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arXiv · 2601.03296

Cosmologically Coupled Black Holes with Regular Horizons

Mariano Cadoni·Leonardo de Lima·Mirko Pitzalis·Davi C. Rodrigues·Andrea P. Sanna
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Abstract

We present the most general and exact solution of Einstein's gravity sourced by an anisotropic fluid describing the cosmological embedding (CE) of a static and spherically-symmetric object, including black holes (BHs) or exotic compact objects, without radial energy influx and in an arbitrary Friedmann-Lema\^itre-Robertson-Walker (FLRW) cosmology. This is done fully considering backreaction of the local geometry on the cosmological dynamics. Our solution is free of curvature singularities at the would-be BH event horizon, thus solving a main issue of the CE of BH solutions proposed so far. As a byproduct, we derive a new CE of the Schwarzschild BH - distinct from McVitties's original proposal - that is regular everywhere except at the central singularity.

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Mariano Cadoni, Leonardo de Lima, Mirko Pitzalis, Davi C. Rodrigues, Andrea P. Sanna. 2026-01-05. Cosmologically Coupled Black Holes with Regular Horizons. https://arxiv.org/abs/2601.03296

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