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arXiv · 1904.03842

The transmission problem in linear isotropic elasticity

Plamen Stefanov·Gunther Uhlmann·Andras Vasy
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Abstract

We study the isotropic elastic wave equation in a bounded domain with boundary with coefficients having jumps at a nested set of interfaces satisfying the natural transmission conditions there. We analyze in detail the microlocal behavior of such solution like reflection, transmission and mode conversion of S and P waves, evanescent modes, Rayleigh and Stoneley waves. In particular, we recover Knott's equations in this setting. We show that knowledge of the Dirichlet-to-Neumann map determines uniquely the speed of the P and the S waves if there is a strictly convex foliation with respect to them, under an additional condition of lack of full internal reflection of some of the waves.

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Plamen Stefanov, Gunther Uhlmann, Andras Vasy. 2019-04-08. The transmission problem in linear isotropic elasticity. https://doi.org/10.2140/paa.2021.3.109

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