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arXiv · 1903.12636

Recovery of zeroth order coefficients in non-linear wave equations

Ali Feizmohammadi·Lauri Oksanen
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Abstract

This paper is concerned with the resolution of an inverse problem related to the recovery of a scalar (potential) function $V$ from the source to solution map, of the semi-linear equation $(\Box_{g}+V)u+u^3=0$ on a globally hyperbolic Lorentzian manifold $(M,g)$. We first study the simpler model problem where the geometry is the Minkowski space and prove the uniqueness of $V$ through the use of geometric optics and a three-fold wave interaction arising from the cubic non-linearity. Subsequently, the result is generalized to globally hyperbolic Lorentzian manifolds by using Gaussian beams.

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Ali Feizmohammadi, Lauri Oksanen. 2019-03-29. Recovery of zeroth order coefficients in non-linear wave equations. https://doi.org/10.1017/s1474748020000122

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