Challenges and Obstacles for a Bouncing Universe in Brane Models

TL;DR

This paper investigates bouncing cosmological behaviors in brane models within charged AdS black-hole backgrounds, analyzing conditions for singularity-free evolution, inflation, and the effects of black-hole parameters and brane curvature.

Contribution

It provides a detailed analysis of bouncing universe scenarios in brane models, highlighting conditions for singularity avoidance and inflation in various black-hole backgrounds.

Findings

Bouncing behavior occurs under specific charge and mass conditions.

A singularity-free, inflationary era is possible with a cosmological constant.

Black-hole parameters influence the brane's expansion and bounce dynamics.

Abstract

A Brane evolving in the background of a charged AdS black-hole displays in general a bouncing behaviour with a smooth transition from a contracting to an expanding phase. We examine in detail the conditions and consequences of this behaviour in various cases. For a cosmological-constant-dominated Brane, we obtain a singularity-free, inflationary era which is shown to be compatible only with an intermediate-scale fundamental Planck mass. For a radiation-dominated Brane, the bouncing behaviour can occur only for background-charge values exceeding those allowed for non-extremal black holes. For a matter-dominated Brane, the black-hole mass affects the proper volume or the expansion rate of the Brane. We also consider the Brane evolving in an asymmetric background of two distinct charged AdS black hole spacetimes being bounded by the Brane and find that, in the case of an empty critical Brane, bouncing behaviour occurs only if the black-hole mass difference is smaller than a certain value. The effects of a Brane curvature term on the bounce at early and late times are also investigated.