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arXiv · 2402.14913

Mass inflation without Cauchy horizons

Raúl Carballo-Rubio·Francesco Di Filippo·Stefano Liberati·Matt Visser
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Abstract

Mass inflation is a well established instability, conventionally associated to Cauchy horizons (which are also inner trapping horizons) of stationary geometries, leading to a divergent exponential buildup of energy. We show here that finite (but often large) exponential buildups of energy are generically present for dynamical geometries endowed with slowly-evolving inner trapping horizons, even in the absence of Cauchy horizons. This provides a more general definition of mass inflation based on quasi-local concepts. We also show that various known results in the literature are recovered in the limit in which the inner trapping horizon asymptotically approaches a Cauchy horizon. Our results imply that black hole geometries with non-extremal inner horizons, including the Kerr geometry in general relativity, and non-extremal regular black holes in theories beyond general relativity, can describe dynamical transients but not the long-lived endpoint of gravitational collapse.

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Raúl Carballo-Rubio, Francesco Di Filippo, Stefano Liberati, Matt Visser. 2024-02-22. Mass inflation without Cauchy horizons. https://arxiv.org/abs/2402.14913

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