A note on differences between (4+1)- and (5+1)-dimensional anisotropic cosmology in the presence of the Gauss-Bonnet term

TL;DR

This paper compares (4+1) and (5+1)-dimensional anisotropic cosmological models with Gauss-Bonnet terms, revealing significant differences in their transition probabilities between GB-dominated and Einstein-dominated phases.

Contribution

It provides a comparative analysis of (4+1) and (5+1)-dimensional models with Gauss-Bonnet terms, highlighting the impact on transition probabilities in cosmological dynamics.

Findings

Transition probability from GB to Einstein phase is nearly zero in (4+1) dimensions.

Transition probability is about 60% in (5+1) dimensions.

Significant difference in cosmological dynamics between (4+1) and (5+1) models.

Abstract

We investigate a flat anisotropic (5+1)-dimensional cosmological model in the presence of the Gauss-Bonnet (GB) contribution in addition to usual Einstein term in the action. We compared it with (4+1)-dimensional case and found a substantial difference in corresponding cosmological dynamics. This difference is manifested in the probability of the model to have smooth transition from GB-term-dominated to Einstein-term-dominated phases--this probability in a reasonable measure on the initial condition space is almost zero for (4+1) case and about 60% for (5+1) case. We discuss this difference as well as some features of the dynamics of the considered model.