The nature of singularity in multidimensional anisotropic Gauss-Bonnet cosmology with a perfect fluid

TL;DR

This paper explores the behavior of singularities in higher-dimensional anisotropic universes within Gauss-Bonnet gravity, revealing that the nature of singularities depends on the equation of state parameter and dimensionality.

Contribution

It provides analytical solutions for specific conditions and numerical analysis for general cases, highlighting differences between 4+1 and 5+1 dimensions in Gauss-Bonnet cosmology.

Findings

Singularity is isotropic for w > 1/3.

Analytical solutions found for w=1/3.

Differences between 4+1 and 5+1 dimensions discussed.

Abstract

We investigate dynamics of (4+1) and (5+1) dimensional flat anisotropic Universe filled by a perfect fluid in the Gauss-Bonnet gravity. An analytical solutions valid for particular values of the equation of state parameter $w=1/3$ have been found. For other values of $w$ structure of cosmological singularity have been studied numerically. We found that for $w > 1/3$ the singularity is isotropic. Several important differences between (4+1) and (5+1) dimensional cases are discussed.