Particle-like Solutions of Non-linear Six-vector Field Equations


Book Description

A brief review is given of attempts to formulate a unitary field theory involving the electromagnetic field. This thesis concerns itself with another such attempt, based on a proposal by Dr. H. Schiff for nonlinear six-vector field equations. The static case of these equations has been considered and analytic solutions were obtained for two special forms of the static equation. A third form of the static equation was solved on the LFP -30 computer and studied in some detail. It is shown that the latter solutions describe particles with no charge. For the third form of the equation, three discrete solutions were found on the computer. Using a heuristic expression for the total energy of these particles, a value was obtained for the coupling constant of this field which was of the order of the coupling constant for "strong" interactions. Interaction potentials between the particles were evaluated, using analytic approximations to the computer solutions. A ratio of the energy of the first particle to that of a compound particle composed of the first two particles was found to be comparable to the ratio of pi-meson to nucleon mass.




Nonlinear Fokker-Planck Equations


Book Description

Centered around the natural phenomena of relaxations and fluctuations, this monograph provides readers with a solid foundation in the linear and nonlinear Fokker-Planck equations that describe the evolution of distribution functions. It emphasizes principles and notions of the theory (e.g. self-organization, stochastic feedback, free energy, and Markov processes), while also illustrating the wide applicability (e.g. collective behavior, multistability, front dynamics, and quantum particle distribution). The focus is on relaxation processes in homogeneous many-body systems describable by nonlinear Fokker-Planck equations. Also treated are Langevin equations and correlation functions. Since these phenomena are exhibited by a diverse spectrum of systems, examples and applications span the fields of physics, biology and neurophysics, mathematics, psychology, and biomechanics.




On the Non-linear Electromagnetic Theory F1k,k


Book Description

Abstract. The non-linear electromagnetic theory proposed by Dr. Schiff is investigated. Nbn-Maxwellian plane wave solutions of the field equations, k = - (l + A^) A^ , are obtained. Static, particlelike solutions of the field equations are considered in the absence of a magnetic field. Existence of well behaved solutions, in the case of spherical symmetry, is formally established. The list of known spherically symmetric, neutral and charged particlelike solutions is extended to include "compound" solutions which correspond to an imaginary vector potential in certain (linear) regions of space. Sufficient conditions are derived under which variational approximations yield upper bounds to the Lagrangian associated with the class of field equations Ad = F'(d) . The usual parameter variation method is generalised, in the case of more than one dimension, to admit variation of functions of one of the independent variables. This method is used to obtain approximations to possible nonspherical, odd parity, neutral particlelike eigensolutions of Ad = d - d^. The results, however, seem to give an approximation to the lowest two-particle state rather than a one-particle state of odd parity. A variational principle for charged particlelike solutions is developed and used to obtain approximations to the lowest (in energy) spherically symmetric state. A scheme is suggested whereby integral relations, which are satisfied by integrable solutions of Ad = F T (d), may be generated. The first few such integral relations are derived and are used, in the particular case F'(t) - 4> - t J , to obtain alternate expressions for the energy, / [^-( Vt)"+ F(t) ]d of the system and to test variational approximations to the solutions of the field equation. The dynamical stability of neutral particlelike solutions, against certain dissociation modes, is demonstrated; in particular, against direct dissociation into plane waves and into particles for which ...




Nonlinear Systems, Vol. 1


Book Description

This book is part of a two volume set which presents the analysis of nonlinear phenomena as a long-standing challenge for research in basic and applied science as well as engineering. It discusses nonlinear differential and differential equations, bifurcation theory for periodic orbits and global connections. The integrability and reversibility of planar vector fields and theoretical analysis of classic physical models are sketched. This first volume concentrates on the mathematical theory and computational techniques that are essential for the study of nonlinear science, a second volume deals with real-world nonlinear phenomena in condensed matter, biology and optics.




Nonlinear Wave Equations


Book Description

The theory of nonlinear wave equations in the absence of shocks began in the 1960s. Despite a great deal of recent activity in this area, some major issues remain unsolved, such as sharp conditions for the global existence of solutions with arbitrary initial data, and the global phase portrait in the presence of periodic solutions and traveling waves. This book, based on lectures presented by the author at George Mason University in January 1989, seeks to present the sharpest results to date in this area. The author surveys the fundamental qualitative properties of the solutions of nonlinear wave equations in the absence of boundaries and shocks. These properties include the existence and regularity of global solutions, strong and weak singularities, asymptotic properties, scattering theory and stability of solitary waves. Wave equations of hyperbolic, Schrodinger, and KdV type are discussed, as well as the Yang-Mills and the Vlasov-Maxwell equations. The book offers readers a broad overview of the field and an understanding of the most recent developments, as well as the status of some important unsolved problems. Intended for mathematicians and physicists interested in nonlinear waves, this book would be suitable as the basis for an advanced graduate-level course.




Variational Methods in Nonlinear Field Equations


Book Description

The book analyzes the existence of solitons, namely of finite energy solutions of field equations which exhibit stability properties. The book is divided in two parts. In the first part, the authors give an abstract definition of solitary wave and soliton and we develop an abstract existence theory for hylomorphic solitons, namely for those solitons which minimize the energy for a given charge. In the second part, the authors apply this theory to prove the existence of hylomorphic solitons for some classes of field equations (nonlinear Klein-Gordon-Maxwell equations, nonlinear Schrödinger-Maxwell equations, nonlinear beam equation,..). The abstract theory is sufficiently flexible to be applied to other situations, like the existence of vortices. The books is addressed to Mathematicians and Physicists.







The Optimal Homotopy Asymptotic Method


Book Description

This book emphasizes in detail the applicability of the Optimal Homotopy Asymptotic Method to various engineering problems. It is a continuation of the book “Nonlinear Dynamical Systems in Engineering: Some Approximate Approaches”, published at Springer in 2011 and it contains a great amount of practical models from various fields of engineering such as classical and fluid mechanics, thermodynamics, nonlinear oscillations, electrical machines and so on. The main structure of the book consists of 5 chapters. The first chapter is introductory while the second chapter is devoted to a short history of the development of homotopy methods, including the basic ideas of the Optimal Homotopy Asymptotic Method. The last three chapters, from Chapter 3 to Chapter 5, are introducing three distinct alternatives of the Optimal Homotopy Asymptotic Method with illustrative applications to nonlinear dynamical systems. The third chapter deals with the first alternative of our approach with two iterations. Five applications are presented from fluid mechanics and nonlinear oscillations. The Chapter 4 presents the Optimal Homotopy Asymptotic Method with a single iteration and solving the linear equation on the first approximation. Here are treated 32 models from different fields of engineering such as fluid mechanics, thermodynamics, nonlinear damped and undamped oscillations, electrical machines and even from physics and biology. The last chapter is devoted to the Optimal Homotopy Asymptotic Method with a single iteration but without solving the equation in the first approximation.