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arXiv · 2609.39664

Spherical thin shells with charge in unimodular gravity

Gabriel R. Bengochea·Ernesto F. Eiroa·Griselda Figueroa-Aguirre
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Abstract

We construct spherically symmetric thin shells in unimodular gravity (UG) and analyze their dynamical stability under radial, symmetry-preserving perturbations. We use the UG junction conditions and adopt non-conservative charged exterior solutions sourced by a radial electric field. As an application, we build charged vacuum bubbles: a Minkowski interior surrounded by a charged thin shell and matched to an exterior UG geometry. The resulting spacetimes are free of event horizons and central singularities, while in de Sitter-like cases a cosmological horizon may exist outside the shell. We compare the stability regions and the matter content with their counterparts in general relativity, finding some differences controlled by the UG non-conservation parameter. This work extends previously published results.

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Gabriel R. Bengochea, Ernesto F. Eiroa, Griselda Figueroa-Aguirre. 2026-09-30. Spherical thin shells with charge in unimodular gravity. https://doi.org/10.1002/asna.70139

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