Charged Nariai black holes on the dark bubble

TL;DR

This paper models charged Nariai black holes within a braneworld framework derived from a nucleated bubble in AdS$_5$, linking string theory parameters to electromagnetic constants and exploring implications for fundamental physics bounds.

Contribution

It introduces a novel realization of charged Nariai black holes on a dark bubble in a braneworld setup, connecting string theory and black hole physics.

Findings

Derived a relation between the fine structure constant and string coupling.

Linked the black hole model to the dark bubble braneworld scenario.

Discussed potential implications for the Festina Lente bound and neutrino masses.

Abstract

In this paper, we realise the charged Nariai black hole on a braneworld from a nucleated bubble in AdS$_5$, known as the dark bubble model. Geometrically, the black hole takes the form of a cylindrical spacetime pulling on the dark bubble. This is realised by a brane embedding in an AdS$_5$ black string background. Identifying the brane with a D3-brane in string theory allows us to determine a relation between the fine structure constant and the string coupling, $\alpha_\text{EM} = \frac{3}{2} g_s$, which was previously obtained for a microscopic black hole. We also speculate on the consequences for the Festina Lente bound and neutrino masses.