Domain wall universe in the Einstein-Born-Infeld theory

TL;DR

This paper investigates the dynamics of a domain wall universe within Einstein-Born-Infeld charged black hole spacetimes, revealing conditions for bouncing cosmologies and the impact of electrostatic energy on the wall.

Contribution

It introduces the effect of electrostatic energy on the domain wall and analyzes bounce conditions in various black hole spacetime structures within Einstein-Born-Infeld theory.

Findings

A bounce can occur outside the horizon in all spacetime types.

Larger black hole masses reduce the barrier height, prolonging the bounce.

Electrostatic energy significantly influences the wall's cosmological evolution.

Abstract

In this Letter, we discuss the dynamics of a domain wall universe embedded into the charged black hole spacetime of the Einstein-Born-Infeld (EBI) theory. There are four kinds of possible spacetime structures, i.e., those with no horizon, the extremal one, those with two horizons (as the Reissner-Nordstr$\rm{\ddot o}$m black hole), and those with a single horizon (as the Schwarzshild black hole). We derive the effective cosmological equations on the wall. In contrast to the previous works, we take the contribution of the electrostatic energy on the wall into account. By examining the properties of the effective potential, we find that a bounce can always happen outside the (outer) horizon. For larger masses of the black hole, the height of the barrier between the horizon and bouncing point in the effective potential becomes smaller, leading to longer time scales of bouncing process. These results are compared with those in the previous works.