Cosmology of intersecting brane world models in Gauss-Bonnet gravity

TL;DR

This paper investigates the cosmological dynamics of intersecting brane models within six-dimensional Einstein-Gauss-Bonnet gravity, revealing conditions for standard cosmology and comparing to Randall-Sundrum models.

Contribution

It introduces a novel analysis of intersecting brane worlds in Gauss-Bonnet gravity, deriving cosmological equations and conditions for standard cosmology in specific backgrounds.

Findings

Cosmological equations resemble Randall-Sundrum II in pure AdS6 backgrounds.

Modified cosmological behavior occurs in non-AdS6 backgrounds.

Conditions for standard late-time cosmology are identified in an AdS6 black hole setting.

Abstract

We study the cosmological properties of a codimension two brane world that sits at the intersection between two four branes, in the framework of six dimensional Einstein-Gauss-Bonnet gravity. Due to contributions of the Gauss-Bonnet terms, the junction conditions require the presence of localized energy density on the codimension two defect. The induced metric on this surface assumes a FRW form, with a scale factor associated to the position of the brane in the background; we can embed on the codimension two defect the preferred form of energy density. We present the cosmological evolution equations for the three brane, showing that, for the case of pure AdS$_6$ backgrounds, they acquire the same form of the ones for the Randall-Sundrum II model. When the background is different from pure AdS$_6$, the cosmological behavior is potentially modified in respect to the typical one of codimension one brane worlds. We discuss, in a particular model embedded in an AdS$_6$ black hole, the conditions one should satisfy in order to obtain standard cosmology at late epochs.