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arXiv · 2602.08487

Can UV meet IR in the Swiss cheese?

Madina Abilmazhinova·Diana Kulubayeva·Hrishikesh Chakrabarty·Daniele Malafarina
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Abstract

We consider the embedding of regular black holes in an expanding universe and study how the ultraviolet modifications to the Schwarzschild geometry that regularize the black hole singularity affect the exterior universe's expansion rate. We consider several proposals for the regular black hole geometry and obtain the corresponding Friedmann equations for a universe filled only with dust and black holes. We show that different proposals have different implications which may be distinguished. We then test the hypothesis that the UV corrections to the black hole geometry may be responsible for the current phase of accelerated expansion. To this aim we constrain the value of the regular black hole UV cutoff parameter from observations. Interestingly we find that the best fit is obtained by values of the parameter corresponding to regular horizonless compact objects.

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Madina Abilmazhinova, Diana Kulubayeva, Hrishikesh Chakrabarty, Daniele Malafarina. 2026-02-09. Can UV meet IR in the Swiss cheese?. https://arxiv.org/abs/2602.08487

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