Crossover-Time in Quantum Boson and Spin Systems

Crossover-Time in Quantum Boson and Spin Systems PDF Author: Gennady P. Berman
Publisher: Springer Science & Business Media
ISBN: 3540484159
Category : Science
Languages : en
Pages : 279

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Book Description
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.

Crossover-Time in Quantum Boson and Spin Systems

Crossover-Time in Quantum Boson and Spin Systems PDF Author: Gennady P. Berman
Publisher: Springer Science & Business Media
ISBN: 3540484159
Category : Science
Languages : en
Pages : 279

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Book Description
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.

From Instability to Intelligence

From Instability to Intelligence PDF Author: Michail Zak
Publisher: Springer Science & Business Media
ISBN: 3540691219
Category : Science
Languages : en
Pages : 559

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Book Description
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.

Chiral Quark Dynamics

Chiral Quark Dynamics PDF Author: Reinhard Alkofer
Publisher: Springer Science & Business Media
ISBN: 3540494545
Category : Science
Languages : en
Pages : 126

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Book Description
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.

Stretch, Twist, Fold: The Fast Dynamo

Stretch, Twist, Fold: The Fast Dynamo PDF Author: Stephen Childress
Publisher: Springer Science & Business Media
ISBN: 3540447784
Category : Science
Languages : en
Pages : 414

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Book Description
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.

Introduction to Photon Communication

Introduction to Photon Communication PDF Author: Cherif Bendjaballah
Publisher: Springer Science & Business Media
ISBN: 3540492062
Category : Science
Languages : en
Pages : 203

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Book Description
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.

Impacts on Earth

Impacts on Earth PDF Author: Daniel Benest
Publisher: Springer Science & Business Media
ISBN: 9783540642091
Category : Science
Languages : en
Pages : 254

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Book Description
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.

A Perspective Look at Nonlinear Media

A Perspective Look at Nonlinear Media PDF Author: Jürgen Parisi
Publisher: Springer Science & Business Media
ISBN: 9783540639954
Category : Science
Languages : en
Pages : 394

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Book Description
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.

Low Magnetic Fields in Anisotropic Superconductors

Low Magnetic Fields in Anisotropic Superconductors PDF Author: Allan J. Greer
Publisher: Springer Science & Business Media
ISBN: 3540492143
Category : Technology & Engineering
Languages : en
Pages : 170

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Book Description
Superconductors have been known about since the turn ofthe century. Recently there has been a renewed interest with the discovery of the new, high-Tc materials since 1986[1]. These compounds become superconducting at much warmer temperatures than any pre viously known. In fact, many of tthem superconduct at temperatures above the boiling point of liquid nitrogen, making the observation of the transition both accessible and inexpensive. It was obvious immediately that these materials could have a tremendous technological impact, or lead to further materials with even higher transitions. For this reason there has been an intense effort by scientists in both academia and industry to study these materials. The scientificand industrial communitieshope to learn what makes these materials work. For, learning how these materials work not only increases mankind's overall knowledge of his world, but could make some person or company quite successful if the information were used and developed correctly.

Algebraic Renormalization

Algebraic Renormalization PDF Author: Olivier Piguet
Publisher: Springer Science & Business Media
ISBN: 3540491929
Category : Science
Languages : en
Pages : 142

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Book Description
The idea of this book originated from two series of lectures given by us at the Physics Department of the Catholic University of Petr6polis, in Brazil. Its aim is to present an introduction to the "algebraic" method in the perturbative renormalization of relativistic quantum field theory. Although this approach goes back to the pioneering works of Symanzik in the early 1970s and was systematized by Becchi, Rouet and Stora as early as 1972-1974, its full value has not yet been widely appreciated by the practitioners of quantum field theory. Becchi, Rouet and Stora have, however, shown it to be a powerful tool for proving the renormalizability of theories with (broken) symmetries and of gauge theories. We have thus found it pertinent to collect in a self-contained manner the available information on algebraic renormalization, which was previously scattered in many original papers and in a few older review articles. Although we have taken care to adapt the level of this book to that of a po- graduate (Ph. D. ) course, more advanced researchers will also certainly find it useful. The deeper knowledge of renormalization theory we hope readers will acquire should help them to face the difficult problems of quantum field theory. It should also be very helpful to the more phenomenology oriented readers who want to famili- ize themselves with the formalism of renormalization theory, a necessity in view of the sophisticated perturbative calculations currently being done, in particular in the standard model of particle interactions.

Chaos, Kinetics and Nonlinear Dynamics in Fluids and Plasmas

Chaos, Kinetics and Nonlinear Dynamics in Fluids and Plasmas PDF Author: Sadruddin Benkadda
Publisher: Springer Science & Business Media
ISBN: 9783540646358
Category : Science
Languages : en
Pages : 462

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Book Description
Over the last few years it has become apparent that fluid turbulence shares many common features with plasma turbulence, such as coherent structures and self-organization phenomena, passive scalar transport and anomalous diffusion. This book gathers very high level, current papers on these subjects. It is intended for scientists and researchers, lecturers and graduate students because of the review style of the papers.