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arXiv · 2004.03510

Uniqueness for time-dependent inverse problems with single dynamical data

Abstract

In this work, we investigate the shape identification and coefficient determination associated with two time-dependent partial differential equations in two dimensions. We consider the inverse problems of determining a convex polygonal obstacle and the coefficient appearing in the wave and Schr\"odinger equations from a single dynamical data along with the time. With the far field data, we first prove that the sound speed of the wave equation together with its contrast support of convex-polygon type can be uniquely determined, then establish a uniqueness result for recovering an electric potential as well as its support appearing in the Schr\"odinger equation. As a consequence of these results, we demonstrate a uniqueness result for recovering the refractive index of a medium from a single far field pattern at a fixed frequency in the time-harmonic regime.

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Ibtissem Ben Aïcha, Guanghui Hu, Manmohan Vashisth, Jun Zou. 2020-04-07. Uniqueness for time-dependent inverse problems with single dynamical data. https://doi.org/10.1016/j.jmaa.2020.124910

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