Four-dimensional Brane-Chern-Simons Gravity and Cosmology

TL;DR

This paper explores a novel 4D brane-Chern-Simons gravity model, deriving cosmological solutions that include accelerated expansion, bouncing universes, and potential geometric origins of dark energy, with implications for cosmology.

Contribution

It introduces a new 4D brane-Chern-Simons gravity framework and derives cosmological solutions with accelerated expansion and bouncing behaviors.

Findings

Found accelerated expansion solutions for flat universes.

Discovered bouncing cosmological solutions.

Identified de Sitter and quintessence behaviors in the model.

Abstract

From the field equations corresponding to a 4-dimensional brane embedded in the 5-dimensional spacetime of the Einstein-Chern-Simons theory for gravity, we find cosmological solutions that describe an accelerated expansion for a flat universe. Apart from a quintessence-type evolution scheme, we obtain a transient phantom evolution, which is not ruled out by the current observational data. Additionally, a bouncing solution is shown. The introduction of a kinetic term in the action shows a de Sitter behavior although the energy density is not constant. A quintessence behavior is also found. We conjecture on a possible geometric origin of dark energy coming from this action.