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arXiv · 2602.07990

Finite Element Convergence Analysis For Wave Equations With Time-Dependent Coefficients

Oussama Al Jarroudi·Marcus J. Grote
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Abstract

Error estimates are proved for finite element approximations to the solution of second-order hyperbolic partial differential equations with coefficients varying in both space and time. Optimal rates of convergence in the energy norm are proved for the semi-discrete Galerkin finite element solution by introducing a time-dependent Ritz-like projection. Numerical experiments corroborate the rates of convergence and illustrate the localized wave field enhancement in a chain of time-modulated subwavelength resonators.

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Oussama Al Jarroudi, Marcus J. Grote. 2026-02-08. Finite Element Convergence Analysis For Wave Equations With Time-Dependent Coefficients. https://arxiv.org/abs/2602.07990

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