Bardeen-Dirac Stars in AdS Spacetime

TL;DR

This paper constructs and analyzes Bardeen-Dirac Stars in AdS spacetime, revealing how their properties like maximum frequency and extreme behaviors depend on the cosmological constant and magnetic charge.

Contribution

It introduces the first static Bardeen-Dirac Stars in AdS spacetime and explores their properties, including the existence of Frozen Bardeen-Dirac Stars and their dependence on cosmological parameters.

Findings

Maximum frequency of BDSs increases as the cosmological constant decreases.

Existence of extreme Frozen Bardeen-Dirac Stars with critical horizons.

FBDSs disappear as the cosmological constant decreases when magnetic charge is fixed.

Abstract

In this paper, we construct a static spherical symmetric Bardeen-Dirac Stars (BDSs) in the four-dimensional Anti-de Sitter (AdS) spacetime, which consists of the electromagnetic field and Dirac field coupled to gravity. We investigate the ADM mass, Noether charge and light rings of BDSs in AdS spacetime. In asymptotically Minkowski spacetime, the maximum frequency of BDSs is one. However, we observe that the maximum frequency of BDSs increases as the cosmological constant decreases in AdS spacetime. Additionally, BDSs can exhibit extreme behavior at low frequencies, refer to as Frozen Bardeen-Dirac stars (FBDSs) in AdS spacetime. FBDSs have a critical event horizon, where the metric function gtt is very close to zero. The matter is entirely encapsulated by this critical horizon, highly concentrated within it. When the magnetic charge is fixed, the FBDSs gradually disappear as the cosmological constant decreases.