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arXiv · 2505.10934

Black hole thermodynamics probes the equivalence principle

Ana Alonso-Serrano·Luis J. Garay·Marek Liška
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Abstract

The equivalence principle for test gravitational physics strongly constrains dynamics of spacetime, providing a powerful criterion for selecting candidate theories of gravity. However, checking its validity for a particular theory is often a very difficult task. We devise here a simple theoretical criterion for identifying equivalence principle violations in black hole thermodynamics. Employing this criterion, we prove that Lanczos-Lovelock gravity violates the strong equivalence principle, leaving general relativity as the only local, diffeomorphism-invariant theory compatible with it. However, we also show that certain nonlocal expressions for black hole entropy appear to obey the strong equivalence principle.

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Ana Alonso-Serrano, Luis J. Garay, Marek Liška. 2025-05-16. Black hole thermodynamics probes the equivalence principle. https://doi.org/10.1142/s021827182544002x

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