Semiglobal uniqueness for the Lorentzian Calder\'on problem

Lauri Oksanen; Rakesh; Mikko Salo

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arXiv · 2608.13116

Semiglobal uniqueness for the Lorentzian Calder\'on problem

Lauri Oksanen·Rakesh·Mikko Salo

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Abstract

We prove uniqueness in the Lorentzian Calder\'on problem in a semiglobal setting, comparing a potentially large perturbation of the Minkowski metric against a small one. Our proof uses a reduced amount of data, solving a formally determined version of the problem. In contrast to traditional approaches, it employs neither control-theoretic arguments nor a reduction to a geometric inverse problem via microlocal methods or high-frequency solutions. Instead, it relies on distorted plane waves and weighted $L^2$-estimates.

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Lauri Oksanen, Rakesh, Mikko Salo. 2026-08-13. Semiglobal uniqueness for the Lorentzian Calder\'on problem. https://arxiv.org/abs/2608.13116

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