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arXiv · 2603.25598

An effective cosmological constant as black hole primary hair

Christos Charmousis·Pedro G. S. Fernandes·Mokhtar Hassaine
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Abstract

We study Generalized Proca theories inspired by the recent regularised Proca theory of four-dimensional Gauss-Bonnet gravity. By abandoning the rigid constraints typically imposed by specific regularization schemes, we treat the coefficients of the terms in the action as free parameters. This approach uncovers a broader solution space that admits static and spherically symmetric black hole solutions characterized by primary hair, where, surprisingly, the cosmological constant arises naturally as a constant of integration even in the absence of a bare cosmological term.

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Christos Charmousis, Pedro G. S. Fernandes, Mokhtar Hassaine. 2026-03-26. An effective cosmological constant as black hole primary hair. https://arxiv.org/abs/2603.25598

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