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arXiv · 2604.20320

Counterexamples to the Lorentzian Calder\'on problem

Lauri Oksanen·Miika Sarkkinen
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Abstract

We show that two non-isometric, smooth, globally hyperbolic Lorentzian metrics can have the same hyperbolic Dirichlet-to-Neumann map on an infinite cylinder with timelike boundary.

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Lauri Oksanen, Miika Sarkkinen. 2026-04-22. Counterexamples to the Lorentzian Calder\'on problem. https://arxiv.org/abs/2604.20320

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