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arXiv · 2611.04856

Boundary determination from the anisotropic elastic Dirichlet-to-Neumann map

Joonas Ilmavirta·Mikko Salo·Hjørdis Schlüter·Daniel Windisch
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Abstract

We show that the Dirichlet-to-Neumann map of the elastic wave equation determines the density and the anisotropic stiffness tensor on the boundary for generic density and stiffness tensor fields. The proof builds on an interplay between microlocal analysis and algebraic geometry. Microlocal analysis yields a construction of special solutions, valid for many real principal type systems, that concentrate near a boundary point. Generic conditions ensure that this construction holds and allow for extraction of information about stiffness tensor and density at the boundary. We also describe the generic sets through algebraic conditions.

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Joonas Ilmavirta, Mikko Salo, Hjørdis Schlüter, Daniel Windisch. 2026-11-03. Boundary determination from the anisotropic elastic Dirichlet-to-Neumann map. https://arxiv.org/abs/2611.04856

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