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On determining the fractional exponent of the subdiffusion equation

  • Shavkat Alimov EMAIL logo and Ravshan Ashurov ORCID logo
Published/Copyright: February 10, 2025

Abstract

Determining the unknown order of the fractional derivative in differential equations simulating various processes is an important task of modern applied mathematics. In the last decade, this problem has been actively studied by specialists. A number of interesting results with a certain applied significance were obtained. This paper provides a short overview of the most interesting works in this direction. Next, we consider the problem of determining the order of the fractional derivative in the subdiffusion equation, provided that the elliptic operator included in this equation has at least one negative eigenvalue. An asymptotic formula is obtained according to which, knowing the solution at least at one point of the domain under consideration, the required order can be calculated.

MSC 2020: 35R11

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Received: 2024-03-15
Revised: 2024-05-14
Accepted: 2025-01-29
Published Online: 2025-02-10
Published in Print: 2025-04-01

© 2025 Walter de Gruyter GmbH, Berlin/Boston

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