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On Perturbation and Variation Methods
Proceedings of the Physical Society. Section A, 1953It is pointed out that the notation of the theory of functionals and the theorem in it analogous to Taylor's theorem facilitates a compact discussion of perturbation and variation methods in quantum mechanics, both for bound state and scattering problems.
Makinson, R. E. B., Turner, J. S.
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1999
Abstract This Chapter describes techniques for obtaining approximations to periodic time solutions of nearly linear second-order differential equations subject to a harmonic forcing term, and to limit cycles of autonomous equations.
D W Jordan, P Smith
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Abstract This Chapter describes techniques for obtaining approximations to periodic time solutions of nearly linear second-order differential equations subject to a harmonic forcing term, and to limit cycles of autonomous equations.
D W Jordan, P Smith
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1999
Abstract This Chapter is concerned with approximating to the solutions of differential equations containing a small parameter E in what might be called difficult cases where, for one reason or another, a straightforward expansion of the solution in powers of c is unobtainable or unusable.
D W Jordan, P Smith
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Abstract This Chapter is concerned with approximating to the solutions of differential equations containing a small parameter E in what might be called difficult cases where, for one reason or another, a straightforward expansion of the solution in powers of c is unobtainable or unusable.
D W Jordan, P Smith
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2015
Abstract Chapter 1 discusses the mathematical aspects of the asymptotic theory. It starts with basic definitions, using for this purpose the so-called coordinate asymptotic expansions. Then the chapter turns to asymptotic analysis of integrals and describe, among others, the method of steepest descent. However, the main attention is with
Matthew N. O. Sadiku +1 more
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Abstract Chapter 1 discusses the mathematical aspects of the asymptotic theory. It starts with basic definitions, using for this purpose the so-called coordinate asymptotic expansions. Then the chapter turns to asymptotic analysis of integrals and describe, among others, the method of steepest descent. However, the main attention is with
Matthew N. O. Sadiku +1 more
+4 more sources
2007
Perturbation theory has been one of the most frequently used and most powerful tools of quantum mechanics. The very foundations of relativistic quantum theory—quantum electrodynamics—are perturbative in nature. Many-body perturbation theory has been used for electron correlation treatments since the early days of quantum chemistry, and in more recent ...
Kenneth G. Dyall, Knut Faegri
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Perturbation theory has been one of the most frequently used and most powerful tools of quantum mechanics. The very foundations of relativistic quantum theory—quantum electrodynamics—are perturbative in nature. Many-body perturbation theory has been used for electron correlation treatments since the early days of quantum chemistry, and in more recent ...
Kenneth G. Dyall, Knut Faegri
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Perturbation-based methods for explaining deep neural networks: A survey
Pattern Recognition Letters, 2021Maksims Ivanovs +2 more
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