and academic music experts and field study. The focus group discussion was conducted to analyze and conclude the findings. The research found that t...
THE BUREAUCRATIC PHENOMENON: CLASSICAL CONCEPTS
Directory of Open Access Journals (Sweden)
Дама Ибрагима
2013-09-01
Full Text Available Aim of this article - to analyze Hegel and Karl Marx’s classic bureaucracy theories and also Max Weber’s concept of rational bureaucracy and its development in the works of Herbert Simon, Robert Merton, Peter Blau and Michel Crozier. It shows that the above listed researchers only undertook a change of terminology within the same theoretical tradition. The article describes different approaches to the bureaucratic system of administrative schools of the late 1950s and early 1980s. Major conclusions in the article include the following: administering the state apparatus consists in the organization of government on the basis of regulated rights, mandatory procedures that are invoked to ensure balance in the interest of man and society; bad effectiveness of government, infringement of the rights and freedoms of the individual is the result of dysfunction in the state apparatus; the struggle against it can be carried out with the help of administrative, economical and legal methods.DOI: http://dx.doi.org/10.12731/2218-7405-2013-6-45
Quantum Computing's Classical Problem, Classical Computing's Quantum Problem
Van Meter, Rodney
2013-01-01
Tasked with the challenge to build better and better computers, quantum computing and classical computing face the same conundrum: the success of classical computing systems. Small quantum computing systems have been demonstrated, and intermediate-scale systems are on the horizon, capable of calculating numeric results or simulating physical systems far beyond what humans can do by hand. However, to be commercially viable, they must surpass what our wildly successful, highly advanced classica...
The Wigner representation of classical mechanics, quantization and classical limit
International Nuclear Information System (INIS)
Bolivar, A.O.
2001-08-01
Starting from the Liouvillian formulation of classical physics it is possible by means of a Fourier transform to introduce the Wigner representation and to derive an operator structure to classical mechanisms. The importance of this new representation lies on the fact that it turns out to be suitable route to establish a general method of quantization directly from the equations of motion without alluding to the existence of Hamiltonian and Lagrangian functions. Following this approach we quantize only the motion of a Browian particle with non-linear friction in the Markovian approximation - the thermal bath may be quantum or classical -, thus when the bath is classically described we obtain a master equation which reduces to Caldeira-Legget equation for the linear friction case, and when the reservoir is quantum we get an equation reducing to the one found by Caldeira et al. By neglecting the environmental influence we show that the system can be approximately described by equations of motion in terms of wave function, such as the Schrodinger-Langevin equation and equations of the Caldirola-Kanai type. Finally to make the present study self-consistent we evaluate the classical limit of these dynamical equations employing a new classical limiting method h/2π → 0. (author)
The Wigner representation of classical mechanics, quantization and classical limit
Energy Technology Data Exchange (ETDEWEB)
Bolivar, A.O. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)
2001-08-01
Starting from the Liouvillian formulation of classical physics it is possible by means of a Fourier transform to introduce the Wigner representation and to derive an operator structure to classical mechanisms. The importance of this new representation lies on the fact that it turns out to be suitable route to establish a general method of quantization directly from the equations of motion without alluding to the existence of Hamiltonian and Lagrangian functions. Following this approach we quantize only the motion of a Browian particle with non-linear friction in the Markovian approximation - the thermal bath may be quantum or classical -, thus when the bath is classically described we obtain a master equation which reduces to Caldeira-Legget equation for the linear friction case, and when the reservoir is quantum we get an equation reducing to the one found by Caldeira et al. By neglecting the environmental influence we show that the system can be approximately described by equations of motion in terms of wave function, such as the Schrodinger-Langevin equation and equations of the Caldirola-Kanai type. Finally to make the present study self-consistent we evaluate the classical limit of these dynamical equations employing a new classical limiting method h/2{pi} {yields} 0. (author)
Mathematical methods of classical physics
Cortés, Vicente
2017-01-01
This short primer, geared towards students with a strong interest in mathematically rigorous approaches, introduces the essentials of classical physics, briefly points out its place in the history of physics and its relation to modern physics, and explains what benefits can be gained from a mathematical perspective. As a starting point, Newtonian mechanics is introduced and its limitations are discussed. This leads to and motivates the study of different formulations of classical mechanics, such as Lagrangian and Hamiltonian mechanics, which are the subjects of later chapters. In the second part, a chapter on classical field theories introduces more advanced material. Numerous exercises are collected in the appendix.
Classicality of quantum information processing
International Nuclear Information System (INIS)
Poulin, David
2002-01-01
The ultimate goal of the classicality program is to quantify the amount of quantumness of certain processes. Here, classicality is studied for a restricted type of process: quantum information processing (QIP). Under special conditions, one can force some qubits of a quantum computer into a classical state without affecting the outcome of the computation. The minimal set of conditions is described and its structure is studied. Some implications of this formalism are the increase of noise robustness, a proof of the quantumness of mixed state quantum computing, and a step forward in understanding the very foundation of QIP
Directory of Open Access Journals (Sweden)
Katherine Steiner
2016-10-01
Full Text Available Classics as a discipline has always taken advantage of digital methods in research, with projects dating back to the 1970s and earlier. This article examines the integration of classics and computing, and presents a case study of EpiDoc, a markup language used in epigraphy. Positive evidence can be found for EpiDoc’s influence on collaboration, with several current collaborative projects, and the nature of the technology encouraging open, reusable scholarship. The Inscriptions of Aphrodisias project illustrates much of the potential of electronic publishing. EpiDoc’s effect on research questions themselves remains inconclusive, although definite possibilities for the future are apparent. Opening up these conclusions to the wider digital classics community shows a trend towards collaboration in recent publications and projects, as well as a gradual uptake of electronic publication.
Quantum machine learning: a classical perspective
Ciliberto, Carlo; Herbster, Mark; Ialongo, Alessandro Davide; Pontil, Massimiliano; Severini, Simone; Wossnig, Leonard
2018-01-01
Recently, increased computational power and data availability, as well as algorithmic advances, have led machine learning (ML) techniques to impressive results in regression, classification, data generation and reinforcement learning tasks. Despite these successes, the proximity to the physical limits of chip fabrication alongside the increasing size of datasets is motivating a growing number of researchers to explore the possibility of harnessing the power of quantum computation to speed up classical ML algorithms. Here we review the literature in quantum ML and discuss perspectives for a mixed readership of classical ML and quantum computation experts. Particular emphasis will be placed on clarifying the limitations of quantum algorithms, how they compare with their best classical counterparts and why quantum resources are expected to provide advantages for learning problems. Learning in the presence of noise and certain computationally hard problems in ML are identified as promising directions for the field. Practical questions, such as how to upload classical data into quantum form, will also be addressed. PMID:29434508
Natarajan, P N
2017-01-01
This book presents results about certain summability methods, such as the Abel method, the Norlund method, the Weighted mean method, the Euler method and the Natarajan method, which have not appeared in many standard books. It proves a few results on the Cauchy multiplication of certain summable series and some product theorems. It also proves a number of Steinhaus type theorems. In addition, it introduces a new definition of convergence of a double sequence and double series and proves the Silverman-Toeplitz theorem for four-dimensional infinite matrices, as well as Schur's and Steinhaus theorems for four-dimensional infinite matrices. The Norlund method, the Weighted mean method and the Natarajan method for double sequences are also discussed in the context of the new definition. Divided into six chapters, the book supplements the material already discussed in G.H.Hardy's Divergent Series. It appeals to young researchers and experienced mathematicians who wish to explore new areas in Summability Theory.
Classical Limit and Quantum Logic
Losada, Marcelo; Fortin, Sebastian; Holik, Federico
2018-02-01
The analysis of the classical limit of quantum mechanics usually focuses on the state of the system. The general idea is to explain the disappearance of the interference terms of quantum states appealing to the decoherence process induced by the environment. However, in these approaches it is not explained how the structure of quantum properties becomes classical. In this paper, we consider the classical limit from a different perspective. We consider the set of properties of a quantum system and we study the quantum-to-classical transition of its logical structure. The aim is to open the door to a new study based on dynamical logics, that is, logics that change over time. In particular, we appeal to the notion of hybrid logics to describe semiclassical systems. Moreover, we consider systems with many characteristic decoherence times, whose sublattices of properties become distributive at different times.
New perspectives on classical electromagnetism
Cote, Paul J.
2009-01-01
The fallacies associated with the gauge concept in electromagnetism are illustrated. A clearer and more valid formulation of the basics of classical electromagnetism is provided by recognizing existing physical constraints as well as the physical reality of the vector potential.
Classical Mechanics and Symplectic Integration
DEFF Research Database (Denmark)
Nordkvist, Nikolaj; Hjorth, Poul G.
2005-01-01
Content: Classical mechanics: Calculus of variations, Lagrange’s equations, Symmetries and Noether’s theorem, Hamilton’s equations, cannonical transformations, integrable systems, pertubation theory. Symplectic integration: Numerical integrators, symplectic integrators, main theorem on symplectic...
Classical conditioning in the treatment of psoriasis.
Ader, R
2000-11-01
It has been argued that the placebo effect represents a learned response. Research is suggested to address the utility of applying principles derived from classical (Pavlovian) conditioning to the design of drug treatment protocols. In the present instance, it is hypothesized that, by capitalizing on conditioned pharmacotherapeutic responses, it may be possible to reduce the cumulative amount of corticosteroid medication used in the treatment of psoriasis.
Classical theory of radiating strings
Copeland, Edmund J.; Haws, D.; Hindmarsh, M.
1990-01-01
The divergent part of the self force of a radiating string coupled to gravity, an antisymmetric tensor and a dilaton in four dimensions are calculated to first order in classical perturbation theory. While this divergence can be absorbed into a renormalization of the string tension, demanding that both it and the divergence in the energy momentum tensor vanish forces the string to have the couplings of compactified N = 1 D = 10 supergravity. In effect, supersymmetry cures the classical infinities.
Teaching Classical Mechanics using Smartphones
Chevrier, Joel; Madani, Laya; Ledenmat, Simon; Bsiesy, Ahmad
2012-01-01
Using a personal computer and a smartphone, iMecaProf is a software that provides a complete teaching environment for practicals associated to a Classical Mechanics course. iMecaProf proposes a visual, real time and interactive representation of data transmitted by a smartphone using the formalism of Classical Mechanics. Using smartphones is more than using a set of sensors. iMecaProf shows students that important concepts of physics they here learn, are necessary to control daily life smartp...
Dynamical systems in classical mechanics
Kozlov, V V
1995-01-01
This book shows that the phenomenon of integrability is related not only to Hamiltonian systems, but also to a wider variety of systems having invariant measures that often arise in nonholonomic mechanics. Each paper presents unique ideas and original approaches to various mathematical problems related to integrability, stability, and chaos in classical dynamics. Topics include… the inverse Lyapunov theorem on stability of equilibria geometrical aspects of Hamiltonian mechanics from a hydrodynamic perspective current unsolved problems in the dynamical systems approach to classical mechanics
Quantum money with classical verification
Energy Technology Data Exchange (ETDEWEB)
Gavinsky, Dmitry [NEC Laboratories America, Princeton, NJ (United States)
2014-12-04
We propose and construct a quantum money scheme that allows verification through classical communication with a bank. This is the first demonstration that a secure quantum money scheme exists that does not require quantum communication for coin verification. Our scheme is secure against adaptive adversaries - this property is not directly related to the possibility of classical verification, nevertheless none of the earlier quantum money constructions is known to possess it.
Quantum money with classical verification
International Nuclear Information System (INIS)
Gavinsky, Dmitry
2014-01-01
We propose and construct a quantum money scheme that allows verification through classical communication with a bank. This is the first demonstration that a secure quantum money scheme exists that does not require quantum communication for coin verification. Our scheme is secure against adaptive adversaries - this property is not directly related to the possibility of classical verification, nevertheless none of the earlier quantum money constructions is known to possess it
Quantum formalism for classical statistics
Wetterich, C.
2018-06-01
In static classical statistical systems the problem of information transport from a boundary to the bulk finds a simple description in terms of wave functions or density matrices. While the transfer matrix formalism is a type of Heisenberg picture for this problem, we develop here the associated Schrödinger picture that keeps track of the local probabilistic information. The transport of the probabilistic information between neighboring hypersurfaces obeys a linear evolution equation, and therefore the superposition principle for the possible solutions. Operators are associated to local observables, with rules for the computation of expectation values similar to quantum mechanics. We discuss how non-commutativity naturally arises in this setting. Also other features characteristic of quantum mechanics, such as complex structure, change of basis or symmetry transformations, can be found in classical statistics once formulated in terms of wave functions or density matrices. We construct for every quantum system an equivalent classical statistical system, such that time in quantum mechanics corresponds to the location of hypersurfaces in the classical probabilistic ensemble. For suitable choices of local observables in the classical statistical system one can, in principle, compute all expectation values and correlations of observables in the quantum system from the local probabilistic information of the associated classical statistical system. Realizing a static memory material as a quantum simulator for a given quantum system is not a matter of principle, but rather of practical simplicity.
International Nuclear Information System (INIS)
Lamb, W.E. Jr.
1981-12-01
This final report describes research on the theory of isotope separation produced by the illumination of polyatomic molecules by intense infrared laser radiation. This process is investigated by treating the molecule, sulfur hexafluoride, as a system of seven classical particles that obey the Newtonian equations of motion. A minicomputer is used to integrate these differential equations. The particles are acted on by interatomic forces, and by the time-dependent electric field of the laser. We have a very satisfactory expression for the interaction of the laser and the molecule which is compatible with infrared absorption and spectroscopic data. The interatomic potential is capable of improvement, and progress on this problem is still being made. We have made several computer runs of the dynamical behavior of the molecule using a reasonably good model for the interatomic force law. For the laser parameters chosen, we find that typically the molecule passes quickly through the resonance region into the quasi-continuum and even well into the real continuum before dissociation actually occurs. When viewed on a display terminal, the motions are exceedingly complex. As an aid to the visualization of the process, we have made a number of 16 mm movies depicting a three-dimensional representation of the motion of the seven particles. These show even more clearly the enormous complexity of the motions, and make clear the desirability of finding ways of characterizing the motion in simple ways without giving all of the numerical detail. One of the ways to do this is to introduce statistical parameters such as a temperature associated with the distribution of kinetic energies of the single particle. We have made such an analysis of our data runs, and have found favorable indications that such methods will prove useful in keeping track of the dynamical histories
Lamb, W. E. Jr.
1981-12-01
This final report describes research on the theory of isotope separation produced by the illumination of polyatomic molecules by intense infrared laser radiation. This process is investigated by treating the molecule, sulfur hexafluoride, as a system of seven classical particles that obey the Newtonian equations of motion. A minicomputer is used to integrate these differential equations. The particles are acted on by interatomic forces, and by the time-dependent electric field of the laser. We have a very satisfactory expression for the interaction of the laser and the molecule which is compatible with infrared absorption and spectroscopic data. The interatomic potential is capable of improvement, and progress on this problem is still being made. We have made several computer runs of the dynamical behavior of the molecule using a reasonably good model for the interatomic force law. For the laser parameters chosen, we find that typically the molecule passes quickly through the resonance region into the quasi-continuum and even well into the real continuum before dissociation actually occurs. When viewed on a display terminal, the motions are exceedingly complex. As an aid to the visualization of the process, we have made a number of 16 mm movies depicting a three-dimensional representation of the motion of the seven particles. These show even more clearly the enormous complexity of the motions, and make clear the desirability of finding ways of characterizing the motion in simple ways without giving all of the numerical detail. One of the ways to do this is to introduce statistical parameters such as a temperature associated with the distribution of kinetic energies of the single particle. We have made such an analysis of our data runs, and have found favorable indications that such methods will prove useful in keeping track of the dynamical histories.
Creech, Andrea; Papageorgi, Ioulia; Duffy, Celia; Morton, Frances; Hadden, Elizabeth; Potter, John; De Bezenac, Christophe; Whyton, Tony; Himonides, Evangelos; Welch, Graham
2008-01-01
The research project "Investigating Musical Performance: Comparative Studies in Advanced Musical Learning" was devised to investigate how classical, popular, jazz and Scottish traditional musicians deepen and develop their learning about performance in undergraduate, postgraduate and wider music community contexts. The aim of this paper is to…
Beyond quantum-classical analogies: high time for agreement?
Marrocco, Michele
Lately, many quantum-classical analogies have been investigated and published in many acknowledged journals. Such a surge of research on conceptual connections between quantum and classical physics forces us to ask whether the correspondence between the quantum and classical interpretation of the reality is deeper than the correspondence principle stated by Bohr. Here, after a short introduction to quantum-classical analogies from the recent literature, we try to examine the question from the perspective of a possible agreement between quantum and classical laws. A paradigmatic example is given in the striking equivalence between the classical Mie theory of electromagnetic scattering from spherical scatterers and the corresponding quantum-mechanical wave scattering analyzed in terms of partial waves. The key features that make the correspondence possible are examined and finally employed to deal with the fundamental blackbody problem that marks the initial separation between classical and quantum physics. The procedure allows us to recover the blackbody spectrum in classical terms and the proof is rich in consequences. Among them, the strong analogy between the quantum vacuum and its classical counterpart.
Emerging Connections: Quantum & Classical Optics Incubator Program Book
Energy Technology Data Exchange (ETDEWEB)
Lesky, Marcia [Optical Society of America, Washington, DC (United States)
2016-11-06
The Emerging Connections: Quantum & Classical Optics Incubator was a scientific meeting held in Washington, DC on 6-8 November 2016. This Incubator provided unique and focused experiences and valuable opportunities to discuss advances, challenges and opportunities regarding this important area of research. Quantum optics and classical optics have coexisted for nearly a century as two distinct, but consistent descriptions of light in their respective domains. Recently, a number of detailed examinations of the structure of classical light beams have revealed that effects widely thought to be solely quantum in origin also have a place in classical optics. These new quantum-classical connections are informing classical optics in meaningful ways specifically by expanding understanding of optical coherence. Simultaneously, relationships discovered with classical light beams now also serve as a vehicle to illuminate concepts that no longer solely belong to the quantum realm. Interference, polarization, coherence, complementarity and entanglement are a partial list of elementary notions that now appear to belong to both quantum and classical optics. The goal of this meeting was to bring emerging quantum-classical links into wider view and to indicate directions in which forthcoming and future work would promote discussion and lead to a more unified understanding of optics.
Classical Photogrammetry and Uav - Selected Ascpects
Mikrut, S.
2016-06-01
The UAV technology seems to be highly future-oriented due to its low costs as compared to traditional aerial images taken from classical photogrammetry aircrafts. The AGH University of Science and Technology in Cracow - Department of Geoinformation, Photogrammetry and Environmental Remote Sensing focuses mainly on geometry and radiometry of recorded images. Various scientific research centres all over the world have been conducting the relevant research for years. The paper presents selected aspects of processing digital images made with the UAV technology. It provides on a practical example a comparison between a digital image taken from an airborne (classical) height, and the one made from an UAV level. In his research the author of the paper is trying to find an answer to the question: to what extent does the UAV technology diverge today from classical photogrammetry, and what are the advantages and disadvantages of both methods? The flight plan was made over the Tokarnia Village Museum (more than 0.5 km2) for two separate flights: the first was made by an UAV - System FT-03A built by FlyTech Solution Ltd. The second was made with the use of a classical photogrammetric Cesna aircraft furnished with an airborne photogrammetric camera (Ultra Cam Eagle). Both sets of photographs were taken with pixel size of about 3 cm, in order to have reliable data allowing for both systems to be compared. The project has made aerotriangulation independently for the two flights. The DTM was generated automatically, and the last step was the generation of an orthophoto. The geometry of images was checked under the process of aerotriangulation. To compare the accuracy of these two flights, control and check points were used. RMSE were calculated. The radiometry was checked by a visual method and using the author's own algorithm for feature extraction (to define edges with subpixel accuracy). After initial pre-processing of data, the images were put together, and shown side by side
Extinction of Aversive Classically Conditioned Human Sexual Response
Brom, M.; Laan, E.; Everaerd, W.; Spinhoven, P.; Both, S.
INTRODUCTION: Research has shown that acquired subjective likes and dislikes are quite resistant to extinction. Moreover, studies on female sexual response demonstrated that diminished genital arousal and positive affect toward erotic stimuli due to aversive classical conditioning did not extinguish
SCIENCE WHERE CULTURE MATTERS: A NEO-CLASSICAL ...
Indian Academy of Sciences (India)
SCIENCE WHERE CULTURE MATTERS: A NEO-CLASSICAL APPROACH TO EXPLORE UNTAPPED BACTERIAL DIVERSITY. MILIND WATVE; Dept of Microbiology, Abasaheb Garware College, Pune. www.culturematters.org; * Life Research Foundation, Pune; * Evolvus Biotech Pvt. Ltd.,Pune ...
Classical and quantum dynamics from classical paths to path integrals
Dittrich, Walter
2017-01-01
Graduate students who wish to become familiar with advanced computational strategies in classical and quantum dynamics will find in this book both the fundamentals of a standard course and a detailed treatment of the time-dependent oscillator, Chern-Simons mechanics, the Maslov anomaly and the Berry phase, to name just a few topics. Well-chosen and detailed examples illustrate perturbation theory, canonical transformations and the action principle, and demonstrate the usage of path integrals. The fifth edition has been revised and enlarged to include chapters on quantum electrodynamics, in particular, Schwinger’s proper time method and the treatment of classical and quantum mechanics with Lie brackets and pseudocanonical transformations. It is shown that operator quantum electrodynamics can be equivalently described with c-numbers, as demonstrated by calculating the propagation function for an electron in a prescribed classical electromagnetic field.
Karlimah
2018-05-01
This study examines the application of classical music backsound in mathematics learning. The method used is quasi experimental design nonequivalent pretest-posttest control group in elementary school students in Tasikmalaya city, Indonesia. The results showed that classical music contributed significantly to the mathematical intelligence of elementary school students. The mathematical intelligence shown is in the cognitive ability ranging from the level of knowledge to evaluation. High level mathematical intelligence is shown by students in reading and writing integers with words and numbers. The low level of mathematical intelligence exists in projecting the story into a mathematical problem. The implication of this research is the use of classical music backsound on learning mathematics should pay attention to the level of difficulty of mathematics material being studied.
Does classical liberalism imply democracy?
Directory of Open Access Journals (Sweden)
David Ellerman
2015-12-01
Full Text Available There is a fault line running through classical liberalism as to whether or not democratic self-governance is a necessary part of a liberal social order. The democratic and non-democratic strains of classical liberalism are both present today—particularly in the United States. Many contemporary libertarians and neo-Austrian economists represent the non-democratic strain in their promotion of non-democratic sovereign city-states (start-up cities or charter cities. We will take the late James M. Buchanan as a representative of the democratic strain of classical liberalism. Since the fundamental norm of classical liberalism is consent, we must start with the intellectual history of the voluntary slavery contract, the coverture marriage contract, and the voluntary non-democratic constitution (or pactum subjectionis. Next we recover the theory of inalienable rights that descends from the Reformation doctrine of the inalienability of conscience through the Enlightenment (e.g. Spinoza and Hutcheson in the abolitionist and democratic movements. Consent-based governments divide into those based on the subjects’ alienation of power to a sovereign and those based on the citizens’ delegation of power to representatives. Inalienable rights theory rules out that alienation in favor of delegation, so the citizens remain the ultimate principals and the form of government is democratic. Thus the argument concludes in agreement with Buchanan that the classical liberal endorsement of sovereign individuals acting in the marketplace generalizes to the joint action of individuals as the principals in their own organizations.
Doing classical theology in context
Directory of Open Access Journals (Sweden)
Gerrit Neven
2007-05-01
Full Text Available This article is about doing classical theology in context. The weight of my argument is that classical text of Karl Barth’s theology is great intellectual text means: being addressed by this text in the context in which one lives. The basic keywords that constitute a rule for reading those texts are “equality”, “event” and “re-contextualisation”. The article contains two sections: The first section elaborates statements about the challenge of the event and the project of rereading classics by way of recontextualisation. The word “event” refers to true and innovating moments in history which one can share, or which one can betray. Classical texts always share in those liberative moments. The question then is in what sense do they present a challenge to the contemporary reader. The second section elaborates the position of man as central and all decisive for doing theology in context now. In this section, the author appeals for a renewal of the classical anthropology as an anthropology of hope. This anthropology contradicts postmodern concepts of otherness.
Classical approach in atomic physics
International Nuclear Information System (INIS)
Solov'ev, E.A.
2011-01-01
The application of a classical approach to various quantum problems - the secular perturbation approach to quantization of a hydrogen atom in external fields and a helium atom, the adiabatic switching method for calculation of a semiclassical spectrum of a hydrogen atom in crossed electric and magnetic fields, a spontaneous decay of excited states of a hydrogen atom, Gutzwiller's approach to Stark problem, long-lived excited states of a helium atom discovered with the help of Poincare section, inelastic transitions in slow and fast electron-atom and ion-atom collisions - is reviewed. Further, a classical representation in quantum theory is discussed. In this representation the quantum states are treated as an ensemble of classical states. This approach opens the way to an accurate description of the initial and final states in classical trajectory Monte Carlo (CTMC) method and a purely classical explanation of tunneling phenomenon. The general aspects of the structure of the semiclassical series such as renormalization group symmetry, criterion of accuracy and so on are reviewed as well. (author)
International Nuclear Information System (INIS)
Baran, V.
1995-01-01
This resume of the Ph.D. thesis has three main parts. In the first part a fourth order quadrupole boson Hamiltonian is semi classically treated through a time-dependent variational principle (TDVP), the variational states being of coherent type for the boson operators b 20 + and 1/√2 (b 22 + + b 2-2 + ). The static ground state is studied as a function of the parameters involved in the model Hamiltonian. Linearizing the classical equations of motion one obtains the RPA approach for the many boson correlations. There are two RPA roots which describe the beta and gamma vibrations, respectively. Several quantization procedures for both small and large amplitude regimes are discussed. The quantized Hamiltonians are compared with some others which were previously obtained by using different methods. A special attention is paid to the quantal states associated to some of the peaks appearing in the Fourier spectrum of the classical action density. Some of the quantal states exhibit a pronounced anharmonic structure. Therefore the procedure may be used for a unified description of small and large amplitude regimes. In the next part the semiclassical foundations of the Coherent State Model are established using the formalism elaborated in the previous section. In the third part the semiclassical treatment through a time-dependent variational principle (TDVP) of the fourth order quadrupole boson Hamiltonian H is continued. In the parameter space of H there are regions, conventionally called as 'nuclear phases', determining specific static properties. Several ground states corresponding to different equilibrium shapes are found as static solutions of classical equations of motion. The non-integrable system may follow a chaotic trajectory. The mechanism of destroying the tori bearing regular orbits and the onset of chaos may depend on nuclear phase. The regular and chaotic motions are analyzed in terms of Poincare sections and Lyapunov largest exponent. Specific features of
Classical wave experiments on chaotic scattering
International Nuclear Information System (INIS)
Kuhl, U; Stoeckmann, H-J; Weaver, R
2005-01-01
We review recent research on the transport properties of classical waves through chaotic systems with special emphasis on microwaves and sound waves. Inasmuch as these experiments use antennas or transducers to couple waves into or out of the systems, scattering theory has to be applied for a quantitative interpretation of the measurements. Most experiments concentrate on tests of predictions from random matrix theory and the random plane wave approximation. In all studied examples a quantitative agreement between experiment and theory is achieved. To this end it is necessary, however, to take absorption and imperfect coupling into account, concepts that were ignored in most previous theoretical investigations. Classical phase space signatures of scattering are being examined in a small number of experiments
Green’s functions in classical physics
Rother, Tom
2017-01-01
This book presents the Green’s function formalism in a basic way and demonstrates its usefulness for applications to several well-known problems in classical physics which are usually solved not by this formalism but other approaches. The book bridges the gap between applications of the Green’s function formalism in quantum physics and classical physics. This book is written as an introduction for graduate students and researchers who want to become more familiar with the Green’s function formalism. In 1828 George Green has published an essay that was unfortunately sunken into oblivion shortly after its publication. It was rediscovered only after several years by the later Lord Kelvin. But since this time, using Green’s functions for solving partial differential equations in physics has become an important mathematical tool. While the conceptual and epistemological importance of these functions were essentially discovered and discussed in modern physics - especially in quantum field theory and quantum...
The Diversity of Classical Archaeology
DEFF Research Database (Denmark)
, settlement patterns, landscape archaeology, historiography, and urban archaeology. Additionally, essays on topics such as the early Islamic period and portraiture in the Near East serve to broaden the themes encompassed by this work, and demonstrate the importance of interdisciplinary knowledge in the field......This book is the first volume in the series Studies in Classical Archaeology, founded and edited by professors of classical archaeology, Achim Lichtenberger and Rubina Raja. This volume sets out the agenda for this series. It achieves this by familiarizing readers with a wide range of themes...... and material groups, and highlighting them as core areas of traditional classical archaeology, despite the fact that some have hitherto been neglected. Themes presented in this volume include Greek and Roman portraiture and sculpture, iconography, epigraphy, archaeology, numismatics, the Mediterranean...
Classical Dimensional Transmutation and Confinement
Dvali, Gia; Mukhanov, Slava
2011-01-01
We observe that probing certain classical field theories by external sources uncovers the underlying renormalization group structure, including the phenomenon of dimensional transmutation, at purely-classical level. We perform this study on an example of $\\lambda\\phi^{4}$ theory and unravel asymptotic freedom and triviality for negative and positives signs of $\\lambda$ respectively. We derive exact classical $\\beta$ function equation. Solving this equation we find that an isolated source has an infinite energy and therefore cannot exist as an asymptotic state. On the other hand a dipole, built out of two opposite charges, has finite positive energy. At large separation the interaction potential between these two charges grows indefinitely as a distance in power one third.
Classical and quantum fingerprinting strategies
International Nuclear Information System (INIS)
Scott, A.; Walgate, J.; Sanders, B.
2005-01-01
Full text: Fingerprinting enables two parties to infer whether the messages they hold are the same or different when the cost of communication is high: each message is associated with a smaller fingerprint and comparisons between messages are made in terms of their fingerprints alone. When the two parties are forbidden access to a public coin, it is known that fingerprints composed of quantum information can be made exponentially smaller than those composed of classical information. We present specific constructions of classical fingerprinting strategies through the use of constant-weight codes and provide bounds on the worst-case error probability with the help of extremal set theory. These classical strategies are easily outperformed by quantum strategies constructed from line packings and equiangular tight frames. (author)
Foucault's pendulum, a classical analog for the electron spin state
Linck, Rebecca A.
Spin has long been regarded as a fundamentally quantum phenomena that is incapable of being described classically. To bridge the gap and show that aspects of spin's quantum nature can be described classically, this work uses a classical Lagrangian based on the coupled oscillations of Foucault's pendulum as an analog for the electron spin state in an external magnetic field. With this analog it is possible to demonstrate that Foucault's pendulum not only serves as a basis for explaining geometric phase, but is also a basis for reproducing a broad range of behavior from Zeeman-like frequency splitting to precession of the spin state. By demonstrating that unmeasured electron spin states can be fully described in classical terms, this research opens the door to using the tools of classical physics to examine an inherently quantum phenomenon.
Time Dependent Hartree Fock Equation: Gateway to Nonequilibrium Plasmas
International Nuclear Information System (INIS)
Dufty, James W.
2007-01-01
This is the Final Technical Report for DE-FG02-2ER54677 award 'Time Dependent Hartree Fock Equation - Gateway to Nonequilibrium Plasmas'. Research has focused on the nonequilibrium dynamics of electrons in the presence of ions, both via basic quantum theory and via semi-classical molecular dynamics (MD) simulation. In addition, fundamental notions of dissipative dynamics have been explored for models of grains and dust, and for scalar fields (temperature) in turbulent edge plasmas. The specific topics addressed were Quantum Kinetic Theory for Metallic Clusters, Semi-classical MD Simulation of Plasmas , and Effects of Dissipative Dynamics.
Optimum Onager: The Classical Mechanics of a Classical Siege Engine
Denny, Mark
2009-01-01
The onager is a throwing weapon of classical antiquity, familiar to both the ancient Greeks and Romans. Here we analyze the dynamics of onager operation and derive the optimum angle for launching a projectile to its maximum range. There is plenty of scope for further considerations about increasing onager range, and so by thinking about how this…
Overview of Classical Swine Fever (Hog Cholera, Classical Swine fever)
Classical swine fever is a contagious often fatal disease of pigs clinically characterized by high body temperature, lethargy, yellowish diarrhea, vomits and purple skin discoloration of ears, lower abdomen and legs. It was first described in the early 19th century in the USA. Later, a condition i...
Resonance phenomenon in classical cepheids
International Nuclear Information System (INIS)
Takeuti, Mine; Aikawa, Toshiki
1981-01-01
To investigate resonance phenomenon in classical cepheids, the non-linear radial oscillation of stars is studied based on the assumption that the non-adiabatic perturbation is expressed in terms of van der Pol's type damping. Two- and three-wave resonance in this system is applied to classical cepheids to describe their bump and double-mode behavior. The phase of bump and the depression of amplitude are explained for bump cepheids. The double-periodicity is shown by the enhancement of the third overtone in three-wave resonance. Non-linear effect on resonant period is also discussed briefly. (author)
Classical planning and causal implicatures
DEFF Research Database (Denmark)
Blackburn, Patrick Rowan; Benotti, Luciana
In this paper we motivate and describe a dialogue manager (called Frolog) which uses classical planning to infer causal implicatures. A causal implicature is a type of Gricean relation implicature, a highly context dependent form of inference. As we shall see, causal implicatures are important...... to generate clarification requests"; as a result we can model task-oriented dialogue as an interactive process locally structured by negotiation of the underlying task. We give several examples of Frolog-human dialog, discuss the limitations imposed by the classical planning paradigm, and indicate...
Classical resonances and quantum scarring
International Nuclear Information System (INIS)
Manderfeld, Christopher
2003-01-01
We study the correspondence between phase-space localization of quantum (quasi-)energy eigenstates and classical correlation decay, given by Ruelle-Pollicott resonances of the Frobenius-Perron operator. It will be shown that scarred (quasi-)energy eigenstates are correlated: pairs of eigenstates strongly overlap in phase space (scar in same phase-space regions) if the difference of their eigenenergies is close to the phase of a leading classical resonance. Phase-space localization of quantum states will be measured by L 2 norms of their Husimi functions
Classical solutions and extended supergravity
International Nuclear Information System (INIS)
de Alfaro, V.; Fubini, S.; Furlan, G.
1980-03-01
The existence and properties of classical solutions for gravity coupled to matter fields have been investigated previously with the limitation to conformally flat solutions. In the search for a guiding criterion to determine the form of the coupling among the fields, one is led to consider supersymmetric theories, and the question arises whether classical solutions persist in these models. It is found that a discrepancy persists between supergravity and standard meron solutions. Owing to the appearance of the scalar field, a new set of meron solutions exists for particular Lagrangian models. In conclusion, the form of solutions in Minkowski space is discussed
Indian Academy of Sciences (India)
Our primary source of information on Prof. Ruchi Ram Sahni is his typed autobiography, copies of which have been available with his descendants. Because of typing errors, illegibility, and other disabilities, their use had so far been limited. Now, his great-granddaughter, Neera Burra (whose article appears elsewhere.
Indian Academy of Sciences (India)
IAS Admin
gravitational acceleration, the physical properties of air and water, and so forth. ... system, I will consider aspects of the physical world and ask what organisms, ..... speed should have little or no direct effect on water loss by transpiration.
Indian Academy of Sciences (India)
IAS Admin
words, the origin (0;0) of the (x; y)-plane blows-up into the line x0 = 0 of the (x0 ... This is where I entered the picture. .... Especially I remember the tasty salads made with .... vacation cottage that I must do a better job in my introduction, because.
Indian Academy of Sciences (India)
would say various things to make me give up insisting upon my request. But as I was .... I then asked him not to leave the observatory till further orders, ... I have yet to mention another incident when under very strange circumstances, luck.
Matricial theory in classical photoelasticity
International Nuclear Information System (INIS)
Apostol, D.
1980-01-01
The matrix calculus in classical photoelasticity is used. Transfer functions for different polariscope arrangements are calculated. Linear polariscopes, circular polariscopes, double-exposure method to obtain isochromatics and Tardy and Senarmont method of measuring fractional relative retardations are analysed using coherency matrix formalism. (author)
Agglomeration Economies in Classical Music
DEFF Research Database (Denmark)
Borowiecki, Karol Jan
2015-01-01
This study investigates agglomeration effects for classical music production in a wide range of cities for a global sample of composers born between 1750 and 1899. Theory suggests a trade-off between agglomeration economies (peer effects) and diseconomies (peer crowding). I test this hypothesis...
Solved problems in classical electromagnetism
Franklin, Jerrold
2018-01-01
This original Dover publication is the companion to a new edition of the author's Classical Electromagnetism: Second Edition. The latter volume will feature only basic answers; this book will contain some problems from the reissue as well as many other new ones. All feature complete, worked-out solutions and form a valuable source of problem-solving material for students.
Doing classical theology in context
African Journals Online (AJOL)
p1243322
It is a critical concept, because it involves a break with ... question of the sense in which our context and culture have been interrupted by acts of ... challenge of reading a classical text is not only intellectual but also moral or existential. ..... and an opponent of pragmatic and relativistic conceptions8 I want to stress the.
Classical Music as Enforced Utopia
Leech-Wilkinson, Daniel
2016-01-01
In classical music composition, whatever thematic or harmonic conflicts may be engineered along the way, everything always turns out for the best. Similar utopian thinking underlies performance: performers see their job as faithfully carrying out their master's (the composer's) wishes. The more perfectly they represent them, the happier the…
Supersymmetric classical mechanics: free case
Energy Technology Data Exchange (ETDEWEB)
Rodrigues, R. de Lima [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)]|[Paraiba Univ., Cajazeiras, PB (Brazil). Dept. de Ciencias Exatas e da Natureza]. E-mail: rafael@cfp.ufpb.br; Almeida, W. Pires de [Paraiba Univ., Cajazeiras, PB (Brazil). Dept. de Ciencias Exatas e da Natureza; Fonseca Neto, I. [Paraiba Univ., Campina Grande, PB (Brazil). Dept. de Fisica
2001-06-01
We present a review work on Supersymmetric Classical Mechanics in the context of a Lagrangian formalism, with N = 1-supersymmetry. We show that the N = 1 supersymmetry does not allow the introduction of a potencial energy term depending on a single commuting supercoordinate, {phi}(t;{theta}). (author)
Teaching Classical Mechanics Using Smartphones
Chevrier, Joel; Madani, Laya; Ledenmat, Simon; Bsiesy, Ahmad
2013-01-01
A number of articles published in this column have dealt with topics in classical mechanics. This note describes some additional examples employing a smartphone and the new software iMecaProf. Steve Jobs presented the iPhone as "perfect for gaming." Thanks to its microsensors connected in real time to the numerical world, physics…
Neo-classical impurity transport
International Nuclear Information System (INIS)
Stringer, T.E.
The neo-classical theory for impurity transport in a toroidal plasma is outlined, and the results discussed. A general account is given of the impurity behaviour and its dependence on collisionality. The underlying physics is described with special attention to the role of the poloidal rotation
Malpetti, Daniele; Roscilde, Tommaso
2017-02-01
The mean-field approximation is at the heart of our understanding of complex systems, despite its fundamental limitation of completely neglecting correlations between the elementary constituents. In a recent work [Phys. Rev. Lett. 117, 130401 (2016), 10.1103/PhysRevLett.117.130401], we have shown that in quantum many-body systems at finite temperature, two-point correlations can be formally separated into a thermal part and a quantum part and that quantum correlations are generically found to decay exponentially at finite temperature, with a characteristic, temperature-dependent quantum coherence length. The existence of these two different forms of correlation in quantum many-body systems suggests the possibility of formulating an approximation, which affects quantum correlations only, without preventing the correct description of classical fluctuations at all length scales. Focusing on lattice boson and quantum Ising models, we make use of the path-integral formulation of quantum statistical mechanics to introduce such an approximation, which we dub quantum mean-field (QMF) approach, and which can be readily generalized to a cluster form (cluster QMF or cQMF). The cQMF approximation reduces to cluster mean-field theory at T =0 , while at any finite temperature it produces a family of systematically improved, semi-classical approximations to the quantum statistical mechanics of the lattice theory at hand. Contrary to standard MF approximations, the correct nature of thermal critical phenomena is captured by any cluster size. In the two exemplary cases of the two-dimensional quantum Ising model and of two-dimensional quantum rotors, we study systematically the convergence of the cQMF approximation towards the exact result, and show that the convergence is typically linear or sublinear in the boundary-to-bulk ratio of the clusters as T →0 , while it becomes faster than linear as T grows. These results pave the way towards the development of semiclassical numerical
From classical to quantum plasmonics: Classical emitter and SPASER
Balykin, V. I.
2018-02-01
The key advantage of plasmonics is in pushing our control of light down to the nanoscale. It is possible to envision lithographically fabricated plasmonic devices for future quantum information processing or cryptography at the nanoscale in two dimensions. A first step in this direction is a demonstration of a highly efficient nanoscale light source. Here we demonstrate two types of nanoscale sources of optical fields: 1) the classical metallic nanostructure emitter and 2) the plasmonic nanolaser - SPASER.
Classical trajectory methods in molecular collisions
International Nuclear Information System (INIS)
Porter, R.N.; Raff, L.M.
1976-01-01
The discussion of classical trajectory methods in molecular collisions includes classical dynamics, Hamiltonian mechanics, classical scattering cross sections and rate coefficients, statistical averaging, the selection of initial states, integration of equations of motion, analysis of final states, consecutive collisions, and the prognosis for classical molecular scattering calculations. 61 references
Ehlers-Danlos syndrome, classical type.
Bowen, Jessica M; Sobey, Glenda J; Burrows, Nigel P; Colombi, Marina; Lavallee, Mark E; Malfait, Fransiska; Francomano, Clair A
2017-03-01
Classical EDS is a heritable disorder of connective tissue. Patients are affected with joint hypermobility, skin hyperextensibilty, and skin fragility leading to atrophic scarring and significant bruising. These clinical features suggest consideration of the diagnosis which then needs to be confirmed, preferably by genetic testing. The most recent criteria for the diagnosis of EDS were devised in Villefranche in 1997. [Beighton et al. (1998); Am J Med Genet 77:31-37]. The aims set out in the Villefranche Criteria were: to enable diagnostic uniformity for clinical and research purposes, to understand the natural history of each subtype of EDS, to inform management and genetic counselling, and to identify potential areas of research. The authors recognized that the criteria would need updating, but viewed the Villefranche nosology as a good starting point. Since 1997, there have been major advances in the molecular understanding of classical EDS. Previous question marks over genetic heterogeneity have been largely surpassed by evidence that abnormalities in type V collagen are the cause. Advances in molecular testing have made it possible to identify the causative mutation in the majority of patients. This has aided the further clarification of this diagnosis. The aim of this literature review is to summarize the current knowledge and highlight areas for future research. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
From classical to quantum chaos
International Nuclear Information System (INIS)
Zaslavsky, G.M.
1991-01-01
The analysis is done for the quantum properties of systems that possess dynamical chaos in classical limit. Two main topics are considered: (i) the problem of quantum macroscopical description of the system and the Ehrenfest-Einstein problem of the validity of the classical approximation; and (ii) the problem of levels spacing distribution for the nonintegrable case. For the first topic the method of projecting on the coherent states base is considered and the ln 1/(h/2π) time for the quasiclassical approximation breaking is described. For the second topic the discussion of GOE and non-GOE distributions is done and estimations and simulations for the non-GOE case are reviewed. (author). 44 refs, 2 figs
Classical theory of algebraic numbers
Ribenboim, Paulo
2001-01-01
Gauss created the theory of binary quadratic forms in "Disquisitiones Arithmeticae" and Kummer invented ideals and the theory of cyclotomic fields in his attempt to prove Fermat's Last Theorem These were the starting points for the theory of algebraic numbers, developed in the classical papers of Dedekind, Dirichlet, Eisenstein, Hermite and many others This theory, enriched with more recent contributions, is of basic importance in the study of diophantine equations and arithmetic algebraic geometry, including methods in cryptography This book has a clear and thorough exposition of the classical theory of algebraic numbers, and contains a large number of exercises as well as worked out numerical examples The Introduction is a recapitulation of results about principal ideal domains, unique factorization domains and commutative fields Part One is devoted to residue classes and quadratic residues In Part Two one finds the study of algebraic integers, ideals, units, class numbers, the theory of decomposition, iner...
Quantum Models of Classical World
Directory of Open Access Journals (Sweden)
Petr Hájíček
2013-02-01
Full Text Available This paper is a review of our recent work on three notorious problems of non-relativistic quantum mechanics: realist interpretation, quantum theory of classical properties, and the problem of quantum measurement. A considerable progress has been achieved, based on four distinct new ideas. First, objective properties are associated with states rather than with values of observables. Second, all classical properties are selected properties of certain high entropy quantum states of macroscopic systems. Third, registration of a quantum system is strongly disturbed by systems of the same type in the environment. Fourth, detectors must be distinguished from ancillas and the states of registered systems are partially dissipated and lost in the detectors. The paper has two aims: a clear explanation of all new results and a coherent and contradiction-free account of the whole quantum mechanics including all necessary changes of its current textbook version.
Classical music and the teeth.
Eramo, Stefano; Di Biase, Mary Jo; De Carolis, Carlo
2013-01-01
Teeth and their pathologies are frequent themes in classical music. The teeth have inspired popular songwriters such as Thomas Crecquillon, Carl Loewe, Amilcare Ponchielli & Christian Sinding; as well as composers whose works are still played all over the world, such as Robert Schumann and Jacques Offenbach. This paper examines several selections in which the inspiring theme is the teeth and the pain they can cause, from the suffering of toothache, to the happier occasion of a baby's first tooth.
Psoriasis: classical and emerging comorbidities*
de Oliveira, Maria de Fátima Santos Paim; Rocha, Bruno de Oliveira; Duarte, Gleison Vieira
2015-01-01
Psoriasis is a chronic inflammatory systemic disease. Evidence shows an association of psoriasis with arthritis, depression, inflammatory bowel disease and cardiovascular diseases. Recently, several other comorbid conditions have been proposed as related to the chronic inflammatory status of psoriasis. The understanding of these conditions and their treatments will certainly lead to better management of the disease. The present article aims to synthesize the knowledge in the literature about the classical and emerging comorbidities related to psoriasis. PMID:25672294
Quantum Mechanics as Classical Physics
Sebens, CT
2015-01-01
Here I explore a novel no-collapse interpretation of quantum mechanics which combines aspects of two familiar and well-developed alternatives, Bohmian mechanics and the many-worlds interpretation. Despite reproducing the empirical predictions of quantum mechanics, the theory looks surprisingly classical. All there is at the fundamental level are particles interacting via Newtonian forces. There is no wave function. However, there are many worlds.
Classical counterexamples to Bell's inequalities
International Nuclear Information System (INIS)
Orlov, Yuri F.
2002-01-01
This paper shows that a classical system containing a conventional yes/no decision-making component can behave like a quantum system of spin measurements in many ways (although it lacks a wave function) when, in principle, there are no deterministic decision procedures to govern the decision making, and when probabilistic decision procedures consistent with the system are introduced. Most notably, the system violates Bell's inequalities. Moreover, since the system is simple and macroscopic, its similarities to quantum systems arguably provide an insight into quantum mechanics and, in particular, EPR experiments. Thus, from the qualitative correspondences, decisions↔quantum measurements and the impossibility of deterministic decision procedures↔quantum noncommutativity, we conclude that the violation of Bell's inequalities in quantum mechanics does not require the existence of an unknown nonclassical nonlocality. It can merely be a result of local noncommutativity combined with nonlocalities of the classical type. The proposed classical decision-making system is a nonquantum theoretical construct possessing complementarity features in Bohr's sense
Classical optics and curved spaces
International Nuclear Information System (INIS)
Bailyn, M.; Ragusa, S.
1976-01-01
In the eikonal approximation of classical optics, the unit polarization 3-vector of light satisfies an equation that depends only on the index, n, of refraction. It is known that if the original 3-space line element is d sigma 2 , then this polarization direction propagates parallely in the fictitious space n 2 d sigma 2 . Since the equation depends only on n, it is possible to invent a fictitious curved 4-space in which the light performs a null geodesic, and the polarization 3-vector behaves as the 'shadow' of a parallely propagated 4-vector. The inverse, namely, the reduction of Maxwell's equation, on a curve 'dielectric free) space, to a classical space with dielectric constant n=(-g 00 ) -1 / 2 is well known, but in the latter the dielectric constant epsilon and permeability μ must also equal (-g 00 ) -1 / 2 . The rotation of polarization as light bends around the sun by utilizing the reduction to the classical space, is calculated. This (non-) rotation may then be interpreted as parallel transport in the 3-space n 2 d sigma 2 [pt
A Walk Through an American Classic
Directory of Open Access Journals (Sweden)
Emma Gage
2012-12-01
Full Text Available The music of Walt Disney’s classic films was written by a number of hand-picked composers who, working with Disney, ingeniously crafted the music to fit animation and bring musical inspiration to the homes of viewers leaving America and the world with a beloved legacy. Though Walt Disney was a cartoonist and not a musician, music was given a distinct, almost central, role in the creation of his cartoons. Special techniques such as Mickey-mousing or the click track were developed by composers and used to synchronize this music and animation. These processes really began with Disney and have formed the basis for all music synchronized to cartoon animation. From the very beginning with Mickey Mouse, to The Silly Symphonies, to the beloved classic Disney movies music has been an ever-present and developing center. Walt Disney, though not a composer himself, hired a number of key composers from which we have many cherished melodies. Unlike most other cartoons Disney’s were focused on using music of the classical style rather than the popular style. The music from a number of classical composers was used or drawn upon as a model. Disney had a special purpose for the music in his animated films. Most of his films contained a story other than the music, but his movie Fantasia really seeks to find the purpose music itself has with visual interpretation. College students have done research on these ideas of simply listening to music or listening while seeing an image. All of Disney’s animated films would not be the classics they are without the music that holds them together. Disney music has become recognized as its own individual art form. It has inspired America to dream and to think more deeply than realized. Walt Disney’s indirect effect on music history may be considered a stretch, but there is no doubt that the music developed through Disney Bros. has left an inspiration on the hearts of Americans.
RAACFDb: Rheumatoid arthritis ayurvedic classical formulations database.
Mohamed Thoufic Ali, A M; Agrawal, Aakash; Sajitha Lulu, S; Mohana Priya, A; Vino, S
2017-02-02
In the past years, the treatment of rheumatoid arthritis (RA) has undergone remarkable changes in all therapeutic modes. The present newfangled care in clinical research is to determine and to pick a new track for better treatment options for RA. Recent ethnopharmacological investigations revealed that traditional herbal remedies are the most preferred modality of complementary and alternative medicine (CAM). However, several ayurvedic modes of treatments and formulations for RA are not much studied and documented from Indian traditional system of medicine. Therefore, this directed us to develop an integrated database, RAACFDb (acronym: Rheumatoid Arthritis Ayurvedic Classical Formulations Database) by consolidating data from the repository of Vedic Samhita - The Ayurveda to retrieve the available formulations information easily. Literature data was gathered using several search engines and from ayurvedic practitioners for loading information in the database. In order to represent the collected information about classical ayurvedic formulations, an integrated database is constructed and implemented on a MySQL and PHP back-end. The database is supported by describing all the ayurvedic classical formulations for the treatment rheumatoid arthritis. It includes composition, usage, plant parts used, active ingredients present in the composition and their structures. The prime objective is to locate ayurvedic formulations proven to be quite successful and highly effective among the patients with reduced side effects. The database (freely available at www.beta.vit.ac.in/raacfdb/index.html) hopefully enables easy access for clinical researchers and students to discover novel leads with reduced side effects. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Quantum-Classical Correspondence: Dynamical Quantization and the Classical Limit
International Nuclear Information System (INIS)
Turner, L
2004-01-01
In only 150 pages, not counting appendices, references, or the index, this book is one author's perspective of the massive theoretical and philosophical hurdles in the no-man's-land separating the classical and quantum domains of physics. It ends with him emphasizing his own theoretical contribution to this area. In his own words, he has attempted to answer: 1. How can we obtain the quantum dynamics of open systems initially described by the equations of motion of classical physics (quantization process) 2. How can we retrieve classical dynamics from the quantum mechanical equations of motion by means of a classical limiting process (dequantization process). However, this monograph seems overly ambitious. Although the publisher's description refers to this book as an accessible entre, we find that this author scrambles too hastily over the peaks of information that are contained in his large collection of 272 references. Introductory motivating discussions are lacking. Profound ideas are glossed over superficially and shoddily. Equations morph. But no new convincing understanding of the physical world results. The author takes the viewpoint that physical systems are always in interaction with their environment and are thus not isolated and, therefore, not Hamiltonian. This impels him to produce a method of quantization of these stochastic systems without the need of a Hamiltonian. He also has interest in obtaining the classical limit of the quantized results. However, this reviewer does not understand why one needs to consider open systems to understand quantum-classical correspondence. The author demonstrates his method using various examples of the Smoluchowski form of the Fokker--Planck equation. He then renders these equations in a Wigner representation, uses what he terms an infinitesimality condition, and associates with a constant having the dimensions of an action. He thereby claims to develop master equations, such as the Caldeira-Leggett equation, without
Intuitionism vs. classicism a mathematical attack on classical logic
Haverkamp, Nick
2015-01-01
In the early twentieth century, the Dutch mathematician L.E.J. Brouwer launched a powerful attack on the prevailing mathematical methods and theories. He developed a new kind of constructive mathematics, called intuitionism, which seems to allow for a rigorous refutation of widely accepted mathematical assumptions including fundamental principles of classical logic. Following an intense mathematical debate esp. in the 1920s, Brouwer's revolutionary criticism became a central philosophical concern in the 1970s, when Michael Dummett tried to substantiate it with meaning-theoretic considerations.
Classical and quantum dynamics from classical paths to path integrals
Dittrich, Walter
2016-01-01
Graduate students who want to become familiar with advanced computational strategies in classical and quantum dynamics will find here both the fundamentals of a standard course and a detailed treatment of the time-dependent oscillator, Chern-Simons mechanics, the Maslov anomaly and the Berry phase, to name a few. Well-chosen and detailed examples illustrate the perturbation theory, canonical transformations, the action principle and demonstrate the usage of path integrals. This new edition has been revised and enlarged with chapters on quantum electrodynamics, high energy physics, Green’s functions and strong interaction.
Quantum-classical correspondence for the inverted oscillator
Maamache, Mustapha; Ryeol Choi, Jeong
2017-11-01
While quantum-classical correspondence for a system is a very fundamental problem in modern physics, the understanding of its mechanism is often elusive, so the methods used and the results of detailed theoretical analysis have been accompanied by active debate. In this study, the differences and similarities between quantum and classical behavior for an inverted oscillator have been analyzed based on the description of a complete generalized Airy function-type quantum wave solution. The inverted oscillator model plays an important role in several branches of cosmology and particle physics. The quantum wave packet of the system is composed of many sub-packets that are localized at different positions with regular intervals between them. It is shown from illustrations of the probability density that, although the quantum trajectory of the wave propagation is somewhat different from the corresponding classical one, the difference becomes relatively small when the classical excitation is sufficiently high. We have confirmed that a quantum wave packet moving along a positive or negative direction accelerates over time like a classical wave. From these main interpretations and others in the text, we conclude that our theory exquisitely illustrates quantum and classical correspondence for the system, which is a crucial concept in quantum mechanics. Supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2016R1D1A1A09919503)
Classical limit for quantum mechanical energy eigenfunctions
International Nuclear Information System (INIS)
Sen, D.; Sengupta, S.
2004-01-01
The classical limit problem is discussed for the quantum mechanical energy eigenfunctions using the Wentzel-Kramers-Brillouin approximation, free from the problem at the classical turning points. A proper perspective of the whole issue is sought to appreciate the significance of the discussion. It is observed that for bound states in arbitrary potential, appropriate limiting condition is definable in terms of a dimensionless classical limit parameter leading smoothly to all observable classical results. Most important results are the emergence of classical phase space, keeping the observable distribution functions non-zero only within the so-called classical region at the limit point and resolution of some well-known paradoxes. (author)
The Relation between Classical and Quantum Electrodynamics
Directory of Open Access Journals (Sweden)
Mario Bacelar Valente
2011-01-01
Full Text Available Quantum electrodynamics presents intrinsic limitations in the description of physical processes that make it impossible to recover from it the type of description we have in classical electrodynamics. Hence one cannot consider classical electrodynamics as reducing to quantum electrodynamics and being recovered from it by some sort of limiting procedure. Quantum electrodynamics has to be seen not as an more fundamental theory, but as an upgrade of classical electrodynamics, which permits an extension of classical theory to the description of phenomena that, while being related to the conceptual framework of the classical theory, cannot be addressed from the classical theory.
Casimir effect: The classical limit
International Nuclear Information System (INIS)
Feinberg, J.; Mann, A.; Revzen, M.
2001-01-01
We analyze the high temperature (or classical) limit of the Casimir effect. A useful quantity which arises naturally in our discussion is the 'relative Casimir energy', which we define for a configuration of disjoint conducting boundaries of arbitrary shapes, as the difference of Casimir energies between the given configuration and a configuration with the same boundaries infinitely far apart. Using path integration techniques, we show that the relative Casimir energy vanishes exponentially fast in temperature. This is consistent with a simple physical argument based on Kirchhoff's law. As a result the 'relative Casimir entropy', which we define in an obviously analogous manner, tends, in the classical limit, to a finite asymptotic value which depends only on the geometry of the boundaries. Thus the Casimir force between disjoint pieces of the boundary, in the classical limit, is entropy driven and is governed by a dimensionless number characterizing the geometry of the cavity. Contributions to the Casimir thermodynamical quantities due to each individual connected component of the boundary exhibit logarithmic deviations in temperature from the behavior just described. These logarithmic deviations seem to arise due to our difficulty to separate the Casimir energy (and the other thermodynamical quantities) from the 'electromagnetic' self-energy of each of the connected components of the boundary in a well defined manner. Our approach to the Casimir effect is not to impose sharp boundary conditions on the fluctuating field, but rather take into consideration its interaction with the plasma of 'charge carriers' in the boundary, with the plasma frequency playing the role of a physical UV cutoff. This also allows us to analyze deviations from a perfect conductor behavior
Classical Syllogisms in Logic Teaching
DEFF Research Database (Denmark)
Øhrstrøm, Peter; Sandborg-Petersen, Ulrik; Thorvaldsen, Steinar
2013-01-01
This paper focuses on the challenges of introducing classical syllogisms in university courses in elementary logic and human reasoning. Using a program written in Prolog+CG, some empirical studies have been carried out involving three groups of students in Denmark; one group of philosophy students...... have a tendency correctly to assess valid syllogisms as such more often than correctly assessing invalid syllogisms as such. It is also investigated to what extent the students have improved their skills in practical reasoning by attending the logic courses. Finally, some open questions regarding...
Metastable gravity on classical defects
International Nuclear Information System (INIS)
Ringeval, Christophe; Rombouts, Jan-Willem
2005-01-01
We discuss the realization of metastable gravity on classical defects in infinite-volume extra dimensions. In dilatonic Einstein gravity, it is found that the existence of metastable gravity on the defect core requires violation of the dominant energy condition for codimension N c =2 defects. This is illustrated with a detailed analysis of a six-dimensional hyperstring minimally coupled to dilaton gravity. We present the general conditions under which a codimension N c >2 defect admits metastable modes, and find that they differ from lower codimensional models in that, under certain conditions, they do not require violation of energy conditions to support quasilocalized gravity
Nonlinear classical theory of electromagnetism
International Nuclear Information System (INIS)
Pisello, D.
1977-01-01
A topological theory of electric charge is given. Einstein's criteria for the completion of classical electromagnetic theory are summarized and their relation to quantum theory and the principle of complementarity is indicated. The inhibiting effect that this principle has had on the development of physical thought is discussed. Developments in the theory of functions on nonlinear spaces provide the conceptual framework required for the completion of electromagnetism. The theory is based on an underlying field which is a continuous mapping of space-time into points on the two-sphere. (author)
Classics in Chemical Neuroscience: Haloperidol.
Tyler, Marshall W; Zaldivar-Diez, Josefa; Haggarty, Stephen J
2017-03-15
The discovery of haloperidol catalyzed a breakthrough in our understanding of the biochemical basis of schizophrenia, improved the treatment of psychosis, and facilitated deinstitutionalization. In doing so, it solidified the role for chemical neuroscience as a means to elucidate the molecular underpinnings of complex neuropsychiatric disorders. In this Review, we will cover aspects of haloperidol's synthesis, manufacturing, metabolism, pharmacology, approved and off-label indications, and adverse effects. We will also convey the fascinating history of this classic molecule and the influence that it has had on the evolution of neuropsychopharmacology and neuroscience.
Quantum effects in biological electron transfer
Czech Academy of Sciences Publication Activity Database
de la Lande, A.; Babcock, N. S.; Řezáč, Jan; Levy, B.; Sanders, B. C.; Salahub, D.
2012-01-01
Roč. 14, č. 17 (2012), s. 5902-5918 ISSN 1463-9076 Institutional research plan: CEZ:AV0Z40550506 Keywords : electron transfer * tunnelling * decoherence * semi-classical molecular dynamics * density functional theory Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.829, year: 2012
Pseudoclassical fermionic model and classical solutions
International Nuclear Information System (INIS)
Smailagic, A.
1981-08-01
We study classical limit of fermionic fields seen as Grassmann variables and deduce the proper quantization prescription using Dirac's method for constrained systems and investigate quantum meaning of classical solutions for the Thirring model. (author)
Physiological characteristics of classical ballet.
Schantz, P G; Astrand, P O
1984-10-01
The aerobic and anaerobic energy yield during professional training sessions ("classes") of classical ballet as well as during rehearsed and performed ballets has been studied by means of oxygen uptake, heart rate, and blood lactate concentration determinations on professional ballet dancers from the Royal Swedish Ballet in Stockholm. The measured oxygen uptake during six different normal classes at the theatre averaged about 35-45% of the maximal oxygen uptake, and the blood lactate concentration averaged 3 mM (N = 6). During 10 different solo parts of choreographed dance (median length = 1.8 min) representative for moderately to very strenuous dance, an average oxygen uptake (measured during the last minute) of 80% of maximum and blood lactate concentration of 10 mM was measured (N = 10). In addition, heart rate registrations from soloists in different ballets during performance and final rehearsals frequently indicated a high oxygen uptake relative to maximum and an average blood lactate concentration of 11 mM (N = 5). Maximal oxygen uptake, determined in 1971 (N = 11) and 1983 (N = 13) in two different groups of dancers, amounted to on the average 51 and 56 ml X min-1 X kg-1 for the females and males, respectively. In conclusion, classical ballet is a predominantly intermittent type of exercise. In choreographed dance each exercise period usually lasts only a few minutes, but can be very demanding energetically, while during the dancers' basic training sessions, the energy yield is low.
Modular forms a classical approach
Cohen, Henri
2017-01-01
The theory of modular forms is a fundamental tool used in many areas of mathematics and physics. It is also a very concrete and "fun" subject in itself and abounds with an amazing number of surprising identities. This comprehensive textbook, which includes numerous exercises, aims to give a complete picture of the classical aspects of the subject, with an emphasis on explicit formulas. After a number of motivating examples such as elliptic functions and theta functions, the modular group, its subgroups, and general aspects of holomorphic and nonholomorphic modular forms are explained, with an emphasis on explicit examples. The heart of the book is the classical theory developed by Hecke and continued up to the Atkin-Lehner-Li theory of newforms and including the theory of Eisenstein series, Rankin-Selberg theory, and a more general theory of theta series including the Weil representation. The final chapter explores in some detail more general types of modular forms such as half-integral weight, Hilbert, Jacob...
Teaching classical mechanics using smartphones
Chevrier, Joel; Madani, Laya; Ledenmat, Simon; Bsiesy, Ahmad
2013-09-01
A number of articles published in this column have dealt with topics in classical mechanics. This note describes some additional examples employing a smartphone and the new software iMecaProf.4 Steve Jobs presented the iPhone as "perfect for gaming."5 Thanks to its microsensors connected in real time to the numerical world, physics teachers could add that smartphones are "perfect for teaching science." The software iMecaProf displays in real time the measured data on a screen. The visual representation is built upon the formalism of classical mechanics. iMecaProf receives data 100 times a second from iPhone sensors through a Wi-Fi connection using the application Sensor Data.6 Data are the three components of the acceleration vector in the smartphone frame and smartphone's orientation through three angles (yaw, pitch, and roll). For circular motion (uniform or not), iMecaProf uses independent measurements of the rotation angle θ, the angular speed dθ/dt, and the angular acceleration d2θ/dt2.
De la Flor-Martínez, Maria; Galindo-Moreno, Pablo; Sánchez-Fernández, Elena; Piattelli, Adriano; Cobo, Manuel Jesus; Herrera-Viedma, Enrique
2016-10-01
The study of classic papers permits analysis of the past, present, and future of a specific area of knowledge. This type of analysis is becoming more frequent and more sophisticated. Our objective was to use the H-classics method, based on the h-index, to analyze classic papers in Implant Dentistry, Periodontics, and Oral Surgery (ID, P, and OS). First, an electronic search of documents related to ID, P, and OS was conducted in journals indexed in Journal Citation Reports (JCR) 2014 within the category 'Dentistry, Oral Surgery & Medicine'. Second, Web of Knowledge databases were searched using Mesh terms related to ID, P, and OS. Finally, the H-classics method was applied to select the classic articles in these disciplines, collecting data on associated research areas, document type, country, institutions, and authors. Of 267,611 documents related to ID, P, and OS retrieved from JCR journals (2014), 248 were selected as H-classics. They were published in 35 journals between 1953 and 2009, most frequently in the Journal of Clinical Periodontology (18.95%), the Journal of Periodontology (18.54%), International Journal of Oral and Maxillofacial Implants (9.27%), and Clinical Oral Implant Research (6.04%). These classic articles derived from the USA in 49.59% of cases and from Europe in 47.58%, while the most frequent host institution was the University of Gothenburg (17.74%) and the most frequent authors were J. Lindhe (10.48%) and S. Socransky (8.06%). The H-classics approach offers an objective method to identify core knowledge in clinical disciplines such as ID, P, and OS. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Classical correlations, Bell inequalities, and communication complexity
Energy Technology Data Exchange (ETDEWEB)
Wilms, Johannes; Alber, Gernot [Institut fuer Angewandte Physik, Technische Universitaet Darmstadt, D-64289 Darmstadt (Germany); Percival, Ian C. [Department of Physics, Univ. of London (United Kingdom)
2007-07-01
A computer program is presented which is capable of exploring generalizations of Bell-type inequalities for arbitrary numbers of classical inputs and outputs. Thereby, polytopes can be described which represent classical local realistic theories, classical theories without signaling, or classical theories with explicit signaling. These latter polytopes may also be of interest for exploring basic problems of communication complexity. As a first application the influence of non-perfect detectors is discussed in simple Bell experiments.
Origin of classical structure in the Universe
Energy Technology Data Exchange (ETDEWEB)
Kiefer, Claus [Institut fuer Theoretische Physik, Universitaet zu Koeln, Zuelpicher Str. 77, 50937 Cologne (Germany); Lohmar, Ingo [Institut fuer Theoretische Physik, Universitaet zu Koeln, Zuelpicher Str. 77, 50937 Cologne (Germany); Polarski, David [Laboratoire de Physique Theorique et Astroparticules, UMR 5207 CNRS, Universite de Montpellier II, 34095 Montpellier (France); Starobinsky, Alexei A [Landau Institute for Theoretical Physics, Kosygina St. 2, Moscow 119334 (Russian Federation)
2007-05-15
We address the quantum-to-classical transition for primordial fluctuations, that is, the emergence of classical stochastic properties for these fluctuations. We discuss in particular the entanglement entropy for these fluctuations, the decoherence time, and the question of the classical basis (pointer basis) for them. The decoherence time for modes outside the Hubble scale is set by the Hubble parameter. The classical states are narrow Gaussians in the field amplitude.
Local quantum channels preserving classical correlations
International Nuclear Information System (INIS)
Guo Zhihua; Cao Huaixin
2013-01-01
The aim of this paper is to discuss local quantum channels that preserve classical correlations. First, we give two equivalent characterizations of classical correlated states. Then we obtain the relationships among classical correlation-preserving local quantum channels, commutativity-preserving local quantum channels and commutativity-preserving quantum channels on each subsystem. Furthermore, for a two-qubit system, we show the general form of classical correlation-preserving local quantum channels. (paper)
Markkinointiviestintäsuunnitelma : Classic Coffee Oy
Eerola, Laura
2015-01-01
Opinnäytetyön aiheena oli laatia markkinointiviestintäsuunnitelma kalenterivuodelle 2016 vuosikellon muodossa, toimintansa jo vakiinnuttaneelle Classic Coffee Oy:lle. Classic Coffee Oy on vuonna 2011 perustettu, Tampereella toimiva kahvila-alan yritys joka tarjoaa lounaskahvilatoiminnan lisäksi laadukkaita konditoria-palveluita, yritys- ja kokoustarjoiluja sekä tilavuokrausta. Classic Coffee Oy:llä on yksi kahvila, Classic Coffee Tampella. Kahvila sijaitsee Tampellassa, Tampereen keskustan vä...
About the modern house - and the classical
DEFF Research Database (Denmark)
Hauberg, Jørgen
2010-01-01
In text and illustrations describes the classical house and the classical city, represented by Andrea Palladio (1508-80), and the modern house, the modern city and building task, represented by Le Corbusier (1857-1965).......In text and illustrations describes the classical house and the classical city, represented by Andrea Palladio (1508-80), and the modern house, the modern city and building task, represented by Le Corbusier (1857-1965)....
Diminuendo: Classical Music and the Academy
Asia, Daniel
2010-01-01
How is the tradition of Western classical music faring on university campuses? Before answering this question, it is necessary to understand what has transpired with classical music in the wider culture, as the relationship between the two is so strong. In this article, the author discusses how classical music has taken a big cultural hit in…
Introduction to Classical and Quantum Harmonic Oscillators
International Nuclear Information System (INIS)
Latal, H
1997-01-01
As the title aptly states, this book deals with harmonic oscillators of various kinds, from classical mechanical and electrical oscillations up to quantum oscillations. It is written in a lively language, and occasional interspersed anecdotes make the reading of an otherwise mathematically oriented text quite a pleasure. Although the author claims to have written an 'elementary introduction', it is certainly necessary to have a good deal of previous knowledge in physics (mechanics, electrodynamics, quantum theory), electrical engineering and, of course, mathematics in order to follow the general line of his arguments. The book begins with a thorough treatment of classical oscillators (free, damped, forced) that is followed by an elaboration on Fourier analysis. Lagrange and Hamilton formalisms are then introduced before the problem of coupled oscillations is attacked. A chapter on statistical perspectives leads over to the final discussion of quantum oscillations. With the book comes a diskette containing a number of worksheets (Microsoft Excel) that can be used by the reader for instant visualization to get a better qualitative and quantitative understanding of the material. To the reviewer it seems difficult to pinpoint exactly the range of prospective readership of the book. It can certainly not be intended as a textbook for students, but rather as a reference book for teachers of physics or researchers, who want to look up one or other aspect of harmonic oscillations, for which purpose the diskette represents a very valuable tool. (book review)
ENVIRONMENTALISM AND CLASSIC PARADIGMS OF INTERNATIONAL RELATIONS
Directory of Open Access Journals (Sweden)
D. D. Miniaeva
2014-06-01
Full Text Available This article examines an environmentalism integration process into Three classical paradigms of international relations theory (Liberalism, Realism and Marxism into Three classical paradigms of international relations theory (Liberalism, Realism and Marxism. The main purpose of this study is to reveal the result of this integration. Methods used in this article include analysis and comparison of "ecological" paradigms on selected parameters (the nature of international relations, actors, targets, tools, processes. Results of research show that the beginning of the XXI century is distinguished by the development of new types of political concepts that explain interaction of elements in modern international relations in the area of environmental protection. The reason of these changes lies in the phenomena of environmentalism integration into Three paradigms of international relations. However, we cannot say that any of the examined paradigms accumulated all features of environmentalism without their modification. Better to say, it's rather similar to adaptation of environmental ideas. Therefore, to understand modern international relations processes, it is necessary to take into account their environmental element. Purchase on Elibrary.ru > Buy nowDOI: http://dx.doi.org/10.12731/2070-7568-2014-3-4
Theoretical physics 1 classical mechanics
Nolting, Wolfgang
2016-01-01
This textbook offers a clear and comprehensive introduction to classical mechanics, one of the core components of undergraduate physics courses. The book starts with a thorough introduction to the mathematical tools needed, to make this textbook self-contained for learning. The second part of the book introduces the mechanics of the free mass point and details conservation principles. The third part expands the previous to mechanics of many particle systems. Finally the mechanics of the rigid body is illustrated with rotational forces, inertia and gyroscope movement. Ideally suited to undergraduate students in their first year, the book is enhanced throughout with learning features such as boxed inserts and chapter summaries, with key mathematical derivations highlighted to aid understanding. The text is supported by numerous worked examples and end of chapter problem sets. About the Theoretical Physics series Translated from the renowned and highly successful German editions, the eight volumes of this series...
DOE Fundamentals Handbook: Classical Physics
International Nuclear Information System (INIS)
1992-06-01
The Classical Physics Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of physical forces and their properties. The handbook includes information on the units used to measure physical properties; vectors, and how they are used to show the net effect of various forces; Newton's Laws of motion, and how to use these laws in force and motion applications; and the concepts of energy, work, and power, and how to measure and calculate the energy involved in various applications. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility systems and equipment
Bettini, Alessandro
This first volume covers the mechanics of point particles, gravitation, extended systems (starting from the two-body system), the basic concepts of relativistic mechanics and the mechanics of rigid bodies and fluids. The four-volume textbook, which covers electromagnetism, mechanics, fluids and thermodynamics, and waves and light, is designed to reflect the typical syllabus during the first two years of a calculus-based university physics program. Throughout all four volumes, particular attention is paid to in-depth clarification of conceptual aspects, and to this end the historical roots of the principal concepts are traced. Writings by the founders of classical mechanics, G. Galilei and I. Newton, are reproduced, encouraging students to consult them. Emphasis is also consistently placed on the experimental basis of the concepts, highlighting the experimental nature of physics. Whenever feasible at the elementary level, concepts relevant to more advanced courses in modern physics are included. Each chapter b...
Classical imaging with undetected light
Cardoso, A. C.; Berruezo, L. P.; Ávila, D. F.; Lemos, G. B.; Pimenta, W. M.; Monken, C. H.; Saldanha, P. L.; Pádua, S.
2018-03-01
We obtained the phase and intensity images of an object by detecting classical light which never interacted with it. With a double passage of a pump and a signal laser beams through a nonlinear crystal, we observe interference between the two idler beams produced by stimulated parametric down conversion. The object is placed in the amplified signal beam after its first passage through the crystal and the image is observed in the interference of the generated idler beams. High contrast images can be obtained even for objects with small transmittance coefficient due to the geometry of the interferometer and to the stimulated parametric emission. Like its quantum counterpart, this three-color imaging concept can be useful when the object must be probed with light at a wavelength for which detectors are not available.
Introducing Newton and classical physics
Rankin, William
2002-01-01
The rainbow, the moon, a spinning top, a comet, the ebb and flood of the oceans ...a falling apple. There is only one universe and it fell to Isaac Newton to discover its secrets. Newton was arguably the greatest scientific genius of all time, and yet he remains a mysterious figure. Written and illustrated by William Rankin, "Introducting Newton and Classical Physics" explains the extraordinary ideas of a man who sifted through the accumulated knowledge of centuries, tossed out mistaken beliefs, and single-handedly made enormous advances in mathematics, mechanics and optics. By the age of 25, entirely self-taught, he had sketched out a system of the world. Einstein's theories are unthinkable without Newton's founding system. He was also a secret heretic, a mystic and an alchemist, the man of whom Edmund Halley said "Nearer to the gods may no man approach!". This is an ideal companion volume to "Introducing Einstein".
Classical electromagnetism in a nutshell
Garg, Anupam
2012-01-01
This graduate-level physics textbook provides a comprehensive treatment of the basic principles and phenomena of classical electromagnetism. While many electromagnetism texts use the subject to teach mathematical methods of physics, here the emphasis is on the physical ideas themselves. Anupam Garg distinguishes between electromagnetism in vacuum and that in material media, stressing that the core physical questions are different for each. In vacuum, the focus is on the fundamental content of electromagnetic laws, symmetries, conservation laws, and the implications for phenomena such as radiation and light. In material media, the focus is on understanding the response of the media to imposed fields, the attendant constitutive relations, and the phenomena encountered in different types of media such as dielectrics, ferromagnets, and conductors. The text includes applications to many topical subjects, such as magnetic levitation, plasmas, laser beams, and synchrotrons.
Classical Cosmology Through Animation Stories
Mijic, Milan; Kang, E. Y. E.; Longson, T.; State LA SciVi Project, Cal
2010-05-01
Computer animations are a powerful tool for explanation and communication of ideas, especially to a younger generation. Our team completed a three part sequence of short, computer animated stories about the insight and discoveries that lead to the understanding of the overall structure of the universe. Our principal characters are Immanuel Kant, Henrietta Leavitt, and Edwin Hubble. We utilized animations to model and visualize the physical concepts behind each discovery and to recreate the characters, locations, and flavor of the time. The animations vary in length from 6 to 11 minutes. The instructors or presenters may wish to utilize them separately or together. The animations may be used for learning classical cosmology in a visual way in GE astronomy courses, in pre-college science classes, or in public science education setting.
Quantum and classical gauge symmetries
International Nuclear Information System (INIS)
Fujikawa, Kazuo; Terashima, Hiroaki
2001-01-01
The use of the mass term of the gauge field as a gauge fixing term, which was discussed by Zwanziger, Parrinello and Jona-Lasinio in a large mass limit, is related to the non-linear gauge by Dirac and Nambu. We have recently shown that this use of the mass term as a gauge fixing term is in fact identical to the conventional local Faddeev-Popov formula without taking a large mass limit, if one takes into account the variation of the gauge field along the entire gauge orbit. This suggests that the classical massive vector theory, for example, could be re-interpreted as a gauge invariant theory with a gauge fixing term added in suitably quantized theory. As for massive gauge particles, the Higgs mechanics, where the mass term is gauge invariant, has a more intrinsic meaning. We comment on several implications of this observation. (author)
From classical to quantum fields
Baulieu, Laurent; Sénéor, Roland
2017-01-01
Quantum Field Theory has become the universal language of most modern theoretical physics. This introductory textbook shows how this beautiful theory offers the correct mathematical framework to describe and understand the fundamental interactions of elementary particles. The book begins with a brief reminder of basic classical field theories, electrodynamics and general relativity, as well as their symmetry properties, and proceeds with the principles of quantisation following Feynman's path integral approach. Special care is used at every step to illustrate the correct mathematical formulation of the underlying assumptions. Gauge theories and the problems encountered in their quantisation are discussed in detail. The last chapters contain a full description of the Standard Model of particle physics and the attempts to go beyond it, such as grand unified theories and supersymmetry. Written for advanced undergraduate and beginning graduate students in physics and mathematics, the book could also serve as a re...
Classical and quantum thermal physics
Prasad, R
2016-01-01
Covering essential areas of thermal physics, this book includes kinetic theory, classical thermodynamics, and quantum thermodynamics. The text begins by explaining fundamental concepts of the kinetic theory of gases, viscosity, conductivity, diffusion, and the laws of thermodynamics and their applications. It then goes on to discuss applications of thermodynamics to problems of physics and engineering. These applications are explained with the help of P-V and P-S-H diagrams where necessary and are followed by a large number of solved examples and unsolved exercises. The book includes a dedicated chapter on the applications of thermodynamics to chemical reactions. Each application is explained by taking the example of an appropriate chemical reaction, where all technical terms are explained and complete mathematical derivations are worked out in steps starting from the first principle.
State-dependent classical potentials
International Nuclear Information System (INIS)
D'Amico, M.
2001-01-01
As alternative treatment to the potential operators of standard quantum mechanics is presented. The method is derived from Bohm's mechanics. The operator scalar (V) and vector (A) potential functions are replaced by a quantum potential. It is argued that the classical potential is a special limiting case of a more general quantum potential. The theory is illustrated by deriving an equivalent single-particle equation for the i-th particle of an n-body Bohmian system. The resulting effective state-dependent potential holds the interaction between the single-particle self-wave ψ s and the environment wave ψ e of the n - 1 remaining particles. The effective state-dependent potential is offered as a resolution to the Aharonov-Bohm effect where the phase difference is shown to result from the presence of ψ e . Finally, the interaction between ψ s and ψ e is illustrated graphically
On causal nonrelativistic classical electrodynamics
International Nuclear Information System (INIS)
Goedecke, G.H.
1984-01-01
The differential-difference (DD) motion equations of the causal nonrelativistic classical electrodynamics developed by the author in 1975 are shown to possess only nonrunaway, causal solutions with no discontinuities in particle velocity or position. As an example, the DD equation solution for the problem of an electromagnetic shock incident on an initially stationary charged particle is contrasted with the standard Abraham-Lorentz equation solution. The general Cauchy problem for these DD motion equations is discussed. In general, in order to uniquely determine a solution, the initial data must be more detailed than the standard Cauchy data of initial position and velocity. Conditions are given under which the standard Cauchy data will determine the DD equation solutions to sufficient practical accuracy
Hydrogen: Beyond the Classic Approximation
International Nuclear Information System (INIS)
Scivetti, Ivan
2003-01-01
The classical nucleus approximation is the most frequently used approach for the resolution of problems in condensed matter physics.However, there are systems in nature where it is necessary to introduce the nuclear degrees of freedom to obtain a correct description of the properties.Examples of this, are the systems with containing hydrogen.In this work, we have studied the resolution of the quantum nuclear problem for the particular case of the water molecule.The Hartree approximation has been used, i.e. we have considered that the nuclei are distinguishable particles.In addition, we have proposed a model to solve the tunneling process, which involves the resolution of the nuclear problem for configurations of the system away from its equilibrium position
Quantum classical correspondence in nonrelativistic electrodynamics
International Nuclear Information System (INIS)
Ritchie, B.; Weatherford, C.A.
1999-01-01
A form of classical electrodynamic field exists which gives exact agreement with the operator field of quantum electrodynamics (QED) for the Lamb shift of a harmonically bound point electron. Here it is pointed out that this form of classical theory, with its physically acceptable interpretation, is the result of an unconventional resolution of a mathematically ambiguous term in classical field theory. Finally, a quantum classical correspondence principle is shown to exist in the sense that the classical field and expectation value of the QED operator field are identical, if retardation is neglected in the latter
Classical model of intermediate statistics
International Nuclear Information System (INIS)
Kaniadakis, G.
1994-01-01
In this work we present a classical kinetic model of intermediate statistics. In the case of Brownian particles we show that the Fermi-Dirac (FD) and Bose-Einstein (BE) distributions can be obtained, just as the Maxwell-Boltzmann (MD) distribution, as steady states of a classical kinetic equation that intrinsically takes into account an exclusion-inclusion principle. In our model the intermediate statistics are obtained as steady states of a system of coupled nonlinear kinetic equations, where the coupling constants are the transmutational potentials η κκ' . We show that, besides the FD-BE intermediate statistics extensively studied from the quantum point of view, we can also study the MB-FD and MB-BE ones. Moreover, our model allows us to treat the three-state mixing FD-MB-BE intermediate statistics. For boson and fermion mixing in a D-dimensional space, we obtain a family of FD-BE intermediate statistics by varying the transmutational potential η BF . This family contains, as a particular case when η BF =0, the quantum statistics recently proposed by L. Wu, Z. Wu, and J. Sun [Phys. Lett. A 170, 280 (1992)]. When we consider the two-dimensional FD-BE statistics, we derive an analytic expression of the fraction of fermions. When the temperature T→∞, the system is composed by an equal number of bosons and fermions, regardless of the value of η BF . On the contrary, when T=0, η BF becomes important and, according to its value, the system can be completely bosonic or fermionic, or composed both by bosons and fermions
Classical foundations of quantum logic
International Nuclear Information System (INIS)
Garola, C.
1991-01-01
The author constructs a language L for a classical first-order predicate calculus with monadic predicates only, extended by means of a family of statistical quantifiers. Then, a formal semantic model M is put forward for L which is compatible with a physical interpretation and embodies a truth theory which provides the statistical quantifiers with properties that fit their interpretation; in this framework, the truth mode of physical laws is suitably characterized and a probability-frequency correlation principle is established. By making use of L and M, a set of basic physical laws is stated that hold both in classical physics (CP) and in quantum physics (QP), which allow the selection of suitable subsets of primitive predicates of L and the introduction on these subsets of binary relations. Two languages L E x and L E S are constructed that can be mapped into L; the mapping induces on them mathematical structures, some kind of truth function, an interpretation. The formulas of L E S can be endowed with two different interpretations as statements about the frequency of some physical property in some class (state) of physical objects; consequently, a two-valued truth function and a multivalued fuzzy-truth function are defined on L E S . In all cases the algebras of propositions of these 'logics' are complete ortho-complemented lattices isomorphic to (E E , prec). These results hold both in CP and in QP; further physical assumptions endow the lattice (E E , prec), hence L E x and L E s , with further properties, such as distributivity in CP and weak modularity and covering law in QP. In the latter case, L E x and L E s , together with their interpretations, can be considered different models of the same basic mathematical structure, and can be identified with standard (elementary) quantum logics
Zwitters: Particles between quantum and classical
International Nuclear Information System (INIS)
Wetterich, C.
2012-01-01
We describe both quantum particles and classical particles in terms of a classical statistical ensemble, with a probability distribution in phase space. By use of a wave function in phase space both can be treated in the same quantum formalism. Quantum particles are characterized by a specific choice of observables and time evolution of the probability density. Then interference and tunneling are found within classical statistics. Zwitters are (effective) one-particle states for which the time evolution interpolates between quantum and classical particles. Experimental bounds on a small parameter can test quantum mechanics. -- Highlights: ► Quantum particles can be described within classical statistics. ► Classical particles are formulated in quantum formalism. ► Zwitters interpolate between classical and quantum particles. ► Zwitters allow for quantitative tests of quantum mechanics. ► Zwitters could be effective one-particle descriptions of droplets.
Mathematical omnibus thirty lectures on classic mathematics
Fuchs, Dmitry; Fuchs, Dmitry
2007-01-01
The book consists of thirty lectures on diverse topics, covering much of the mathematical landscape rather than focusing on one area. The reader will learn numerous results that often belong to neither the standard undergraduate nor graduate curriculum and will discover connections between classical and contemporary ideas in algebra, combinatorics, geometry, and topology. The reader's effort will be rewarded in seeing the harmony of each subject. The common thread in the selected subjects is their illustration of the unity and beauty of mathematics. Most lectures contain exercises, and solutions or answers are given to selected exercises. A special feature of the book is an abundance of drawings (more than four hundred), artwork by an accomplished artist, and about a hundred portraits of mathematicians. Almost every lecture contains surprises for even the seasoned researcher.
Semiclassical description of scattering with internal degrees of freedom
International Nuclear Information System (INIS)
Cruz-Barrios, S.; Gomez-Camacho, J.
1998-01-01
The scattering of systems with internal degrees of freedom is studied in the semi-classical approximation. It is found that a special set of states, named coherent internal states, are specially relevant for the semi-classical treatment. A classical trajectory is defined for each coherent internal state. The semi-classical expressions obtained satisfy the superposition principle and are valid for arbitrary coupling strength. (orig.)
Could a Mobile-Assisted Learning System Support Flipped Classrooms for Classical Chinese Learning?
Wang, Y.-H.
2016-01-01
In this study, the researcher aimed to develop a mobile-assisted learning system and to investigate whether it could promote teenage learners' classical Chinese learning through the flipped classroom approach. The researcher first proposed the structure of the Cross-device Mobile-Assisted Classical Chinese (CMACC) system according to the pilot…
SCIENCE WHERE CULTURE MATTERS: A NEO-CLASSICAL ...
Indian Academy of Sciences (India)
Table of contents. SCIENCE WHERE CULTURE MATTERS: A NEO-CLASSICAL APPROACH TO EXPLORE UNTAPPED BACTERIAL DIVERSITY · UNDER GRADUATE RESEARCH An alternative model of doing science · THE EXPANSE OF LIFE · HOW MANY SP. OF BACTERIA IN 1 g SOIL? TORSVIK ET AL 1990.
Making the Transition from Classical to Quantum Physics
Dutt, Amit
2011-01-01
This paper reports on the nature of the conceptual understandings developed by Year 12 Victorian Certificate of Education (VCE) physics students as they made the transition from the essentially deterministic notions of classical physics, to interpretations characteristic of quantum theory. The research findings revealed the fact that the…
Psychosocial developmental milestones in men with classic galactosemia
Gubbels, Cynthia Sophia; Maurice-Stam, Heleen; Berry, Gerard Thomas; Bosch, Annet Maria; Waisbren, Susan; Rubio-Gozalbo, Maria Estela; Grootenhuis, Martha Alexandra
2011-01-01
Patients with classic galactosemia suffer from several long term effects of their disease. Research in a group of mainly female patients has shown that these patients may also have a developmental delay with regard to their social aptitude. To study if male galactosemia patients achieve psychosocial
Assessing difference between classical test theory and item ...
African Journals Online (AJOL)
Assessing difference between classical test theory and item response theory methods in scoring primary four multiple choice objective test items. ... All research participants were ranked on the CTT number correct scores and the corresponding IRT item pattern scores from their performance on the PRISMADAT. Wilcoxon ...
Extinction of aversive classically conditioned human sexual response
Brom, Mirte; Laan, Ellen; Everaerd, Walter; Spinhoven, Philip; Both, Stephanie
2015-01-01
Research has shown that acquired subjective likes and dislikes are quite resistant to extinction. Moreover, studies on female sexual response demonstrated that diminished genital arousal and positive affect toward erotic stimuli due to aversive classical conditioning did not extinguish during an
Principles of maximally classical and maximally realistic quantum ...
Indian Academy of Sciences (India)
Principles of maximally classical and maximally realistic quantum mechanics. S M ROY. Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005, India. Abstract. Recently Auberson, Mahoux, Roy and Singh have proved a long standing conjecture of Roy and Singh: In 2N-dimensional phase space, ...
Ordering in classical Coulombic systems
International Nuclear Information System (INIS)
Schiffer, J. P.
1998-01-01
The author discusses the properties of classical Coulombic matter at low temperatures. It has been well known for some time [1,2] that infinite Coulombic matter will crystallize in body-centered cubic form when the quantity Λ (the dimensionless ratio of the average two-particle Coulomb energy to the kinetic energy per particle) is larger than approximately175. But the systems of such particles that have been produced in the laboratory in ion traps, or ion beams, are finite with surfaces defined by the boundary conditions that have to be satisfied. This results in ion clouds with sharply defined curved surfaces, and interior structures that show up as a set of concentric layers that are parallel to the outer surface. The ordering does not appear to be cubic, but the charges on each shell exhibit a ''hexatic'' pattern of equilateral triangles that is the characteristic of liquid crystals. The curvature of the surfaces prevents the structures on successive shells from interlocking in any simple fashion. This class of structures was first found in simulations [3] and later in experiments [4
Relaxation properties in classical diamagnetism
Carati, A.; Benfenati, F.; Galgani, L.
2011-06-01
It is an old result of Bohr that, according to classical statistical mechanics, at equilibrium a system of electrons in a static magnetic field presents no magnetization. Thus a magnetization can occur only in an out of equilibrium state, such as that produced through the Foucault currents when a magnetic field is switched on. It was suggested by Bohr that, after the establishment of such a nonequilibrium state, the system of electrons would quickly relax back to equilibrium. In the present paper, we study numerically the relaxation to equilibrium in a modified Bohr model, which is mathematically equivalent to a billiard with obstacles, immersed in a magnetic field that is adiabatically switched on. We show that it is not guaranteed that equilibrium is attained within the typical time scales of microscopic dynamics. Depending on the values of the parameters, one has a relaxation either to equilibrium or to a diamagnetic (presumably metastable) state. The analogy with the relaxation properties in the Fermi Pasta Ulam problem is also pointed out.
Classical randomness in quantum measurements
International Nuclear Information System (INIS)
D'Ariano, Giacomo Mauro; Presti, Paoloplacido Lo; Perinotti, Paolo
2005-01-01
Similarly to quantum states, also quantum measurements can be 'mixed', corresponding to a random choice within an ensemble of measuring apparatuses. Such mixing is equivalent to a sort of hidden variable, which produces a noise of purely classical nature. It is then natural to ask which apparatuses are indecomposable, i.e. do not correspond to any random choice of apparatuses. This problem is interesting not only for foundations, but also for applications, since most optimization strategies give optimal apparatuses that are indecomposable. Mathematically the problem is posed describing each measuring apparatus by a positive operator-valued measure (POVM), which gives the statistics of the outcomes for any input state. The POVMs form a convex set, and in this language the indecomposable apparatuses are represented by extremal points-the analogous of 'pure states' in the convex set of states. Differently from the case of states, however, indecomposable POVMs are not necessarily rank-one, e.g. von Neumann measurements. In this paper we give a complete classification of indecomposable apparatuses (for discrete spectrum), by providing different necessary and sufficient conditions for extremality of POVMs, along with a simple general algorithm for the decomposition of a POVM into extremals. As an interesting application, 'informationally complete' measurements are analysed in this respect. The convex set of POVMs is fully characterized by determining its border in terms of simple algebraic properties of the corresponding POVMs
Microscopic theory of nuclear collective dynamics
International Nuclear Information System (INIS)
Sakata, Fumihiko; Marumori, Toshio; Hashimoto, Yukio; Tsukuma, Hidehiko; Yamamoto, Yoshifumi; Iwasawa, Kazuo.
1990-10-01
A recent development of the INS-TSUKUBA joint research project on large-amplitude collective motion is summarized by putting special emphasis on an inter-relationship between quantum chaos and nuclear spectroscopy. Aiming at introducing various concepts used in this lecture, we start with recapitulating the semi-classical theory of nuclear collective dynamics formulated within the time-dependent Hartree-Fock (TDHF) theory. The central part of the semi-classical theory is provided by the self-consistent collective coordinate (SCC) method which has been developed to properly take account of the non-linear dynamics specific for the finite many-body quantum system. A decisive role of the level crossing dynamics on the order-to-chaos transition of collective motion is discussed in detail. Extending the basic idea of the semi-classical theory, we discuss a full quantum theory of nuclear collective dynamics which allows us to properly define a concept of the quantum integrability as well as the quantum chaoticity for each eigenfunction. The lecture is arranged so as to clearly show the similar structure between the semi-classical and quantum theories of nuclear collective dynamics. Using numerical calculations, we illustrate what the quantum chaos for each eigenfunction means and relate it to the usual definition of quantum chaos for nearest neighbor level spacing statistics based on the random matrix theory. (author)
Lectures on classical and quantum theory of fields
Arodz, Henryk
2017-01-01
This textbook addresses graduate students starting to specialize in theoretical physics. It provides didactic introductions to the main topics in the theory of fields, while taking into account the contemporary view of the subject. The student will find concise explanations of basic notions essential for applications of the theory of fields as well as for frontier research in theoretical physics. One third of the book is devoted to classical fields. Each chapter contains exercises of varying degree of difficulty with hints or solutions, plus summaries and worked examples as useful. It aims to deliver a unique combination of classical and quantum field theory in one compact course.
Institute of Scientific and Technical Information of China (English)
卫艳蕾
2014-01-01
运用舞蹈生态学的研究方法，把翼城花鼓和万荣花鼓置于相互联系、相互作用的系统中进行宏观的、多维的综合考察。以翼城花鼓和万荣花鼓音乐节奏中的典型节奏型为文本，从基础单位典型舞畴入手，对其节奏型进行特征提取，进行简繁适度的因子分解和有效的综合分析，寻求与比较临汾翼城花鼓与运城万荣花鼓两者的典型舞畴节奏型异同。%Taking flower-drumin Yicheng of Linfen and Wanrong of Yuncheng in southern part of shanxi as research object, using choreoecology as research method, this paper puts flower-drumin Yicheng and Wanrong in a interrelative and interactive systemto survey it in a macroscopic and dimensional way. Taking classic rhythmtype in music rhythm of Yicheng flower-drum and Wanrong flower-drumas text, starting with typical dance domain as basic unit ,simplifying useless things ,draw ing the classic dance domain rhythmtype as characteristics ,making a comprehensive analysis in a proper factorial and effective way, the study aims to seek for similarities and differences in classic dance domain rhythmtype by comparing flow-er-drumin Yicheng of Linfen with Wanrong of Yuncheng.
Classical region of a trapped Bose gas
Energy Technology Data Exchange (ETDEWEB)
Blakie, P Blair [Jack Dodd Centre for Photonics and Ultra-Cold Atoms, University of Otago, Dunedin (New Zealand); Davis, Matthew J [ARC Centre of Excellence for Quantum-Atom Optics, School of Physical Sciences, University of Queensland, Brisbane, QLD 4072 (Australia)
2007-06-14
The classical region of a Bose gas consists of all single particle modes that have a high average occupation and are well described by a classical field. Highly occupied modes only occur in massive Bose gases at ultra-cold temperatures, in contrast to the photon case where there are highly occupied modes at all temperatures. For the Bose gas the number of these modes is dependent on the temperature, the total number of particles and their interaction strength. In this paper, we characterize the classical region of a harmonically trapped Bose gas over a wide parameter regime. We use a Hartree-Fock approach to account for the effects of interactions, which we observe to significantly change the classical region as compared to the idealized case. We compare our results to full classical field calculations and show that the Hartree-Fock approach provides a qualitatively accurate description of a classical region for the interacting gas.
The relation between classical and quantum mechanics
International Nuclear Information System (INIS)
Taylor, Peter.
1984-01-01
The thesis examines the relationship between classical and quantum mechanics from philosophical, mathematical and physical standpoints. Arguments are presented in favour of 'conjectural realism' in scientific theories, distinguished by explicit contextual structure and empirical testability. The formulations of classical and quantum mechanics, based on a general theory of mechanics is investigated, as well as the mathematical treatments of these subjects. Finally the thesis questions the validity of 'classical limits' and 'quantisations' in intertheoretic reduction. (UK)
Classical Mechanics as Nonlinear Quantum Mechanics
International Nuclear Information System (INIS)
Nikolic, Hrvoje
2007-01-01
All measurable predictions of classical mechanics can be reproduced from a quantum-like interpretation of a nonlinear Schroedinger equation. The key observation leading to classical physics is the fact that a wave function that satisfies a linear equation is real and positive, rather than complex. This has profound implications on the role of the Bohmian classical-like interpretation of linear quantum mechanics, as well as on the possibilities to find a consistent interpretation of arbitrary nonlinear generalizations of quantum mechanics
Classical logic and logicism in human thought
Elqayam, Shira
2012-01-01
This chapter explores the role of classical logic as a theory of human reasoning. I distinguish between classical logic as a normative, computational and algorithmic system, and review its role is theories of human reasoning since the 1960s. The thesis I defend is that psychological theories have been moving further and further away from classical logic on all three levels. I examine some prominent example of logicist theories, which incorporate logic in their psychological account, includin...
Connections between classical and parametric network entropies.
Directory of Open Access Journals (Sweden)
Matthias Dehmer
Full Text Available This paper explores relationships between classical and parametric measures of graph (or network complexity. Classical measures are based on vertex decompositions induced by equivalence relations. Parametric measures, on the other hand, are constructed by using information functions to assign probabilities to the vertices. The inequalities established in this paper relating classical and parametric measures lay a foundation for systematic classification of entropy-based measures of graph complexity.
Classical ultraviolet photoelectron spectroscopy of polymers
International Nuclear Information System (INIS)
Salaneck, W.R.
2009-01-01
Although X-ray photoelectron spectroscopy of polymers was well established by Clark and coworkers in the 1970s, ultraviolet photoelectron spectroscopy of polymer films, was developed later. Previous to the 1970s, the first attempts to use ultraviolet light on polymer films took the form of appearance potential (valence band edge) measurements. Only some years later could the full valence band region of thin polymer films, including insulating polymers, semiconducting polymers and electrically conducting polymers. The development of what might be termed 'classical ultraviolet photoelectron spectroscopy' of polymer films may be loosely based upon a variety of issues, including adapting thin polymer film technology to ultra high vacuum studies, the widespread use of helium resonance lamps for studies of solid surfaces, the combined advent of practical and sufficient theoretical-computational methods. The advent of, and the use of, easily available synchrotron radiation for multi-photon spectroscopies, nominally in the area of the near UV, is not included in the term 'classical'. At the same time, electrically conducting polymers were discovered, leading to applications of the corresponding semiconducting polymers, which added technologically driven emphasis to this development of ultraviolet photoelectron spectroscopy for polymer materials. This paper traces a limited number of highlights in the evolution of ultraviolet photoelectron spectroscopy of polymers, from the 1970s through to 2008. Also, since this issue is dedicated to Prof. Kazuhiko Seki, who has been a friend and competitor for over two decades, the author relies on some of Prof. Seki's earlier research, unpublished, on who-did-what-first. Prof. Seki's own contributions to the field, however, are discussed in other articles in this issue.
Lectures on classical and quantum theory of fields
Energy Technology Data Exchange (ETDEWEB)
Arodz, Henryk; Hadasz, Leszek [Jagiellonian Univ., Krakow (Poland). Inst. Physics
2010-07-01
This textbook on classical and quantum theory of fields addresses graduate students starting to specialize in theoretical physics. It provides didactic introductions to the main topics in the theory of fields, while taking into account the contemporary view of the subject. The student will find concise explanations of basic notions essential for applications of the theory of fields as well as for frontier research in theoretical physics. One third of the book is devoted to classical fields. Each chapter contains exercises of varying degree of difficulty with hints or solutions, plus summaries and worked examples as useful. The textbook is based on lectures delivered to students of theoretical physics at Jagiellonian University. It aims to deliver a unique combination of classical and quantum field theory in one compact course. (orig.)
Lectures on classical and quantum theory of fields
International Nuclear Information System (INIS)
Arodz, Henryk; Hadasz, Leszek
2010-01-01
This textbook on classical and quantum theory of fields addresses graduate students starting to specialize in theoretical physics. It provides didactic introductions to the main topics in the theory of fields, while taking into account the contemporary view of the subject. The student will find concise explanations of basic notions essential for applications of the theory of fields as well as for frontier research in theoretical physics. One third of the book is devoted to classical fields. Each chapter contains exercises of varying degree of difficulty with hints or solutions, plus summaries and worked examples as useful. The textbook is based on lectures delivered to students of theoretical physics at Jagiellonian University. It aims to deliver a unique combination of classical and quantum field theory in one compact course. (orig.)
Lectures on Classical and Quantum Theory of Fields
Arodź, Henryk
2010-01-01
This textbook on classical and quantum theory of fields addresses graduate students starting to specialize in theoretical physics. It provides didactic introductions to the main topics in the theory of fields, while taking into account the contemporary view of the subject. The student will find concise explanations of basic notions essential for applications of the theory of fields as well as for frontier research in theoretical physics. One third of the book is devoted to classical fields. Each chapter contains exercises of varying degree of difficulty with hints or solutions, plus summaries and worked examples as useful. The textbook is based on lectures delivered to students of theoretical physics at Jagiellonian University. It aims to deliver a unique combination of classical and quantum field theory in one compact course.
Locking classical correlations in quantum States.
DiVincenzo, David P; Horodecki, Michał; Leung, Debbie W; Smolin, John A; Terhal, Barbara M
2004-02-13
We show that there exist bipartite quantum states which contain a large locked classical correlation that is unlocked by a disproportionately small amount of classical communication. In particular, there are (2n+1)-qubit states for which a one-bit message doubles the optimal classical mutual information between measurement results on the subsystems, from n/2 bits to n bits. This phenomenon is impossible classically. However, states exhibiting this behavior need not be entangled. We study the range of states exhibiting this phenomenon and bound its magnitude.
Seven steps towards the classical world
International Nuclear Information System (INIS)
Allori, Valia; Duerr, Detlef; Goldstein, Shelly; Zanghi, Nino
2002-01-01
Classical physics is about real objects, like apples falling from trees, whose motion is governed by Newtonian laws. In standard quantum mechanics only the wavefunctions or the results of measurements exist, and to answer the question of how the classical world can be part of the quantum world is a rather formidable task. However, this is not the case for Bohmian mechanics which, like classical mechanics, is a theory about real objects. In Bohmian terms, the problem of the classical limit becomes very simple: when do the Bohmian trajectories look Newtonian?
Listening to classical music ameliorates unilateral neglect after stroke.
Tsai, Pei-Luen; Chen, Mei-Ching; Huang, Yu-Ting; Lin, Keh-Chung; Chen, Kuan-Lin; Hsu, Yung-Wen
2013-01-01
OBJECTIVE. We determined whether listening to excerpts of classical music ameliorates unilateral neglect (UN) in stroke patients. METHOD. In this within-subject study, we recruited and separately tested 16 UN patients with a right-hemisphere stroke under three conditions within 1 wk. In each condition, participants were asked to complete three subtests of the Behavioral Inattention Test while listening to classical music, white noise, or nothing. All conditions and the presentation of the tests were counterbalanced across participants. Visual analog scales were used to provide self-reported ratings of arousal and mood. RESULTS. Participants generally had the highest scores under the classical music condition and the lowest scores under the silence condition. In addition, most participants rated their arousal as highest after listening to classical music. CONCLUSION. Listening to classical music may improve visual attention in stroke patients with UN. Future research with larger study populations is necessary to validate these findings. Copyright © 2013 by the American Occupational Therapy Association, Inc.
On the co-creation of classical and modern physics.
Staley, Richard
2005-12-01
While the concept of "classical physics" has long framed our understanding of the environment from which modern physics emerged, it has consistently been read back into a period in which the physicists concerned initially considered their work in quite other terms. This essay explores the shifting currency of the rich cultural image of the classical/ modern divide by tracing empirically different uses of "classical" within the physics community from the 1890s to 1911. A study of fin-de-siècle addresses shows that the earliest general uses of the concept proved controversial. Our present understanding of the term was in large part shaped by its incorporation (in different ways) within the emerging theories of relativity and quantum theory--where the content of "classical" physics was defined by proponents of the new. Studying the diverse ways in which Boltzmann, Larmor, Poincaré, Einstein, Minkowski, and Planck invoked the term "classical" will help clarify the critical relations between physicists' research programs and their use of worldview arguments in fashioning modern physics.
International Nuclear Information System (INIS)
Gervais, J.L.
1993-01-01
By analyzing the extrinsic geometry of two dimensional surfaces chirally embedded in C P n (the C P n W-surface), we give exact treatments in various aspects of the classical W-geometry in the conformal gauge: First, the basis of tangent and normal vectors are defined at regular points of the surface, such that their infinitesimal displacements are given by connections which coincide with the vector potentials of the (conformal) A n -Toda Lax pair. Since the latter is known to be intrinsically related with the W symmetries, this gives the geometrical meaning of the A n W-Algebra. Second, W-surfaces are put in one-to-one correspondence with solutions of the conformally-reduced WZNW model, which is such that the Toda fields give the Cartan part in the Gauss decomposition of its solutions. Third, the additional variables of the Toda hierarchy are used as coordinates of C P n . This allows us to show that W-transformations may be extended as particular diffeomorphisms of this target-space. Higher-dimensional generalizations of the WZNW equations are derived and related with the Zakharov-Shabat equations of the Toda hierarchy. Fourth, singular points are studied from a global viewpoint, using our earlier observation that W-surfaces may be regarded as instantons. The global indices of the W-geometry, which are written in terms of the Toda fields, are shown to be the instanton numbers for associated mappings of W-surfaces into the Grassmannians. The relation with the singularities of W-surface is derived by combining the Toda equations with the Gauss-Bonnet theorem. (orig.)
Quantum experiments without classical counterparts
International Nuclear Information System (INIS)
Pavicic, M.
2005-01-01
Full text: We present a generalized and exhaustive method of finding the directions of the quantization axes of the measured eigenstates within experiments which have no classical counterparts. The method relies on a constructive and exhaustive definition of sets of such directions (which we call Kochen-Specker vectors) in a Hilbert space of any dimension as well as of all the remaining vectors of the space. Kochen-Specker vectors are elements of any set of orthonormal states, i.e., vectors in n-dim Hilbert space, Hn, n > 2 to which it is impossible to assign 1s and 0s in such a way that no two mutually orthogonal vectors from the set are both assigned 1 and that not all mutually orthogonal vectors are assigned 0. Our constructive definition of such Kochen-Specker vectors is based on algorithms that generate MMP diagrams corresponding to blocks of orthogonal vectors in Rn, on algorithms that single out those diagrams on which algebraic to 0-1 states cannot be defined, and on algorithms that solve nonlinear equations describing the orthogonalities of the vectors by means of statistically polynomially complex interval analysis and self-teaching programs. The algorithms are limited neither by the number of dimensions nor by the number of vectors. To demonstrate the power of the algorithms, all 4-dim KS vector systems containing up to 24 vectors were generated and described, all 3-dim vector systems containing up to 30 vectors were scanned, and several general properties of KS vectors were found. (author)
Classical and semiclassical aspects of chemical dynamics
International Nuclear Information System (INIS)
Gray, S.K.
1982-08-01
Tunneling in the unimolecular reactions H 2 C 2 → HC 2 H, HNC → HCN, and H 2 CO → H 2 + CO is studied with a classical Hamiltonian that allows the reaction coordinate and transverse vibrational modes to be considered directly. A combination of classical perturbation theory and the semiclassical WKB method allows tunneling probabilities to be obtained, and a statistical theory (RRKM) is used to construct rate constants for these reactions in the tunneling regime. In this fashion, it is found that tunneling may be important, particularly for low excitation energies. Nonadiabatic charge transfer in the reaction Na + I → Na + + I - is treated with classical trajectories based on a classical Hamiltonian that is the analogue of a quantum matrix representation. The charge transfer cross section obtained is found to agree reasonably well with the exact quantum results. An approximate semiclassical formula, valid at high energies, is also obtained. The interaction of radiation and matter is treated from a classical viewpoint. The excitation of an HF molecule in a strong laser is described with classical trajectories. Quantum mechanical results are also obtained and compared to the classical results. Although the detailed structure of the pulse time averaged energy absorption cannot be reproduced classically, classical mechanics does predict the correct magnitude of energy absorption, as well as certain other qualitative features. The classical behavior of a nonrotating diatomic molecule in a strong laser field is considered further, by generating a period advance map that allows the solution over many periods of oscillation of the laser to be obtained with relative ease. Classical states are found to form beautiful spirals in phase space as time progresses. A simple pendulum model is found to describe the major qualitative features
Classical topology and quantum states
Indian Academy of Sciences (India)
structures) can be reconstructed using Gel'fand–Naimark theory and its ..... pair production and annihilation [23], quantum gravity too can be expected to become ..... showed their utility for research of current interest such as topology change ...
A critical review of classical bouncing cosmologies
Energy Technology Data Exchange (ETDEWEB)
Battefeld, Diana, E-mail: dbattefe@astro.physik.uni-goettingen.de [Institut for Astrophysics, University of Goettingen, Friedrich-Hund Platz 1, D-37077 (Germany); Peter, Patrick, E-mail: peter@iap.fr [Institut d’Astrophysique de Paris, UMR 7095-CNRS, Université Pierre et Marie Curie, 98 bis boulevard Arago, 75014 Paris (France)
2015-04-01
Given the proliferation of bouncing models in recent years, we gather and critically assess these proposals in a comprehensive review. The PLANCK data shows an unmistakably red, quasi scale-invariant, purely adiabatic primordial power spectrum and no primary non-Gaussianities. While these observations are consistent with inflationary predictions, bouncing cosmologies aspire to provide an alternative framework to explain them. Such models face many problems, both of the purely theoretical kind, such as the necessity of violating the NEC and instabilities, and at the cosmological application level, as exemplified by the possible presence of shear. We provide a pedagogical introduction to these problems and also assess the fitness of different proposals with respect to the data. For example, many models predict a slightly blue spectrum and must be fine-tuned to generate a red spectral index; as a side effect, large non-Gaussianities often result. We highlight several promising attempts to violate the NEC without introducing dangerous instabilities at the classical and/or quantum level. If primordial gravitational waves are observed, certain bouncing cosmologies, such as the cyclic scenario, are in trouble, while others remain valid. We conclude that, while most bouncing cosmologies are far from providing an alternative to the inflationary paradigm, a handful of interesting proposals have surfaced, which warrant further research. The constraints and lessons learned as laid out in this review might guide future research.
De Sitter hunting in a classical landscape
International Nuclear Information System (INIS)
Danielsson, U.H.; Van Riet, T.; Haque, S.S.; Koerber, P.; Shiu, G.; Wrase, T.
2011-01-01
We elaborate on the construction of de Sitter solutions from IIA orientifolds of SU(3)-structure manifolds that solve the 10-dimensional equations of motion at tree-level in the approximation of smeared sources. First we classify geometries that are orbifolds of a group manifold covering space which, upon the proper inclusion of O6 planes, can be described within the framework of N = 1 supergravity in 4D. Then we scan systematically for de Sitter solutions, obtained as critical points of an effective 4D potential. Apart from finding many new solutions we emphasize the challenges in constructing explicit classical de Sitter vacua, which have sofar not been met. These challenges are interesting avenues for further research and include finding solutions that are perturbatively stable, satisfy charge and flux quantization, and have genuine localized (versus smeared) orientifold sources. This paper intends to be self-contained and pedagogical, and thus can serve as a guide to the necessary technical tools required for this line of research. In an appendix we explain how to study flux and charge quantization in the presence of a non-trivial H-field using twisted homology. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)
The complexity of classical music networks
Rolla, Vitor; Kestenberg, Juliano; Velho, Luiz
2018-02-01
Previous works suggest that musical networks often present the scale-free and the small-world properties. From a musician's perspective, the most important aspect missing in those studies was harmony. In addition to that, the previous works made use of outdated statistical methods. Traditionally, least-squares linear regression is utilised to fit a power law to a given data set. However, according to Clauset et al. such a traditional method can produce inaccurate estimates for the power law exponent. In this paper, we present an analysis of musical networks which considers the existence of chords (an essential element of harmony). Here we show that only 52.5% of music in our database presents the scale-free property, while 62.5% of those pieces present the small-world property. Previous works argue that music is highly scale-free; consequently, it sounds appealing and coherent. In contrast, our results show that not all pieces of music present the scale-free and the small-world properties. In summary, this research is focused on the relationship between musical notes (Do, Re, Mi, Fa, Sol, La, Si, and their sharps) and accompaniment in classical music compositions. More information about this research project is available at https://eden.dei.uc.pt/~vitorgr/MS.html.
Expert Western Classical Music Improvisers' Strategies
Després, Jean-Philippe; Burnard, Pamela; Dubé, Francis; Stévance, Sophie
2017-01-01
The growing interest in musical improvisation is exemplified by the body of literatures evidencing the positive impacts of improvisation learning on the musical apprentice's aptitudes and the increasing presence of improvisation in Western classical concert halls and competitions. However, high-level Western classical music improvisers' thinking…
Tarnished Gold: Classical Music in America
Asia, Daniel
2010-01-01
A few articles have appeared recently regarding the subject of the health of classical music (or more broadly, the fine arts) in America. These include "Classical Music's New Golden Age," by Heather Mac Donald, in the "City Journal" and "The Decline of the Audience," by Terry Teachout, in "Commentary." These articles appeared around the time of…
The Dirac equation in classical statistical mechanics
International Nuclear Information System (INIS)
Ord, G.N.
2002-01-01
The Dirac equation, usually obtained by 'quantizing' a classical stochastic model is here obtained directly within classical statistical mechanics. The special underlying space-time geometry of the random walk replaces the missing analytic continuation, making the model 'self-quantizing'. This provides a new context for the Dirac equation, distinct from its usual context in relativistic quantum mechanics
Converting Projects from STK Classic to STK
Energy Technology Data Exchange (ETDEWEB)
Foucar, James G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
2014-08-01
The version of STK (Sierra ToolKit) that has long been provided with Trilinos is no longer supported by the core develop- ment team. With the introduction of a the new STK library into Trilinos, the old STK has been renamed to stk classic. This document contains a rough guide of how to port a stk classic code to STK.
Hilbert space theory of classical electrodynamics
Indian Academy of Sciences (India)
Furthermore, following Bondar et al, {\\it Phys. Rev.} A 88, 052108 (2013), it is pointed out that quantum processes that preserve the positivity or nonpositivity of theWigner function can be implemented by classical optics. This may be useful in interpreting quantum information processing in terms of classical optics.
Linguistic Investigations into Ellipsis in Classical Sanskrit
Gillon, Brendan S.
Ellipsis is a common phenomenon of Classical Sanskrit prose. No inventory of the forms of ellipsis in Classical Sanskrit has been made. This paper presents an inventory, based both on a systematic investigation of one text and on examples based on sundry reading.
Quantum Statistical Operator and Classically Chaotic Hamiltonian ...
African Journals Online (AJOL)
Quantum Statistical Operator and Classically Chaotic Hamiltonian System. ... Journal of the Nigerian Association of Mathematical Physics ... In a Hamiltonian system von Neumann Statistical Operator is used to tease out the quantum consequence of (classical) chaos engendered by the nonlinear coupling of system to its ...
Classical and Quantum-Mechanical State Reconstruction
Khanna, F. C.; Mello, P. A.; Revzen, M.
2012-01-01
The aim of this paper is to present the subject of state reconstruction in classical and in quantum physics, a subject that deals with the experimentally acquired information that allows the determination of the physical state of a system. Our first purpose is to explain a method for retrieving a classical state in phase space, similar to that…
Modular sequent calculi for classical modal logics
Gilbert, David; Maffezioli, Paolo
This paper develops sequent calculi for several classical modal logics. Utilizing a polymodal translation of the standard modal language, we are able to establish a base system for the minimal classical modal logic E from which we generate extensions (to include M, C, and N) in a modular manner. Our
Surfactant enhanced non-classical extraction
International Nuclear Information System (INIS)
Szymanowski, J.
2000-01-01
Surfactant enhanced non-classical extractions are presented and discussed. They include micellar enhanced ultrafiltration and cloud point extraction. The ideas of the processes are given and the main features are presented. They are compared to the classical solvent extraction. The fundamental of micellar solutions and their solubilisation abilities are also discussed. (author)
Overgroups of root groups in classical groups
Aschbacher, Michael
2016-01-01
The author extends results of McLaughlin and Kantor on overgroups of long root subgroups and long root elements in finite classical groups. In particular he determines the maximal subgroups of this form. He also determines the maximal overgroups of short root subgroups in finite classical groups and the maximal overgroups in finite orthogonal groups of c-root subgroups.
Mimicking anti-correlations with classical interference
International Nuclear Information System (INIS)
Godoy, S; Seifert, B; Wallentowitz, S
2013-01-01
It is shown how classical laser light impinging on a beam splitter with internal reflections may mimic anti-correlations of the detected outputs, similar to those observed for anti-bunched light. The experimentally observed anti-correlation may be interpreted as a classical Hong–Ou–Mandel dip. (paper)
Surfactant enhanced non-classical extraction
International Nuclear Information System (INIS)
Szymanowski, J.
1999-01-01
Surfactant enhanced non-classical extractions are presented and discussed. They include micellar enhanced ultrafiltration and cloud point extraction. The ideas of the processes are given and the main features are presented. They are compared to the classical solvent extraction. The fundamental of micellar solutions and their solubilization abilities are also discussed. (author)
Quantum Communication Attacks on Classical Cryptographic Protocols
DEFF Research Database (Denmark)
Damgård, Ivan Bjerre
, one can show that the protocol remains secure even under such an attack. However, there are also cases where the honest players are quantum as well, even if the protocol uses classical communication. For instance, this is the case when classical multiparty computation is used as a “subroutine......In the literature on cryptographic protocols, it has been studied several times what happens if a classical protocol is attacked by a quantum adversary. Usually, this is taken to mean that the adversary runs a quantum algorithm, but communicates classically with the honest players. In several cases......” in quantum multiparty computation. Furthermore, in the future, players in a protocol may employ quantum computing simply to improve efficiency of their local computation, even if the communication is supposed to be classical. In such cases, it no longer seems clear that a quantum adversary must be limited...
Classical field approach to quantum weak measurements.
Dressel, Justin; Bliokh, Konstantin Y; Nori, Franco
2014-03-21
By generalizing the quantum weak measurement protocol to the case of quantum fields, we show that weak measurements probe an effective classical background field that describes the average field configuration in the spacetime region between pre- and postselection boundary conditions. The classical field is itself a weak value of the corresponding quantum field operator and satisfies equations of motion that extremize an effective action. Weak measurements perturb this effective action, producing measurable changes to the classical field dynamics. As such, weakly measured effects always correspond to an effective classical field. This general result explains why these effects appear to be robust for pre- and postselected ensembles, and why they can also be measured using classical field techniques that are not weak for individual excitations of the field.
Classical-driving-assisted entanglement dynamics control
Energy Technology Data Exchange (ETDEWEB)
Zhang, Ying-Jie, E-mail: yingjiezhang@qfnu.edu.cn [Shandong Provincial Key Laboratory of Laser Polarization and Information Technology, Department of Physics, Qufu Normal University, Qufu 273165 (China); Han, Wei [Shandong Provincial Key Laboratory of Laser Polarization and Information Technology, Department of Physics, Qufu Normal University, Qufu 273165 (China); Xia, Yun-Jie, E-mail: yjxia@qfnu.edu.cn [Shandong Provincial Key Laboratory of Laser Polarization and Information Technology, Department of Physics, Qufu Normal University, Qufu 273165 (China); Fan, Heng, E-mail: hfan@iphy.ac.cn [Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190 (China); Collaborative Innovation Center of Quantum Matter, Beijing, 100190 (China)
2017-04-15
We propose a scheme of controlling entanglement dynamics of a quantum system by applying the external classical driving field for two atoms separately located in a single-mode photon cavity. It is shown that, with a judicious choice of the classical-driving strength and the atom–photon detuning, the effective atom–photon interaction Hamiltonian can be switched from Jaynes–Cummings model to anti-Jaynes–Cummings model. By tuning the controllable atom–photon interaction induced by the classical field, we illustrate that the evolution trajectory of the Bell-like entanglement states can be manipulated from entanglement-sudden-death to no-entanglement-sudden-death, from no-entanglement-invariant to entanglement-invariant. Furthermore, the robustness of the initial Bell-like entanglement can be improved by the classical driving field in the leaky cavities. This classical-driving-assisted architecture can be easily extensible to multi-atom quantum system for scalability.
Interaction between classical and quantum systems
International Nuclear Information System (INIS)
Sherry, T.N.; Sudarshan, E.C.G.
1977-10-01
An unconventional approach to the measurement problem in quantum mechanics is considered--the apparatus is treated as a classical system, belonging to the macro-world. In order to have a measurement the apparatus must interact with the quantum system. As a first step, the classical apparatus is embedded into a large quantum mechanical structure, making use of a superselection principle. The apparatus and system are coupled such that the apparatus remains classical (principle of integrity), and unambiguous information of the values of a quantum observable are transferred to the variables of the apparatus. Further measurement of the classical apparatus can be done, causing no problems of principle. Thus interactions causing pointers to move (which are not treated) can be added. The restrictions placed by the principle of integrity on the form of the interaction between classical and quantum systems are examined and illustration is given by means of a simple example in which one sees the principle of integrity at work
Citation Classics from Industrial Marketing Management
DEFF Research Database (Denmark)
Lindgreen, Adam; Di Benedetto, C. Anthony
2017-01-01
, system sellers and systems integrator, third-party logistics providers, and value). Finally, each of the 30 citation classics is introduced, and the classics' theoretical implications to business-to-business marketing management and fields related to (e.g., supply chain management, strategic management......This article proposes a categorization of what constitutes a citation classic. General observations reveal, with regard to the top 30 citation classics from Industrial Marketing Management, the number of authors per article, country of origin of the lead author, and type of article (literature...... review, qualitative methodology, or quantitative methodology). In addition, these citation classics can be classified by topic (firm performance, goods-dominant and service-dominant logics, Internet and high-technology markets, product innovation, relationships and business networks, supply chains...
Quantum Communication Attacks on Classical Cryptographic Protocols
DEFF Research Database (Denmark)
Damgård, Ivan Bjerre
, one can show that the protocol remains secure even under such an attack. However, there are also cases where the honest players are quantum as well, even if the protocol uses classical communication. For instance, this is the case when classical multiparty computation is used as a “subroutine......” in quantum multiparty computation. Furthermore, in the future, players in a protocol may employ quantum computing simply to improve efficiency of their local computation, even if the communication is supposed to be classical. In such cases, it no longer seems clear that a quantum adversary must be limited......In the literature on cryptographic protocols, it has been studied several times what happens if a classical protocol is attacked by a quantum adversary. Usually, this is taken to mean that the adversary runs a quantum algorithm, but communicates classically with the honest players. In several cases...
Representational Realism, Closed Theories and the Quantum to Classical Limit
de Ronde, Christian
In this chapter, we discuss the representational realist stance as a pluralistontic approach to inter-theoretic relationships. Our stance stresses the fact that physical theories require the necessary consideration of a conceptual level of discourse which determines and configures the specific field of phenomena discussed by each particular theory. We will criticize the orthodox line of research which has grounded the analysis about QM in two (Bohrian) metaphysical presuppositions - accepted in the present as dogmas that all interpretations must follow. We will also examine how the orthodox project of "bridging the gap" between the quantum and the classical domains has constrained the possibilities of research, producing only a limited set of interpretational problems which only focus in the justification of "classical reality" and exclude the possibility of analyzing the possibilities of non-classical conceptual representations of QM. The representational realist stance introduces two new problems, namely, the superposition problem and the contextuality problem, which consider explicitly the conceptual representation of orthodox QM beyond the mere reference to mathematical structures and measurement outcomes. In the final part of the chapter, we revisit, from representational realist perspective, the quantum to classical limit and the orthodox claim that this inter-theoretic relation can be explained through the principle of decoherence.
Driven topological systems in the classical limit
Duncan, Callum W.; Öhberg, Patrik; Valiente, Manuel
2017-03-01
Periodically driven quantum systems can exhibit topologically nontrivial behavior, even when their quasienergy bands have zero Chern numbers. Much work has been conducted on noninteracting quantum-mechanical models where this kind of behavior is present. However, the inclusion of interactions in out-of-equilibrium quantum systems can prove to be quite challenging. On the other hand, the classical counterpart of hard-core interactions can be simulated efficiently via constrained random walks. The noninteracting model, proposed by Rudner et al. [Phys. Rev. X 3, 031005 (2013), 10.1103/PhysRevX.3.031005], has a special point for which the system is equivalent to a classical random walk. We consider the classical counterpart of this model, which is exact at a special point even when hard-core interactions are present, and show how these quantitatively affect the edge currents in a strip geometry. We find that the interacting classical system is well described by a mean-field theory. Using this we simulate the dynamics of the classical system, which show that the interactions play the role of Markovian, or time-dependent disorder. By comparing the evolution of classical and quantum edge currents in small lattices, we find regimes where the classical limit considered gives good insight into the quantum problem.
Emergence of quantum mechanics from classical statistics
International Nuclear Information System (INIS)
Wetterich, C
2009-01-01
The conceptual setting of quantum mechanics is subject to an ongoing debate from its beginnings until now. The consequences of the apparent differences between quantum statistics and classical statistics range from the philosophical interpretations to practical issues as quantum computing. In this note we demonstrate how quantum mechanics can emerge from classical statistical systems. We discuss conditions and circumstances for this to happen. Quantum systems describe isolated subsystems of classical statistical systems with infinitely many states. While infinitely many classical observables 'measure' properties of the subsystem and its environment, the state of the subsystem can be characterized by the expectation values of only a few probabilistic observables. They define a density matrix, and all the usual laws of quantum mechanics follow. No concepts beyond classical statistics are needed for quantum physics - the differences are only apparent and result from the particularities of those classical statistical systems which admit a quantum mechanical description. In particular, we show how the non-commuting properties of quantum operators are associated to the use of conditional probabilities within the classical system, and how a unitary time evolution reflects the isolation of the subsystem.
Classical and anaplastic seminoma: Difference in survival
International Nuclear Information System (INIS)
Bobba, V.S.; Mittal, B.B.; Hoover, S.V.; Kepka, A.
1987-01-01
The authors undertook a retrospective study of seminoma patients treated with radiation therapy between 1961 and 1985. The classical group consisted of 66 patients, of whom 47 were stage I and 19 were stage II. The anaplastic group consisted of 21 patients, of whom 11 were stage I, nine were stage II, and one was stage III. The median follow-up was 66 months. The five-year crude survival rate for the entire group was 92%, for classical 96%, and for anaplastic 78% (P<.005). Similarly, there was a significant difference (P<.005) in actuarial relapse-free survival at 5 years between classical and anaplastic seminoma. For classical stage I, the relapse-free actuarial 5-year survival rate was 96; for classical stage II, 84%. For anaplastic stage I the relapse-free actuarial 5-year survival rate was 82%, and for stage II 75%. Six patients in the classical group (9%) failed treatment. In the anaplastic group, five patients or 24 failed treatment. Therefore, the authors' data suggest a difference in survival and failure rate between classical and anaplastic seminoma. Extratesticular seminoma with anaplastic histology has an even worse prognosis
Fluctuations of wavefunctions about their classical average
International Nuclear Information System (INIS)
Benet, L; Flores, J; Hernandez-Saldana, H; Izrailev, F M; Leyvraz, F; Seligman, T H
2003-01-01
Quantum-classical correspondence for the average shape of eigenfunctions and the local spectral density of states are well-known facts. In this paper, the fluctuations of the quantum wavefunctions around the classical value are discussed. A simple random matrix model leads to a Gaussian distribution of the amplitudes whose width is determined by the classical shape of the eigenfunction. To compare this prediction with numerical calculations in chaotic models of coupled quartic oscillators, we develop a rescaling method for the components. The expectations are broadly confirmed, but deviations due to scars are observed. This effect is much reduced when both Hamiltonians have chaotic dynamics
A Classical Introduction to Galois Theory
Newman, Stephen C
2012-01-01
This book provides an introduction to Galois theory and focuses on one central theme - the solvability of polynomials by radicals. Both classical and modern approaches to the subject are described in turn in order to have the former (which is relatively concrete and computational) provide motivation for the latter (which can be quite abstract). The theme of the book is historically the reason that Galois theory was created, and it continues to provide a platform for exploring both classical and modern concepts. This book examines a number of problems arising in the area of classical mathematic
Classical realizability in the CPS target language
DEFF Research Database (Denmark)
Frey, Jonas
2016-01-01
Motivated by considerations about Krivine's classical realizability, we introduce a term calculus for an intuitionistic logic with record types, which we call the CPS target language. We give a reformulation of the constructions of classical realizability in this language, using the categorical...... techniques of realizability triposes and toposes. We argue that the presentation of classical realizability in the CPS target language simplifies calculations in realizability toposes, in particular it admits a nice presentation of conjunction as intersection type which is inspired by Girard's ludics....
Classical dynamics of particles and systems
Marion, Jerry B
1965-01-01
Classical Dynamics of Particles and Systems presents a modern and reasonably complete account of the classical mechanics of particles, systems of particles, and rigid bodies for physics students at the advanced undergraduate level. The book aims to present a modern treatment of classical mechanical systems in such a way that the transition to the quantum theory of physics can be made with the least possible difficulty; to acquaint the student with new mathematical techniques and provide sufficient practice in solving problems; and to impart to the student some degree of sophistication in handl
Directory of Open Access Journals (Sweden)
Inggit Sitowati
2014-06-01
Full Text Available Karta Pustaka is one of the cultural institutions in Yogyakarta, which has a classical music concert program. The purpose of this study is to describe the history of Karta Pustaka and organizing classical music concerts, the concert format, and its role in supporting classical music education in Yogyakarta. The method used in this study is qualitative research with historical and musicological approach.The data are collected by using interviews, documents and observations. Data were analyzed using qualitative descriptions technicians. The results showed that Karta Pustaka as cultural institution has become a classical musicmedia which has a supporting role in classical music education in Yogyakarta. The classical music concert program and classical music workshop held by Karta Pustaka information and knowledge for the students and people of musical art in Yogyakarta. In addition Karta Pustaka also acts as a forming media and the development of consumer’s classical music tastes and styles in Yogyakarta.
African Journals Online (AJOL)
ebutamanya
2015-03-02
Mar 2, 2015 ... Joseph Daniels1,&, Ruth Nduati1,2, James Kiarie1,3, Carey Farquhar1,4,5 .... or basic science research career (Socio-Behavioral Research, .... a research environment that supports knowledge sharing to develop research ...
Socio-economic institutions in classical political economy of Ukraine
Directory of Open Access Journals (Sweden)
Yu.V. Ushchapovskyy
2015-09-01
Full Text Available Fragmentary researches of socio-economic institutions by classical political economy are caused by the absence of social components in its methodological «core». The article concentrates on the ideas of institutionalism in the context of classical political economy formation. The author underlines the necessity to adapt the analysis of socio-economic institutions in the heritage of classical political economy in Ukraine of the 19-th century to the creation of an integral conception of genesis and evolution of institutionalism in Ukrainian economic thought. Following the traditions of European economic science, Ukrainian scientists tried to take into account social contradictions, the needs in democratic transformations of social relations in their works. In spite of absence of the category of «standard (rule» among Adam Smith’s followers, and Ukrainian economists paid attention to a social problematic in the context of traditional researches of classical political economy, there is the necessity to examine socio-economic institutions in their heritage and the possibility of its application to the formation of the paradigm of modern institutionalism. Michail Baludyanskiy considered that a state could limit the freedom of an economic activity only on the base of generally accepted standards, but in this case contributing to safety and freedom of an economic activity. National system of economy, its legislative and management systems must conceptually obey economic policy, Anthropocentrism defined the philosophical conception of Tihon Stepanov’s political economy. He followed methodological holism as he concluded the characteristics of an individual on the base of characteristics of institutions (society. Ivan Vernadskiy’s researches concerning behavior of an individual and his trials to characterize value from a consumer’s point of view don’t fully correspond to traditional classical political economy. To improve Adam Smith’s study
Bohmian measures and their classical limit
Markowich, Peter; Paul, Thierry; Sparber, Christof
2010-01-01
We consider a class of phase space measures, which naturally arise in the Bohmian interpretation of quantum mechanics. We study the classical limit of these so-called Bohmian measures, in dependence on the scale of oscillations and concentrations
Quantum manifestations of classical resonance zones
International Nuclear Information System (INIS)
De Leon, N.; Davis, M.J.; Heller, E.J.
1984-01-01
We examine the concept of nodal breakup of wave functions as a criterion for quantum mechanical ergodicity. We find that complex nodal structure of wave functions is not sufficient to determine quantum mechanical ergodicity. The influence of classical resonances [which manifest themselves as classical resonance zones (CRZ)] may also be responsible for the seeming complexity of nodal structure. We quantify this by reexamining one of the two systems studied by Stratt, Handy, and Miller [J. Chem. Phys. 71, 3311 (1974)] from both a quantum mechanical and classical point of view. We conclude that quasiperiodic classical motion can account for highly distorted quantum eigenstates. One should always keep this in mind when addressing questions regarding quantum mechanical ergodicity
Classical geometry from the quantum Liouville theory
Hadasz, Leszek; Jaskólski, Zbigniew; Piaţek, Marcin
2005-09-01
Zamolodchikov's recursion relations are used to analyze the existence and approximations to the classical conformal block in the case of four parabolic weights. Strong numerical evidence is found that the saddle point momenta arising in the classical limit of the DOZZ quantum Liouville theory are simply related to the geodesic length functions of the hyperbolic geometry on the 4-punctured Riemann sphere. Such relation provides new powerful methods for both numerical and analytical calculations of these functions. The consistency conditions for the factorization of the 4-point classical Liouville action in different channels are numerically verified. The factorization yields efficient numerical methods to calculate the 4-point classical action and, by the Polyakov conjecture, the accessory parameters of the Fuchsian uniformization of the 4-punctured sphere.
Classical geometry from the quantum Liouville theory
Energy Technology Data Exchange (ETDEWEB)
Hadasz, Leszek [M. Smoluchowski Institute of Physics, Jagellonian University, Reymonta 4, 30-059 Cracow (Poland)]. E-mail: hadasz@th.if.uj.edu.pl; Jaskolski, Zbigniew [Institute of Theoretical Physics, University of WrocIaw, pl. M. Borna, 950-204 WrocIaw (Poland)]. E-mail: jask@ift.uni.wroc.pl; Piatek, Marcin [Institute of Theoretical Physics, University of WrocIaw, pl. M. Borna, 950-204 WrocIaw (Poland)]. E-mail: piatek@ift.uni.wroc.pl
2005-09-26
Zamolodchikov's recursion relations are used to analyze the existence and approximations to the classical conformal block in the case of four parabolic weights. Strong numerical evidence is found that the saddle point momenta arising in the classical limit of the DOZZ quantum Liouville theory are simply related to the geodesic length functions of the hyperbolic geometry on the 4-punctured Riemann sphere. Such relation provides new powerful methods for both numerical and analytical calculations of these functions. The consistency conditions for the factorization of the 4-point classical Liouville action in different channels are numerically verified. The factorization yields efficient numerical methods to calculate the 4-point classical action and, by the Polyakov conjecture, the accessory parameters of the Fuchsian uniformization of the 4-punctured sphere.
Classical geometry from the quantum Liouville theory
International Nuclear Information System (INIS)
Hadasz, Leszek; Jaskolski, Zbigniew; Piatek, Marcin
2005-01-01
Zamolodchikov's recursion relations are used to analyze the existence and approximations to the classical conformal block in the case of four parabolic weights. Strong numerical evidence is found that the saddle point momenta arising in the classical limit of the DOZZ quantum Liouville theory are simply related to the geodesic length functions of the hyperbolic geometry on the 4-punctured Riemann sphere. Such relation provides new powerful methods for both numerical and analytical calculations of these functions. The consistency conditions for the factorization of the 4-point classical Liouville action in different channels are numerically verified. The factorization yields efficient numerical methods to calculate the 4-point classical action and, by the Polyakov conjecture, the accessory parameters of the Fuchsian uniformization of the 4-punctured sphere
Stabilization of classic and quantum systems
International Nuclear Information System (INIS)
Buts, V.A.
2012-01-01
It is shown that the mechanism of quantum whirligig can be successfully used for stabilization of classical systems. In particular, the conditions for stabilization of charged particles and radiation fluxes in plasma are found.
Classical limit for semirelativistic Hartree systems
Aki, Gonca L.; Markowich, Peter A.; Sparber, Christof
2008-01-01
Wigner transformation techniques that its classical limit yields the well known relativistic Vlasov-Poisson system. The result holds for the case of attractive and repulsive mean-field interactions, with an additional size constraint in the attractive
Classical algebra its nature, origins, and uses
Cooke, Roger L
2008-01-01
This insightful book combines the history, pedagogy, and popularization of algebra to present a unified discussion of the subject. Classical Algebra provides a complete and contemporary perspective on classical polynomial algebra through the exploration of how it was developed and how it exists today. With a focus on prominent areas such as the numerical solutions of equations, the systematic study of equations, and Galois theory, this book facilitates a thorough understanding of algebra and illustrates how the concepts of modern algebra originally developed from classical algebraic precursors. This book successfully ties together the disconnect between classical and modern algebraand provides readers with answers to many fascinating questions that typically go unexamined, including: What is algebra about? How did it arise? What uses does it have? How did it develop? What problems and issues have occurred in its history? How were these problems and issues resolved? The author answers these questions and more,...
Persistent entanglement in the classical limit
Energy Technology Data Exchange (ETDEWEB)
Everitt, M J [Centre for Physical Electronics and Quantum Technology, School of Science and Technology, University of Sussex, Falmer, Brighton BN1 9QT (United Kingdom); Clark, T D [Centre for Physical Electronics and Quantum Technology, School of Science and Technology, University of Sussex, Falmer, Brighton BN1 9QT (United Kingdom); Stiffell, P B [Centre for Physical Electronics and Quantum Technology, School of Science and Technology, University of Sussex, Falmer, Brighton BN1 9QT (United Kingdom); Ralph, J F [Department of Electrical and Electronic Engineering, Liverpool University, Brownlow Hill, Liverpool L69 3GJ (United Kingdom); Bulsara, A R [Space and Naval Warfare Systems Center, Code 2363, 53560 Hull Street, San Diego, CA 92152-5001 (United States); Harland, C J [Centre for Physical Electronics and Quantum Technology, School of Science and Technology, University of Sussex, Falmer, Brighton BN1 9QT (United Kingdom)
2005-02-01
The apparent difficulty in recovering classical nonlinear dynamics and chaos from standard quantum mechanics has been the subject of a great deal of interest over the last 20 years. For open quantum systems-those coupled to a dissipative environment and/or a measurement device-it has been demonstrated that chaotic-like behaviour can be recovered in the appropriate classical limit. In this paper, we investigate the entanglement generated between two nonlinear oscillators, coupled to each other and to their environment. Entanglement-the inability to factorize coupled quantum systems into their constituent parts-is one of the defining features of quantum mechanics. Indeed, it underpins many of the recent developments in quantum technologies. Here, we show that the entanglement characteristics of two 'classical' states (chaotic and periodic solutions) differ significantly in the classical limit. In particular, we show that significant levels of entanglement are preserved only in the chaotic-like solutions.
Classic Phenylketonuria: Diagnosis Through Heterozygote Detection
Griffin, Robert F.; Elsas, Louis J.
1975-01-01
In an attempt to improve the identification of the asymptomatic carrier of classic phenylketonuria (PKU) 59 male and female normal control Ss were differentiated from 18 males and females heterozgous for PKU. (DB)
Minimal classical communication and measurement complexity for ...
Indian Academy of Sciences (India)
Minimal classical communication and measurement complexity for quantum ... Entanglement; teleportation; secret sharing; information splitting. ... Ahmedabad 380 009, India; Birla Institute of Technology and Science, Pilani 333 031, India ...
The classical limit of W-algebras
International Nuclear Information System (INIS)
Figueroa-O'Farrill, J.M.; Ramos, E.
1992-01-01
We define and compute explicitly the classical limit of the realizations of W n appearing as hamiltonian structures of generalized KdV hierarchies. The classical limit is obtained by taking the commutative limit of the ring of pseudodifferential operators. These algebras - denoted w n - have free field realizations in which the generators are given by the elementary symmetric polynomials in the free fields. We compute the algebras explicitly and we show that they are all reductions of a new algebra w KP , which is proposed as the universal classical W-algebra for the w n series. As a deformation of this algebra we also obtain w 1+∞ , the classical limit of W 1+∞ . (orig.)
Quantum vertex model for reversible classical computing.
Chamon, C; Mucciolo, E R; Ruckenstein, A E; Yang, Z-C
2017-05-12
Mappings of classical computation onto statistical mechanics models have led to remarkable successes in addressing some complex computational problems. However, such mappings display thermodynamic phase transitions that may prevent reaching solution even for easy problems known to be solvable in polynomial time. Here we map universal reversible classical computations onto a planar vertex model that exhibits no bulk classical thermodynamic phase transition, independent of the computational circuit. Within our approach the solution of the computation is encoded in the ground state of the vertex model and its complexity is reflected in the dynamics of the relaxation of the system to its ground state. We use thermal annealing with and without 'learning' to explore typical computational problems. We also construct a mapping of the vertex model into the Chimera architecture of the D-Wave machine, initiating an approach to reversible classical computation based on state-of-the-art implementations of quantum annealing.
Can classical noise enhance quantum transmission?
International Nuclear Information System (INIS)
Wilde, Mark M
2009-01-01
A modified quantum teleportation protocol broadens the scope of the classical forbidden-interval theorems for stochastic resonance. The fidelity measures performance of quantum communication. The sender encodes the two classical bits for quantum teleportation as weak bipolar subthreshold signals and sends them over a noisy classical channel. Two forbidden-interval theorems provide a necessary and sufficient condition for the occurrence of the nonmonotone stochastic resonance effect in the fidelity of quantum teleportation. The condition is that the noise mean must fall outside a forbidden interval related to the detection threshold and signal value. An optimal amount of classical noise benefits quantum communication when the sender transmits weak signals, the receiver detects with a high threshold and the noise mean lies outside the forbidden interval. Theorems and simulations demonstrate that both finite-variance and infinite-variance noise benefit the fidelity of quantum teleportation.
Pulse radiolysis - new approaches to the classical technique
Energy Technology Data Exchange (ETDEWEB)
Zagorski, Z P [Institute of Nuclear Research, Warsaw (Poland)
1973-01-01
The present status of classical pulse radiolysis is described as well as trends in the further development of this technique (the investigation of radiolysis with nano- and picoseconds time resolution, new optica and electrochemical methods of intermediate species detection). The attention is concentrated on experimental difficulties of particular versions and the achievements are reviewed critically. This paper is the background for experiments being performed in the Institute of Nuclear Research on new techniques of pulse radiolysis.
Classical Music Clustering Based on Acoustic Features
Wang, Xindi; Haque, Syed Arefinul
2017-01-01
In this paper we cluster 330 classical music pieces collected from MusicNet database based on their musical note sequence. We use shingling and chord trajectory matrices to create signature for each music piece and performed spectral clustering to find the clusters. Based on different resolution, the output clusters distinctively indicate composition from different classical music era and different composing style of the musicians.
Factorizations of one-dimensional classical systems
International Nuclear Information System (INIS)
Kuru, Senguel; Negro, Javier
2008-01-01
A class of one-dimensional classical systems is characterized from an algebraic point of view. The Hamiltonians of these systems are factorized in terms of two functions that together with the Hamiltonian itself close a Poisson algebra. These two functions lead directly to two time-dependent integrals of motion from which the phase motions are derived algebraically. The systems so obtained constitute the classical analogues of the well known factorizable one-dimensional quantum mechanical systems
On the Predictability of Classical Propositional Logic
Finger, Marcelo; Reis, Poliana
2013-01-01
In this work we provide a statistical form of empirical analysis of classical propositional logic decision methods called SAT solvers. This work is perceived as an empirical counterpart of a theoretical movement, called the enduring scandal of deduction, that opposes considering Boolean Logic as trivial in any sense. For that, we study the predictability of classical logic, which we take to be the distribution of the runtime of its decision process. We present a series of experiments that det...
The classical notion of competition revisited
Salvadori, Neri; Signorino, Rodolfo
2010-01-01
The paper seeks to fill a lacuna within Classical economics concerning the process of market price determination in a short-period equilibrium. To this aim, first we distinguish the Classical notion of free competition from the Walrasian notion of perfect competition and we argue that the latter is beset by some theoretical difficulties alien to the former. Second, we reconstruct in some detail Smith and Marx’s views concerning market price determination and we show that Marx’s extensive use ...
Classical geometry Euclidean, transformational, inversive, and projective
Leonard, I E; Liu, A C F; Tokarsky, G W
2014-01-01
Features the classical themes of geometry with plentiful applications in mathematics, education, engineering, and science Accessible and reader-friendly, Classical Geometry: Euclidean, Transformational, Inversive, and Projective introduces readers to a valuable discipline that is crucial to understanding bothspatial relationships and logical reasoning. Focusing on the development of geometric intuitionwhile avoiding the axiomatic method, a problem solving approach is encouraged throughout. The book is strategically divided into three sections: Part One focuses on Euclidean geometry, which p
New mechanism for bubble nucleation: Classical transitions
International Nuclear Information System (INIS)
Easther, Richard; Giblin, John T. Jr; Hui Lam; Lim, Eugene A.
2009-01-01
Given a scalar field with metastable minima, bubbles nucleate quantum mechanically. When bubbles collide, energy stored in the bubble walls is converted into kinetic energy of the field. This kinetic energy can facilitate the classical nucleation of new bubbles in minima that lie below those of the 'parent' bubbles. This process is efficient and classical, and changes the dynamics and statistics of bubble formation in models with multiple vacua, relative to that derived from quantum tunneling.
Classical theory of electric and magnetic fields
Good, Roland H
1971-01-01
Classical Theory of Electric and Magnetic Fields is a textbook on the principles of electricity and magnetism. This book discusses mathematical techniques, calculations, with examples of physical reasoning, that are generally applied in theoretical physics. This text reviews the classical theory of electric and magnetic fields, Maxwell's Equations, Lorentz Force, and Faraday's Law of Induction. The book also focuses on electrostatics and the general methods for solving electrostatic problems concerning images, inversion, complex variable, or separation of variables. The text also explains ma
Classical and Quantum Chaos in Atom Optics
Saif, Farhan
2006-01-01
The interaction of an atom with an electromagnetic field is discussed in the presence of a time periodic external modulating force. It is explained that a control on atom by electromagnetic fields helps to design the quantum analog of classical optical systems. In these atom optical systems chaos may appear at the onset of external fields. The classical and quantum chaotic dynamics is discussed, in particular in an atom optics Fermi accelerator. It is found that the quantum dynamics exhibits ...
ENVIRONMENTALISM AND CLASSIC PARADIGMS OF INTERNATIONAL RELATIONS
D. D. Miniaeva
2014-01-01
This article examines an environmentalism integration process into Three classical paradigms of international relations theory (Liberalism, Realism and Marxism) into Three classical paradigms of international relations theory (Liberalism, Realism and Marxism). The main purpose of this study is to reveal the result of this integration. Methods used in this article include analysis and comparison of "ecological" paradigms on selected parameters (the nature of international relations, actors, ta...
On obtaining classical mechanics from quantum mechanics
International Nuclear Information System (INIS)
Date, Ghanashyam
2007-01-01
Constructing a classical mechanical system associated with a given quantum-mechanical one entails construction of a classical phase space and a corresponding Hamiltonian function from the available quantum structures and a notion of coarser observations. The Hilbert space of any quantum-mechanical system naturally has the structure of an infinite-dimensional symplectic manifold ('quantum phase space'). There is also a systematic, quotienting procedure which imparts a bundle structure to the quantum phase space and extracts a classical phase space as the base space. This works straightforwardly when the Hilbert space carries weakly continuous representation of the Heisenberg group and one recovers the linear classical phase space R 2N . We report on how the procedure also allows extraction of nonlinear classical phase spaces and illustrate it for Hilbert spaces being finite dimensional (spin-j systems), infinite dimensional but separable (particle on a circle) and infinite dimensional but non-separable (polymer quantization). To construct a corresponding classical dynamics, one needs to choose a suitable section and identify an effective Hamiltonian. The effective dynamics mirrors the quantum dynamics provided the section satisfies conditions of semiclassicality and tangentiality
Bohmian mechanics and the emergence of classicality
International Nuclear Information System (INIS)
Matzkin, A
2009-01-01
Bohmian mechanics is endowed with an ontological package that supposedly allows to solve the main interpretational problems of quantum mechanics. We are concerned in this work by the emergence of classicality from the quantum mechanical substrate. We will argue that although being superficially attractive, the de Broglie-Bohm interpretation does not shed new light on the quantum-to-classical transition. This is due to nature of the dynamical law of Bohmian mechanics by which the particles follow the streamlines of the probability flow. As a consequence, Bohmian trajectories can be highly non-classical even when the wavefunction propagates along classical trajectories, as happens in semiclassical systems. In order to account for classical dynamics, Bohmian mechanics needs non-spreading and non-interfering wave packets: this is achieved for practical purposes by having recourse to decoherence and dense measurements. However one then faces the usual fundamental problems associated with the meaning of reduced density matrices. Moreover the specific assets of the de Broglie-Bohm interpretation - in particular the existence of point-like particles pursuing well-defined trajectories - would play no role in accounting for the emergence of classical dynamics.
African Journals Online (AJOL)
A descriptive qualitative research design was used to determine whether participants ... simulation as a teaching method; a manikin offering effective learning; confidence ..... Tesch R. Qualitative Research: Analysis Types and Software Tools.
African Journals Online (AJOL)
research process, as part of which students must find and appraise evidence from research.[5] This highlights that teaching research methodology is inclined towards equipping students ... Students believed that evidence-based practice was vital, yet their understanding of the concept was restricted when compared with the.
Comparison of Classical Test Theory and Item Response Theory in Individual Change Assessment
Jabrayilov, Ruslan; Emons, Wilco H. M.; Sijtsma, Klaas
2016-01-01
Clinical psychologists are advised to assess clinical and statistical significance when assessing change in individual patients. Individual change assessment can be conducted using either the methodologies of classical test theory (CTT) or item response theory (IRT). Researchers have been optimistic
Karlimah
2018-01-01
Many studies suggest that classical music can inccrease the listeners’ intelligence, including mathematical intelligence [3, 12, 2, 11]. In this research, we used the classical music of Baroque era as the backsound during math learning. The research method used was quasi experiment with nonequivalent pretest-posttest control group design to grade V SD students in Tasikmalaya city. The results show that the use of classical music of Baroque era during the learning of mathematics gave a high co...
Emergence of classical theories from quantum mechanics
International Nuclear Information System (INIS)
Hájícek, P
2012-01-01
Three problems stand in the way of deriving classical theories from quantum mechanics: those of realist interpretation, of classical properties and of quantum measurement. Recently, we have identified some tacit assumptions that lie at the roots of these problems. Thus, a realist interpretation is hindered by the assumption that the only properties of quantum systems are values of observables. If one simply postulates the properties to be objective that are uniquely defined by preparation then all difficulties disappear. As for classical properties, the wrong assumption is that there are arbitrarily sharp classical trajectories. It turns out that fuzzy classical trajectories can be obtained from quantum mechanics by taking the limit of high entropy. Finally, standard quantum mechanics implies that any registration on a quantum system is disturbed by all quantum systems of the same kind existing somewhere in the universe. If one works out systematically how quantum mechanics must be corrected so that there is no such disturbance, one finds a new interpretation of von Neumann's 'first kind of dynamics', and so a new way to a solution of the quantum measurement problem. The present paper gives a very short review of this work.
Population structure of the Classic period Maya.
Scherer, Andrew K
2007-03-01
This study examines the population structure of Classic period (A.D. 250-900) Maya populations through analysis of odontometric variation of 827 skeletons from 12 archaeological sites in Mexico, Guatemala, Belize, and Honduras. The hypothesis that isolation by distance characterized Classic period Maya population structure is tested using Relethford and Blangero's (Hum Biol 62 (1990) 5-25) approach to R matrix analysis for quantitative traits. These results provide important biological data for understanding ancient Maya population history, particularly the effects of the competing Tikal and Calakmul hegemonies on patterns of lowland Maya site interaction. An overall F(ST) of 0.018 is found for the Maya area, indicating little among-group variation for the Classic Maya sites tested. Principal coordinates plots derived from the R matrix analysis show little regional patterning in the data, though the geographic outliers of Kaminaljuyu and a pooled Pacific Coast sample did not cluster with the lowland Maya sites. Mantel tests comparing the biological distance matrix to a geographic distance matrix found no association between genetic and geographic distance. In the Relethford-Blangero analysis, most sites possess negative or near-zero residuals, indicating minimal extraregional gene flow. The exceptions were Barton Ramie, Kaminaljuyu, and Seibal. A scaled R matrix analysis clarifies that genetic drift is a consideration for understanding Classic Maya population structure. All results indicate that isolation by distance does not describe Classic period Maya population structure. (c) 2006 Wiley-Liss, Inc.
Lagrangian formulation of classical BMT-theory
International Nuclear Information System (INIS)
Pupasov-Maksimov, Andrey; Deriglazov, Alexei; Guzman, Walberto
2013-01-01
Full text: The most popular classical theory of electron has been formulated by Bargmann, Michel and Telegdi (BMT) in 1959. The BMT equations give classical relativistic description of a charged particle with spin and anomalous magnetic momentum moving in homogeneous electro-magnetic field. This allows to study spin dynamics of polarized beams in uniform fields. In particular, first experimental measurements of muon anomalous magnetic momentum were done using changing of helicity predicted by BMT equations. Surprisingly enough, a systematic formulation and the analysis of the BMT theory are absent in literature. In the present work we particularly fill this gap by deducing Lagrangian formulation (variational problem) for BMT equations. Various equivalent forms of Lagrangian will be discussed in details. An advantage of the obtained classical model is that the Lagrangian action describes a relativistic spinning particle without Grassmann variables, for both free and interacting cases. This implies also the possibility of canonical quantization. In the interacting case, an arbitrary electromagnetic background may be considered, which generalizes the BMT theory formulated to the case of homogeneous fields. The classical model has two local symmetries, which gives an interesting example of constrained classical dynamics. It is surprising, that the case of vanishing anomalous part of the magnetic momentum is naturally highlighted in our construction. (author)
A Case of Classic Raymond Syndrome
Directory of Open Access Journals (Sweden)
Nicholas George Zaorsky
2012-01-01
Full Text Available Classic Raymond syndrome consists of ipsilateral abducens impairment, contralateral central facial paresis, and contralateral hemiparesis. However, subsequent clinical observations argued on the presentation of facial involvement. To validate this entity, we present a case of classic Raymond syndrome with contralateral facial paresis. A 50 year-old man experienced acute onset of horizontal diplopia, left mouth drooling and left-sided weakness. Neurological examination showed he had right abducens nerve palsy, left-sided paresis of the lower part of the face and limbs, and left hyperreflexia. A brain MRI showed a subacute infarct in the right mid-pons. The findings were consistent with those of classic Raymond syndrome. To date, only a few cases of Raymond syndrome, commonly without facial involvement, have been reported. Our case is a validation of classic Raymond syndrome with contralateral facial paresis. We propose the concept of two types of Raymond syndrome: (1 the classic type, which may be produced by a lesion in the mid-pons involving the ipsilateral abducens fascicle and undecussated corticofacial and corticospinal fibers; and (2 the common type, which may be produced by a lesion involving the ipsilateral abducens fascicle and undecussated corticospinal fibers but sparing the corticofacial fibers.
Mathematica for Theoretical Physics Classical Mechanics and Nonlinear Dynamics
Baumann, Gerd
2005-01-01
Mathematica for Theoretical Physics: Classical Mechanics and Nonlinear Dynamics This second edition of Baumann's Mathematica® in Theoretical Physics shows readers how to solve physical problems and deal with their underlying theoretical concepts while using Mathematica® to derive numeric and symbolic solutions. Each example and calculation can be evaluated by the reader, and the reader can change the example calculations and adopt the given code to related or similar problems. The second edition has been completely revised and expanded into two volumes: The first volume covers classical mechanics and nonlinear dynamics. Both topics are the basis of a regular mechanics course. The second volume covers electrodynamics, quantum mechanics, relativity, and fractals and fractional calculus. New examples have been added and the representation has been reworked to provide a more interactive problem-solving presentation. This book can be used as a textbook or as a reference work, by students and researchers alike. A...
Classical and spatial stochastic processes with applications to biology
Schinazi, Rinaldo B
2014-01-01
The revised and expanded edition of this textbook presents the concepts and applications of random processes with the same illuminating simplicity as its first edition, but with the notable addition of substantial modern material on biological modeling. While still treating many important problems in fields such as engineering and mathematical physics, the book also focuses on the highly relevant topics of cancerous mutations, influenza evolution, drug resistance, and immune response. The models used elegantly apply various classical stochastic models presented earlier in the text, and exercises are included throughout to reinforce essential concepts. The second edition of Classical and Spatial Stochastic Processes is suitable as a textbook for courses in stochastic processes at the advanced-undergraduate and graduate levels, or as a self-study resource for researchers and practitioners in mathematics, engineering, physics, and mathematical biology. Reviews of the first edition: An appetizing textbook for a f...
The Segal chronogeometric redshift - a classical analysis
International Nuclear Information System (INIS)
Fairchild, E.E. Jr.; Washington Univ., St. Louis, Mo.
1977-01-01
An error is shown to exist in the Segal chronogeometric redshift theory. The redshift distance relation of z=tan 2 (d/2R) derived by Segal using quantum theory violates the classical correspondence limit. The corrected result derived using simple classical arguments is z=tan 2 (d/R). This result gives the same predictions for small redshift objects but differs for large redshift objects such as quasars. The difference is shown to be caused by inconsistencies in the quantum derivation. Correcting these makes the quantum result equal to the classical result as one would expect from the correspondence principle. The impact of the correction on the predictions of the theory is discussed. (orig.) [de
The chronicle of the classical electrodynamics
International Nuclear Information System (INIS)
Bassalo, J.M.F.
1984-01-01
In this Chronicle of the classical electrodynamics it is shown how this important branch of classical physics was developed since the mathematical formulation of the electromagnetism empiric laws carried by Maxwell, mainly the laws of Coulomb, Oersted, Ampere, Biot-Savart, Faraday, Henry and Lenz, up to the settlement of the radiation theory, scientific background for the technological development of the wireless telegraphy. Through this chronicle, it is also seen how Maxwell got one of the main results of the past century classical physics - the electromagnetic theory of light -, and how the experimental production of an electromagnetic wave by Hertz, unchained a collection of theoretical papers which explained many experimental results such as dispersion of light, thermical radiation, X-rays and its scattering through the matter. At last, it is still seen that the study of electrodynamics of moving bodies led to the relativity theory, presented by Einstein's famous paper about such subject. (Author) [pt
Quantum and classical optics–emerging links
International Nuclear Information System (INIS)
Eberly, J H; Qian, Xiao-Feng; Qasimi, Asma Al; Ali, Hazrat; Alonso, M A; Gutiérrez-Cuevas, R; Little, Bethany J; Howell, John C; Malhotra, Tanya; Vamivakas, A N
2016-01-01
Quantum optics and classical optics are linked in ways that are becoming apparent as a result of numerous recent detailed examinations of the relationships that elementary notions of optics have with each other. These elementary notions include interference, polarization, coherence, complementarity and entanglement. All of them are present in both quantum and classical optics. They have historic origins, and at least partly for this reason not all of them have quantitative definitions that are universally accepted. This makes further investigation into their engagement in optics very desirable. We pay particular attention to effects that arise from the mere co-existence of separately identifiable and readily available vector spaces. Exploitation of these vector-space relationships are shown to have unfamiliar theoretical implications and new options for observation. It is our goal to bring emerging quantum–classical links into wider view and to indicate directions in which forthcoming and future work will promote discussion and lead to unified understanding. (invited comment)
Classical- and quantum mechanical Coulomb scattering
International Nuclear Information System (INIS)
Gratzl, W.
1987-01-01
Because in textbooks the quantum mechanical Coulomb scattering is either ignored or treated unsatisfactory, the present work attempts to present a physically plausible, mathematically correct but elementary treatment in a way that it can be used in textbooks and lectures on quantum mechanics. Coulomb scattering is derived as a limiting case of a screened Coulomb potential (finite range) within a time dependent quantum scattering theory. The difference in the asymptotic conditions for potentials of finite versus infinite range leads back to the classical Coulomb scattering. In the classical framework many concepts of the quantum theory can be introduced and are useful in an intuitive understanding of the quantum theory. The differences between classical and quantum scattering theory are likewise useful for didactic purposes. (qui)
Quantum dynamics of classical stochastic systems
Energy Technology Data Exchange (ETDEWEB)
Casati, G
1983-01-01
It is shown that one hand Quantum Mechanics introduces limitations to the manifestations of chaotic motion resulting, for the case of the periodically kicked rotator, in the limitation of energy growth; also, as it is confirmed by numerical experiments, phenomena like the exponential instability of orbits, inherent to strongly chaotic systems, are absent here and therefore Quantum Mechanics appear to be more stable and predictable than Classical Mechanics. On the other hand, we have seen that nonrecurrent behavior may arise in Quantum Systems and it is connected to the presence of singular continuous spectrum. We conjecture that the classical chaotic behavior is reflected, at least partially, in the nature of the spectrum and the singular-continuity of the latter may possess a self-similar structure typical of classical chaos.
Comparison of Classical and Quantum Bremsstrahlung
International Nuclear Information System (INIS)
Pratt, R.H.; Uskov, D.B.; Korol, A.V.; Obolensky, O.I.
2003-01-01
Classical features persist in bremsstrahlung at surprisingly high energies, while quantum features are present at low energies. For Coulomb bremsstrahlung this is related to the similar properties of Coulomb scattering. For bremsstrahlung in a screened potential, the low energy spectrum and angular distribution exhibit structures. In quantum mechanics these structures are associated with zeroes of particular angular-momentum transfer matrix elements at particular energies, a continuation of the Cooper minima in atomic photoeffect. They lead to transparency windows in free-free absorption. The trajectories of these zeroes in the plane of initial and final transition energies (bound and continuum) has been explored. Corresponding features have now been seen in classical bremsstrahlung, resulting from reduced contributions from particular impact parameters at particular energies. This has suggested the possibility of a more unified treatment of classical and quantum bremsstrahlung, based on the singularities of the scattering amplitude in angular momentum
Stereotactic Radiosurgery for Classical Trigeminal Neuralgia
Directory of Open Access Journals (Sweden)
Henry Kodrat
2016-04-01
Full Text Available Trigeminal neuralgia is a debilitating pain syndrome with a distinct symptom mainly excruciating facial pain that tends to come and go unpredictably in sudden shock-like attacks. Medical management remains the primary treatment for classical trigeminal neuralgia. When medical therapy failed, surgery with microvascular decompression can be performed. Radiosurgery can be offered for classical trigeminal neuralgia patients who are not surgical candidate or surgery refusal and they should not in acute pain condition. Radiosurgery is widely used because of good therapeutic result and low complication rate. Weakness of this technique is a latency period, which is time required for pain relief. It usually ranges from 1 to 2 months. This review enlightens the important role of radiosurgery in the treatment of classical trigeminal neuralgia.
African Journals Online (AJOL)
2014-05-06
May 6, 2014 ... facilitate and support articulation between the ECT mid-level worker qualification and the professional B EMC degree. Methods. The researchers used an exploratory, sequential mixed-method design, which is characterised by a qualitative phase of research followed by a quantitative phase. This design is ...
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supports medical education and research at institutions in 12 ... (CBE). CapacityPlus, led by IntraHealth International, is the USAID-funded ... acquire public health, clinical, and/or research skills, usually through applied learning in a .... If students were evaluated, indicate the type of student (i.e. medical, dental, nursing, etc.) ...
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abp
2017-01-24
Jan 24, 2017 ... and the specific rotavirus VP4 (P-types) and VP7 (G-types) determined. Results: The .... Centre for Virus Research (CVR) of the Kenya Medical Research. Institute (KEMRI) ... rotavirus dsRNA was run on 10% polyacrylamide resolving gels using a large format .... What is known about this topic. •. Rotavirus is ...
Classical dynamics and its quantum analogues
International Nuclear Information System (INIS)
Park, D.
1979-01-01
In this book the author establishes mathematical connections between classical and quantum mechanics, between ray optics and wave optics. The approach is to consider classical mechanics as a limiting case of quantum mechanics, and ray optics as a limiting case of wave optics. The conceptual background is discussed where necessary, so the reader should be already fairly familiar with it. The main goal of this approach is the revelation that classical and quantum theory are not so different conceptually as one thinks at first exposure. The first chapters recall the basic facts about light waves and light rays and demonstrate the construction of Newtonian orbits from Schroedinger waves. In the following the Lagrangian and Hamiltonian formulation of few-body system is developed showing as often as possible the relations to the corresponding quantum systems. To illustrate the theory planetary motion using perturbation theory is treated in some detail and several calculations in general relativity such as the deflection and retardation of light by the sun and the precession of planetary perikelia are included. The final parts deal with the motions of systems of many particles. The quantum mechanics of rigid bodies is presented in analogy with the classical theory and contrasts are noted. There is also a discussion of the roles of spinors in the two theories. The book is intended as a text in classical mechanics for readers which have already some knowledge in classical and quantum mechanics. It may help to deepen their understanding of the relation between the old and new theory and show something of the ways in which new discoveries are made. (orig.) 891 HJ/orig. 892 BRE
Learning, Realizability and Games in Classical Arithmetic
Aschieri, Federico
2010-12-01
In this dissertation we provide mathematical evidence that the concept of learning can be used to give a new and intuitive computational semantics of classical proofs in various fragments of Predicative Arithmetic. First, we extend Kreisel modified realizability to a classical fragment of first order Arithmetic, Heyting Arithmetic plus EM1 (Excluded middle axiom restricted to Sigma^0_1 formulas). We introduce a new realizability semantics we call "Interactive Learning-Based Realizability". Our realizers are self-correcting programs, which learn from their errors and evolve through time. Secondly, we extend the class of learning based realizers to a classical version PCFclass of PCF and, then, compare the resulting notion of realizability with Coquand game semantics and prove a full soundness and completeness result. In particular, we show there is a one-to-one correspondence between realizers and recursive winning strategies in the 1-Backtracking version of Tarski games. Third, we provide a complete and fully detailed constructive analysis of learning as it arises in learning based realizability for HA+EM1, Avigad's update procedures and epsilon substitution method for Peano Arithmetic PA. We present new constructive techniques to bound the length of learning processes and we apply them to reprove - by means of our theory - the classic result of Godel that provably total functions of PA can be represented in Godel's system T. Last, we give an axiomatization of the kind of learning that is needed to computationally interpret Predicative classical second order Arithmetic. Our work is an extension of Avigad's and generalizes the concept of update procedure to the transfinite case. Transfinite update procedures have to learn values of transfinite sequences of non computable functions in order to extract witnesses from classical proofs.
Beam structures classical and advanced theories
Carrera, Erasmo; Petrolo, Marco
2011-01-01
Beam theories are exploited worldwide to analyze civil, mechanical, automotive, and aerospace structures. Many beam approaches have been proposed during the last centuries by eminent scientists such as Euler, Bernoulli, Navier, Timoshenko, Vlasov, etc. Most of these models are problem dependent: they provide reliable results for a given problem, for instance a given section and cannot be applied to a different one. Beam Structures: Classical and Advanced Theories proposes a new original unified approach to beam theory that includes practically all classical and advanced models for be
Hidden invariance of the free classical particle
International Nuclear Information System (INIS)
Garcia, S.
1994-01-01
A formalism describing the dynamics of classical and quantum systems from a group theoretical point of view is presented. We apply it to the simple example of the classical free particle. The Galileo group G is the symmetry group of the free equations of motion. Consideration of the free particle Lagrangian semi-invariance under G leads to a larger symmetry group, which is a central extension of the Galileo group by the real numbers. We study the dynamics associated with this group, and characterize quantities like Noether invariants and evolution equations in terms of group geometric objects. An extension of the Galileo group by U(1) leads to quantum mechanics