Dark energy from bulk matter

TL;DR

This paper explores how bulk matter in braneworld cosmology can induce accelerated expansion and mimic dark energy, including crossing the w=-1 boundary, with potential to simulate Chaplygin gas behavior.

Contribution

It demonstrates that bulk matter pressures can dominate late-time dynamics, leading to accelerated expansion and effective dark energy behavior on the brane.

Findings

Bulk pressures dominate late-time cosmological dynamics.

Bulk matter can produce an effective dark energy equation of state.

Simulation of Chaplygin gas behavior using non-exotic bulk matter.

Abstract

We consider the possibility of getting accelerated expansion and w=-1 crossing in the context of a braneworld cosmological setup, endowed with a bulk energy-momentum tensor. For a given ansatz of the bulk content, we demonstrate that the bulk pressures dominate the dynamics at late times and can lead to accelerated expansion. We also analyze the constraints under which we can get a realistic profile for the effective equation of state and conclude that matter in the bulk has the effect of dark energy on the brane. Furthermore, we show that it is possible to simulate the behavior of a Chaplygin gas using non-exotic bulk matter.