A Regularized Asymptotic Solution of the Cauchy Problem for the Nonhomogeneous Schroedinger Equation in the Quasiclassical Approximation in the Presence of a Turning Point of the Limit Operator
Author(s):
Alexander Georgievich Eliseev
National Research University "Moscow Power Engineering Institute"
Associate Professor, Department of Higher Mathematics
yeliseevag@mpei.ru
Pavel Vladimirovich Kirichenko
National Research University "Moscow Power Engineering Institute"
Senior Lecturer, Department of Higher Mathematics
kirichenkopv@mpei.ru
Abstract:
The article is devoted to the development of the regularization method by S.A. Lomov
on singularly perturbed problems
in the presence of spectral singularities of the limit operator. In particular,
a regularized asymptotic solution is constructed for the singularly perturbed inhomogeneous
Cauchy problem that arises in the quasiclassical approximation
in the Schroedinger equation in the coordinate representation. The potential energy
profile chosen in the paper leads
to a singularity in the spectrum of the limit operator in the form of a <> turning point.
Based on the ideas of asymptotic integration of problems with unstable spectrum,
S.A. Lomov and A.G. Eliseev, it is indicated how and from
what considerations regularizing functions and additional regularizing operators
should be introduced, the formalism of
the regularization method for the indicated type of singularity is described in detail,
this algorithm is substantiated, and an asymptotic solution of any order with respect to
a small parameter is constructed.
Keywords
- asymptotic solution
- regularization method
- singularly perturbed Cauchy problem
- turning point
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