Hyperspherical Harmonics Expansion Techniques

Hyperspherical Harmonics Expansion Techniques PDF Author: Tapan Kumar Das
Publisher: Springer
ISBN: 8132223616
Category : Science
Languages : en
Pages : 170

Get Book Here

Book Description
The book provides a generalized theoretical technique for solving the fewbody Schrödinger equation. Straight forward approaches to solve it in terms of position vectors of constituent particles and using standard mathematical techniques become too cumbersome and inconvenient when the system contains more than two particles. The introduction of Jacobi vectors, hyperspherical variables and hyperspherical harmonics as an expansion basis is an elegant way to tackle systematically the problem of an increasing number of interacting particles. Analytic expressions for hyperspherical harmonics, appropriate symmetrisation of the wave function under exchange of identical particles and calculation of matrix elements of the interaction have been presented. Applications of this technique to various problems of physics have been discussed. In spite of straight forward generalization of the mathematical tools for increasing number of particles, the method becomes computationally difficult for more than a few particles. Hence various approximation methods have also been discussed. Chapters on the potential harmonics and its application to Bose-Einstein condensates (BEC) have been included to tackle dilute system of a large number of particles. A chapter on special numerical algorithms has also been provided. This monograph is a reference material for theoretical research in the few-body problems for research workers starting from advanced graduate level students to senior scientists.

Hyperspherical Harmonics Expansion Techniques

Hyperspherical Harmonics Expansion Techniques PDF Author: Tapan Kumar Das
Publisher: Springer
ISBN: 8132223616
Category : Science
Languages : en
Pages : 170

Get Book Here

Book Description
The book provides a generalized theoretical technique for solving the fewbody Schrödinger equation. Straight forward approaches to solve it in terms of position vectors of constituent particles and using standard mathematical techniques become too cumbersome and inconvenient when the system contains more than two particles. The introduction of Jacobi vectors, hyperspherical variables and hyperspherical harmonics as an expansion basis is an elegant way to tackle systematically the problem of an increasing number of interacting particles. Analytic expressions for hyperspherical harmonics, appropriate symmetrisation of the wave function under exchange of identical particles and calculation of matrix elements of the interaction have been presented. Applications of this technique to various problems of physics have been discussed. In spite of straight forward generalization of the mathematical tools for increasing number of particles, the method becomes computationally difficult for more than a few particles. Hence various approximation methods have also been discussed. Chapters on the potential harmonics and its application to Bose-Einstein condensates (BEC) have been included to tackle dilute system of a large number of particles. A chapter on special numerical algorithms has also been provided. This monograph is a reference material for theoretical research in the few-body problems for research workers starting from advanced graduate level students to senior scientists.

Hyperspherical Harmonics And Their Physical Applications

Hyperspherical Harmonics And Their Physical Applications PDF Author: James Emil Avery
Publisher: World Scientific
ISBN: 9813229314
Category : Science
Languages : en
Pages : 300

Get Book Here

Book Description
Hyperspherical harmonics are extremely useful in nuclear physics and reactive scattering theory. However, their use has been confined to specialists with very strong backgrounds in mathematics. This book aims to change the theory of hyperspherical harmonics from an esoteric field, mastered by specialists, into an easily-used tool with a place in the working kit of all theoretical physicists, theoretical chemists and mathematicians. The theory presented here is accessible without the knowledge of Lie-groups and representation theory, and can be understood with an ordinary knowledge of calculus. The book is accompanied by programs and exercises designed for teaching and practical use.

Hyperspherical Harmonics

Hyperspherical Harmonics PDF Author: John S. Avery
Publisher: Springer Science & Business Media
ISBN: 9400923236
Category : Science
Languages : en
Pages : 265

Get Book Here

Book Description
where d 3 3)2 ( L x - -- i3x j3x j i i>j Thus the Gegenbauer polynomials play a role in the theory of hyper spherical harmonics which is analogous to the role played by Legendre polynomials in the familiar theory of 3-dimensional spherical harmonics; and when d = 3, the Gegenbauer polynomials reduce to Legendre polynomials. The familiar sum rule, in 'lrlhich a sum of spherical harmonics is expressed as a Legendre polynomial, also has a d-dimensional generalization, in which a sum of hyper spherical harmonics is expressed as a Gegenbauer polynomial (equation (3-27»: The hyper spherical harmonics which appear in this sum rule are eigenfunctions of the generalized angular monentum 2 operator A , chosen in such a way as to fulfil the orthonormality relation: VIe are all familiar with the fact that a plane wave can be expanded in terms of spherical Bessel functions and either Legendre polynomials or spherical harmonics in a 3-dimensional space. Similarly, one finds that a d-dimensional plane wave can be expanded in terms of HYPERSPHERICAL HARMONICS xii "hyperspherical Bessel functions" and either Gegenbauer polynomials or else hyperspherical harmonics (equations ( 4 - 27) and ( 4 - 30) ) : 00 ik·x e = (d-4)!!A~oiA(d+2A-2)j~(kr)C~(~k'~) 00 (d-2)!!I(0) 2: iAj~(kr) 2:Y~ (["2k)Y (["2) A A=O ). l). l)J where I(O) is the total solid angle. This expansion of a d-dimensional plane wave is useful when we wish to calculate Fourier transforms in a d-dimensional space.

Stochastic Variational Approach to Quantum-Mechanical Few-Body Problems

Stochastic Variational Approach to Quantum-Mechanical Few-Body Problems PDF Author: Yasuyuki Suzuki
Publisher: Springer Science & Business Media
ISBN: 354049541X
Category : Science
Languages : en
Pages : 314

Get Book Here

Book Description
The quantum-mechanical few-body problem is of fundamental importance for all branches of microphysics and it has substantially broadened with the advent of modern computers. This book gives a simple, unified recipe to obtain precise solutions to virtually any few-body bound-state problem and presents its application to various problems in atomic, molecular, nuclear, subnuclear and solid state physics. The main ingredients of the methodology are a wave-function expansion in terms of correlated Gaussians and an optimization of the variational trial function by stochastic sampling. The book is written for physicists and, especially, for graduate students interested in quantum few-body physics.

Hyperspherical Harmonics and Generalized Sturmians

Hyperspherical Harmonics and Generalized Sturmians PDF Author: John S. Avery
Publisher: Springer Science & Business Media
ISBN: 0306469448
Category : Science
Languages : en
Pages : 202

Get Book Here

Book Description
This text explores the connections between the theory of hyperspherical harmonics, momentum-space quantum theory and generalized Sturmian basis functions. It also introduces methods which may be used to solve many-particle problems directly, without the use of the self-consistent-field approximation.; The method of many-electron Sturmians offers an interesting alternative to the usual SCF-CI methods for calculating atomic and molecular structure. When many-electron Sturmians are used, and when the basis potential is chosen to be the attractive potential of the nuclei in the system, the following advantages are offered: the matrix representation of the nuclear attraction potential is diagonal; the kinetic energy term vanishes from the secular equation; the Slater exponents of the atomic orbitals are automatically optimized; convergence is rapid; a correlated solution to the many-electron problem can be obtained directly, without the use of the SCF approximation; and excited states can be obtained with good accuracy.; The text should be of interest to advanced students and research workers in theoretical chemistry, physics and mathematics.

Aspects of Many-Body Effects in Molecules and Extended Systems

Aspects of Many-Body Effects in Molecules and Extended Systems PDF Author: Debashis Mukherjee
Publisher: Springer Science & Business Media
ISBN: 3642613306
Category : Science
Languages : en
Pages : 551

Get Book Here

Book Description
This volume features invited lectures presented in the workshop-cum-symposium on aspects of many-body effects in molecules and extended systems, Calcutta, February 1 - 10, 1988. The organizers invited leading experts to present recent developments of many-body methods as applied to molecules and condensed systems. The panorama portrayed is quite broad, but by no means exhaustive. The emphasis is undoubtedly on a "molecular point of view".

Innovative Computational Methods In Nuclear Many-body Problems - Towards A New Generation Of Physics In Finite Quantum Systems

Innovative Computational Methods In Nuclear Many-body Problems - Towards A New Generation Of Physics In Finite Quantum Systems PDF Author: Hisashi Horiuchi
Publisher: World Scientific
ISBN: 9814544728
Category :
Languages : en
Pages : 554

Get Book Here

Book Description
The recent rapid innovations in supercomputer technology are changing the concepts of numerical calculations employed in solving a wide variety of nuclear many-body problems. The purpose of the XVII RCNP International Symposium on Innovative Computational Methods in Nuclear Many-Body Problems (INNOCOM97) was to discuss the frontiers of various computational methods and to exchange ideas in wide fields of nuclear physics. The subjects discussed at the symposium covered almost all the areas of nuclear physics.

Recent Progress in Few-Body Physics

Recent Progress in Few-Body Physics PDF Author: N. A. Orr
Publisher: Springer Nature
ISBN: 3030323579
Category : Science
Languages : en
Pages : 968

Get Book Here

Book Description
Few-body physics covers a rich and wide variety of phenomena, ranging from the very lowest energy scales of atomic and molecular physics to high-energy particle physics. The papers contained in the present volume provide an apercu of recent progress in the field from both the theoretical and experimental perspectives and are based on work presented at the “22nd International Conference on Few-Body Problems in Physics”. This book is geared towards academics and graduate students involved in the study of systems which present few-body characteristics and those interested in the related mathematical and computational techniques.

Numerical Grid Methods and Their Application to Schrödinger’s Equation

Numerical Grid Methods and Their Application to Schrödinger’s Equation PDF Author: C. Cerjan
Publisher: Springer Science & Business Media
ISBN: 9401582408
Category : Science
Languages : en
Pages : 256

Get Book Here

Book Description
The use of numerical grid methods to solve the Schrodinger equation has rapidly evolved in the past decade.The early attempts to demonstrate the computational viability of grid methods have been largely superseded by applications to specific problems and deeper research into more sophisticated quadrature schemes. Underpinning this research, of course, is the belief that the generic nature of grid methods can enjoy a symbiotic development with advances in computer technology, harnessing this technology in an effective manner. The contributions to this proceedings demonstrate these points in full: several appli cations displayed creative use and extension of existing grid methodology; other research concentrated on the development of new quadrature schemes or mixed numerical meth ods. The research represented ranges from highly specific spectral simulations of van der Waals complexs to general schemes for reactive scattering. The novelty of grid methods in Density Functional Theory calculations should also be highlighted since it represents an alternative to standard basis set expansion techniques and might offer distinct advantages to the standard techniques. A deliberate attempt was made to present research material with more motivational and background discussion than is typical of research publications. It is hoped that these contributed proceedings will be useful to students and researchers outside the field to have a rapid and complete introduction to many of the exciting uses of grid methodology in atomic and molecular physics. Special thanks are due to the NATO Science Committee for its generous support of the activities of this workshop.

Theory And Experiment Heading For New Physics, Procs Of The Int'l Sch Of Subnuclear Physics

Theory And Experiment Heading For New Physics, Procs Of The Int'l Sch Of Subnuclear Physics PDF Author: Antonino Zichichi
Publisher: World Scientific
ISBN: 9814489719
Category : Science
Languages : en
Pages : 690

Get Book Here

Book Description
In August/September 2000, a group of 80 physicists from 53 laboratories in 15 countries met in Erice, Italy, to participate in the 38th Course of the International School of Subnuclear Physics. This book constitutes the proceedings of that meeting. It focuses on the theoretical investigation of several basic unity issues, including: (1) the understanding of gauge theories in both their continuum and lattice versions; (2) the possible existence and relevance of large extra dimensions together with the resultant lowering of the Planck/string scale to the TeV range; (3) the origin and structure of flavour mixing in the quark and lepton (neutrino) sectors.