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A mollifier approach to regularize a Cauchy problem for the inhomogeneous Helmholtz equation

  • Pierre Maréchal EMAIL logo , Walter Simo Tao Lee and Faouzi Triki

Abstract

The Cauchy problem for the inhomogeneous Helmholtz equation with non-uniform refraction index is considered. The ill-posedness of this problem is tackled by means of the variational form of mollification. This approach is proved to be consistent, and the proposed numerical simulations are quite promising.

MSC 2010: 35J05; 47A52

Award Identifier / Grant number: ANR-17-CE40-0029

Funding statement: This work is supported in part by the grant ANR-17-CE40-0029 of the French National Research Agency ANR (project MultiOnde).

Acknowledgements

The authors are grateful to N. Alibaud for interesting comments and discussions during the development of the proposed methodology. They also wish to thank T. Le Minh, for nice and fruitful exchanges.

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Received: 2021-05-06
Revised: 2022-06-14
Accepted: 2023-01-23
Published Online: 2023-02-28
Published in Print: 2023-10-01

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