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arXiv · 2411.09917

Inverse problems for a quasilinear hyperbolic equation with multiple unknowns

Yan Jiang·Hongyu Liu·Tianhao Ni·Kai Zhang
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Abstract

We propose and study several inverse boundary problems associated with a quasilinear hyperbolic equation of the form ${c(x)^{-2}}\partial_t^2u=\Delta_g(u+F(x, u))+G(x, u)$ on a compact Riemannian manifold $(M, g)$ with boundary. We show that if $F(x, u)$ is monomial and $G(x, u)$ is analytic in $u$, then $F, G$ and $c$ as well as the associated initial data can be uniquely determined and reconstructed by the corresponding hyperbolic DtN (Dirichlet-to-Neumann) map. Our work leverages the construction of proper Gaussian beam solutions for quasilinear hyperbolic PDEs as well as their intriguing applications in conjunction with light-ray transforms and stationary phase techniques for related inverse problems. The results obtained are also of practical importance in assorted of applications with nonlinear waves.

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Yan Jiang, Hongyu Liu, Tianhao Ni, Kai Zhang. 2024-11-15. Inverse problems for a quasilinear hyperbolic equation with multiple unknowns. https://arxiv.org/abs/2411.09917

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