No Chaos in Brane-World Cosmology

TL;DR

This paper shows that in brane-world cosmology, the initial singularity tends to be isotropic and non-chaotic, contrasting with traditional models that exhibit Mixmaster chaos, suggesting a more uniform early universe.

Contribution

It demonstrates that brane-world models generally lead to isotropic singularities, providing new insights into the early universe's behavior in these scenarios.

Findings

Initial singularity is isotropic in Bianchi type IX models.

Brane-world models lack Mixmaster or chaotic behavior near singularity.

Isotropic singularity acts as a past-attractor in various brane-world models.

Abstract

We discuss the asymptotic dynamical evolution of spatially homogeneous brane-world cosmological models close to the initial singularity. We find that generically the cosmological singularity is isotropic in Bianchi type IX brane-world models and consequently these models do not exhibit Mixmaster or chaotic-like behaviour close to the initial singularity. We argue that this is typical of more general cosmological models in the brane-world scenario. In particular, we show that an isotropic singularity is a past-attractor in all orthogonal Bianchi models and is a local past-attractor in a class of inhomogeneous brane-world models.