Download or read book Crossover Time in Quantum Boson and Spin Systems written by Gennady P. Berman and published by Springer Science & Business Media. This book was released on 2008-10-04 with total page 279 pages. Available in PDF, EPUB and Kindle. Book excerpt: The authors compare classical and quantum dynamics in the quasiclassical region of parameters and under the condition of unstable (chaotic) classical behavior. They estimate the characteristic time-scale at which classical and quantum solutions start to differ significantly. The method is based on exact equations for time-dependent expectation values in boson and spin coherent states, and applies to rather general Hamiltonians with many degrees of freedom. The authors develop a consistent dynamical theory for quantum nonintegrable Hamiltonians and provide explicit examples of classical-quantum "crossover-time", a very common and fundamental phenomenon in quantum nonintegrable systems. This book can be recommended to graduate students and to specialists.
Download or read book Operational Quantum Physics written by Paul Busch and published by Springer Science & Business Media. This book was released on 2009-01-29 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt: Operational Quantum Physics offers a systematic presentation of quantum mechanics which makes exhaustive use of the full probabilistic structure of this theory. Accordingly the notion of an observable as a positive operator valued (POV) measure is explained in great detail, and the ensuing quantum measurement theory is developed and applied both to a resolution of long-standing conceptual and interpretational puzzles in the foundations of quantum mechanics, and to an analysis of various recent fundamental experiments. The book, or different parts of it, may be of interest to advanced students or researchers in quantum physics, to philosophers of physics, and to mathematicians working in operator valued measures.
Download or read book Quantum Ising Phases and Transitions in Transverse Ising Models written by Bikas K. Chakrabarti and published by Springer Science & Business Media. This book was released on 2008-12-22 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt: Investigations into the zero-temperature phases in various frustrated and random Ising models in a transverse or tunnelling field have caught attention very recently in the context of quantum magnetisation of glasses and other frustrated systems. This book gives a detailed discussion of the various theoretical techniques developed for the study of transverse Ising models and of the results of these studies with regular and random frustration, dilution, randomness, etc. Recent developments in the studies on their (quantum) relaxational dynamics, such as in quantum hysteresis, are also treated. The detailed presentation of original results and the reviews given here are expected to inspire further research in the exciting field of quantum many-body systems with randomness and frustration.
Download or read book Translation Group and Particle Representations in Quantum Field Theory written by Hans-Jürgen Borchers and published by Springer Science & Business Media. This book was released on 2008-11-30 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: At the time I learned quantum field theory it was considered a folk theo rem that it is easy to construct field theories fulfilling either the locality or the spectrum condition. The construction of an example for the latter case is particularly easy. Take for instance an irreducible representation of the Poincare group with positive energy, and as an algebra of observables all compact operators in that representation space. This algebra of observables is even an asymptotically Abelian algebra. Since it has only a single repre sentation - except for multiples of this one - it is hardly possible to replace locality in order to obtain a theory with a reasonable physical structure. This example shows that it is not sufficient to replace locality by asymptotic Abelian-ness. The construction of a theory fulfilling locality without a pos itive energy representation was first done by Doplicher, Regge, and Singer [DRS]. However, modern investigations on the locality ideal in the algebra oftest functions, started by Alcantara and Yngvason [AY], seem to indicate that this is a general feature; this means that most of the algebras of ob servables fulfilling the locality condition will not have representations that also fulfil the spectrum condition. This discussion shows that quantum field theory becomes a subject of interest only if both conditions are satisfied at the same time.
Download or read book Inverse and Algebraic Quantum Scattering Theory written by Barnabas Apagyi and published by Springer. This book was released on 2013-12-30 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains three interrelated, beautiful, and useful topics of quantum scattering theory: inverse scattering theory, algebraic scattering theory and supersymmetrical quantum mechanics. The contributions cover such issues as coupled-channel inversions at fixed energy, inversion of pion-nucleon scattering cross-sections into potentials, inversions in neutron and x-ray reflection, 3-dimensional fixed-energy inversion, inversion of electron scattering data affected by dipole polarization, nucleon-nucleon potentials by inversion versus meson-exchange theory, potential reversal and reflectionless impurities in periodic structures, quantum design in spectral, scattering, and decay control, solution hierarchy of Toda lattices, etc.
Download or read book Algebraic Foundations of Non Commutative Differential Geometry and Quantum Groups written by Ludwig Pittner and published by Springer Science & Business Media. This book was released on 2009-01-29 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum groups and quantum algebras as well as non-commutative differential geometry are important in mathematics and considered to be useful tools for model building in statistical and quantum physics. This book, addressing scientists and postgraduates, contains a detailed and rather complete presentation of the algebraic framework. Introductory chapters deal with background material such as Lie and Hopf superalgebras, Lie super-bialgebras, or formal power series. Great care was taken to present a reliable collection of formulae and to unify the notation, making this volume a useful work of reference for mathematicians and mathematical physicists.
Download or read book Oscillator Representation in Quantum Physics written by M. Dineykhan and published by Springer Science & Business Media. This book was released on 2008-12-16 with total page 281 pages. Available in PDF, EPUB and Kindle. Book excerpt: The investigation ofmost problems of quantum physics leads to the solution of the Schrodinger equation with an appropriate interaction Hamiltonian or potential. However, the exact solutions are known for rather a restricted set of potentials, so that the standard eternal problem that faces us is to find the best effective approximation to the exact solution of the Schrodinger equation under consideration. In the most general form, this problem can be formulated as follows. Let a total Hamiltonian H describing a relativistic (quantum field theory) or a nonrelativistic (quantum mechanics) system be given. Our problem is to solve the Schrodinger equation Hlft = Enlftn, n i. e. , to find the energy spectrum {En} and the proper wave functions {lft } n including the'ground state or vacuum lft = 10). The main idea of any ap o proximation technique is to find a decomposition in such a way that Ha describes our physical system in the "closest to H" manner, and the Schrodinger equation HolJt. (O) = E(O)lJt. (O) n n n can be solved exactly. The interaction Hamiltonian HI is supposed to give small corrections to the zero approximation which can be calculated. In this book, we shall consider the problem of a strong coupling regime in quantum field theory, calculations ofpath or functional integrals over the Gaussian measure and spectral problems in quantum mechanics. Let us con sider these problems briefly.
Download or read book Advances in Doublet Mechanics written by Mauro Ferrari and published by Springer Science & Business Media. This book was released on 2008-09-11 with total page 225 pages. Available in PDF, EPUB and Kindle. Book excerpt: The recently proposed, fully multi-scale theory of doublet mechanics offers unprecented opportunities to reconcile the discrete and continuum representations of solids while maintaining a simple analytical format and full compatibility with lattice dynamics and continuum mechanics. In this monograph, a self-contained account of the state of the art in doublet mechanics is presented. Novel results in the elastodynamics of microstructured media are reported, including the identification of a new class of dispersive surface waves, and the presentation of methods for the experimental determination of the essential microstructural parameters. The relationships between doublet mechanics, lattice dynamics, and continuum theories are examined, leading to the identification of the subject areas in which the use of doublet mechanics is most advantageous. These areas include the analysis of domains as diverse as micro-electro-mechanical systems (MEMS), granular and particulate media, nanotubes, and peptide arrays.
Download or read book Indistinguishable Classical Particles written by Alexander Bach and published by Springer Science & Business Media. This book was released on 2008-11-30 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here, the concept of indistinguishability is defined for identical particles by the symmetry of the state, therefore applying to both the classical and the quantum framework. The author describes symmetric statistical operators and classifies these by means of extreme points. He derives de Finettis theorem for the description of infinitely extendible interchangeable random variables, and presents generalisations covering the Poisson limit and the central limit. Finally, a characterisation and interpretation of the integral representations of classical photon states in quantum optics are derived in abelian subalgebras, and unextendible indistinguishable particles are analysed in the context of non-classical photon states. Suitable for mathematical physicists and philosophers of science.
Download or read book Fourth Granada Lectures in Computational Physics written by Pedro L. Garrido and published by Springer. This book was released on 2013-12-20 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt: The methods developed to deal with the computational aspects of physi cal problems are useful in an increasing number of situations, from chem istry, biology and geology to engineering, communications and economics. In fact, computational physics has evolved into a trans-disciplinary field now concerned with the creative use of computers in scientific research. More over, computational methods often help students to develop a deeper under standing of key concepts, and enhance their problem-solving abilities. There fore, computational physics is recognized as having an important educational value, and educators face the task of outlining appropriate curricula to take advantage of these unique features. This is an important motivation for the publication of the contents of the Seminar on Computational Physics which is held in Granada every two years. The seminar aims at bringing together small groups of students and active researchers on different aspects of computational physics. It is part of the doctoral programme of the University of Granada. The proceedings of the previous editions were published as II Granada Lectures in Computational Physics (World Scientific, Singapore 1993) and Third Granada Lectures in Computational Physics (Lecture Notes in Physics, vol. 448, Springer, Berlin 1995) by the same editors. The present book contains the invited lecture notes and a very brief account of contributions by participants at the 4th Granada Seminar on Computational Physics (Granada, Spain, 9-14 September 1996).
Download or read book The Geometry of Dynamical Triangulations written by Jan Ambjorn and published by Springer Science & Business Media. This book was released on 1997-09-18 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book analyses in depth the geometrical aspects of the simplicial quantum gravity model known as the dynamical triangulations approach. The authors provide a compact and convenient account suitable both to introduce the non-expert reader to the spirit of the subject and to provide a well-chosen mathematical route to the heart of the matter for the expert. The techniques described in the book are novel and allow points of current interest in the subject of simplicial quantum gravity to be addressed. The authors discuss piecewise linear manifolds and give entropy estimates of the number of triangulations of 3- and 4-manifolds. Continuum physics is recovered through scaling limits and computer simulation is used to study simplicial quantum gravity extensively. The beginner will appreciate the introduction to the field and the expert the comprehensive account of recent results and developments.
Download or read book From Instability to Intelligence written by Michail Zak and published by Springer Science & Business Media. This book was released on 2008-12-11 with total page 559 pages. Available in PDF, EPUB and Kindle. Book excerpt: So far as the laws of mathematics refer to reality, they are not certain. And so far as they are certain, they do not refer to reality. -A. Einstein The word "instability" in day-to-day language is associated with some thing going wrong or being abnormal: exponential growth of cancer cells, irrational behavior of a patient, collapse of a structure, etc. This book, however, is about "good" instabilities, which lead to change, evolution, progress, creativity, and intelligence; they explain the paradox of irreversi bility in thermodynamics, the phenomena of chaos and turbulence in clas sical mechanics, and non-deterministic (multi-choice) behavior in biological and social systems. The concept of instability is an attribute of dynamical models that de scribe change in time of physical parameters, biological or social events, etc. Each dynamical model has a certain sensitivity to small changes or "errors" in initial values of its variables. These errors may grow in time, and if such growth is of an exponential rate, the behavior of the variable is defined as unstable. However, the overall effect of an unstable variable upon the dynamical system is not necessarily destructive. Indeed, there al ways exists such a group of variables that do not contribute to the energy of the system. In mechanics such variables are called ignorable or cyclic.
Download or read book Chiral Quark Dynamics written by Reinhard Alkofer and published by Springer Science & Business Media. This book was released on 2008-12-04 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: These notes give an introduction to the description of hadrons, i.e., mesons and baryons, within a quark model based on a chirally invariant quantum field theory. Emphasis is put on a didactic approach intended for graduate students with some background on functional integral techniques. Starting from QCD a motivation of a specific form of the effective quark interaction is given. Functional integral bosonization leads to a theory describing successfully meson properties. It possesses solitonic solutions which are identified as baryons. Via functional integral techniques a Faddeev equation for baryons describing them as bound states of a diquark and a quark is derived. Finally, a unification of these two complementary pictures of baryons is proposed.
Download or read book Stretch Twist Fold The Fast Dynamo written by Stephen Childress and published by Springer Science & Business Media. This book was released on 2008-09-11 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of the magnetic fields of the Earth and Sun, as well as those of other planets, stars, and galaxies, has a long history and a rich and varied literature, including in recent years a number of review articles and books dedicated to the dynamo theories of these fields. Against this background of work, some explanation of the scope and purpose of the present monograph, and of the presentation and organization of the material, is therefore needed. Dynamo theory offers an explanation of natural magnetism as a phenomenon of magnetohydrodynamics (MHD), the dynamics governing the evolution and interaction of motions of an electrically conducting fluid and electromagnetic fields. A natural starting point for a dynamo theory assumes the fluid motion to be a given vector field, without regard for the origin of the forces which drive it. The resulting kinematic dynamo theory is, in the non-relativistic case, a linear advection-diffusion problem for the magnetic field. This kinematic theory, while far simpler than its magnetohydrodynamic counterpart, remains a formidable analytical problem since the interesting solutions lack the easiest symmetries. Much ofthe research has focused on the simplest acceptable flows and especially on cases where the smoothing effect of diffusion can be exploited. A close analog is the advection and diffusion of a scalar field by laminar flows, the diffusion being measured by an appropriate Peclet number. This work has succeeded in establishing dynamo action as an attractive candidate for astrophysical magnetism.
Download or read book Introduction to Photon Communication written by Cherif Bendjaballah and published by Springer Science & Business Media. This book was released on 2008-09-11 with total page 203 pages. Available in PDF, EPUB and Kindle. Book excerpt: In recent years, progress in the generation of squeezed states of light, mainly characterized by a reduced noise property, has stimulated important work in relation to their potential use to improve the sensitivity of optical communication systems. These notes are devoted to the detection and information processing of optical signals at very low levels of power. A survey of recent developments from the quantum and classical points of view is presented. Ultimate limits of performance under the criteria of detection and information are established. Some of the results are detailed and may be utilized for the design of practical systems of communication using present technology. The book addresses physicists and engineers interested in present and future developments in optical communications.
Download or read book Impacts on Earth written by Daniel Benest and published by Springer Science & Business Media. This book was released on 1998-03-18 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: Impact phenomena play an essential role in the formation of planets and great influence during their evolution. The first part of this book describes the dynamics that propels asteroids in our solar system; the second part is devoted to impact phenomena; the third inspects terrestrial impacts of asteroids and the hazards due to space debris orbiting our planet. The book addresses scientists working in astronomy, extraterrestrial physics and geophysics. But it should also be of great interest to a learned public that wants to know about the most recent developments in this fast-moving field of theoretical and observational research.
Download or read book A Perspective Look at Nonlinear Media written by Jürgen Parisi and published by Springer Science & Business Media. This book was released on 1998-02-26 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concepts of nonlinear physics are applied to an increasing number of research disciplines. With this volume, the editors offer a selection of articles on nonlinear topics in progress, ranging from physics and chemistry to biology and some applications of social science. The book covers quantum optics, electron crystallization, cellular or flow patterns in fluids and in granular media, biological systems, and the control of brain structures via neuronal excitation. Chemical patterns are looked at both in bulk solutions and on surfaces in heterogeneous systems. From regular structures, the authors turn to the more complex behavior in biology and physics, such as hydrodynamical turbulence, low-dimensional dynamics in solid-state physics, and gravity.
