Godel brane

TL;DR

This paper explores the dynamics of a Godel universe within a brane-world context, revealing how bulk interactions influence anisotropy, causality, and the evolution of the universe without phenomenological assumptions.

Contribution

It provides a self-consistent set of equations describing Godel brane evolution and clarifies the relationship between bulk anisotropy and brane properties.

Findings

Bulk interactions influence Godel brane anisotropy

Closed timelike curves persist despite bulk effects

Exact evolution equations for Godel brane dynamics

Abstract

We consider the brane-world generalisation of the Godel universe and analyse its dynamical interaction with the bulk. The exact homogeneity of the standard Godel spacetime no longer holds, unless the bulk is also static. We show how the anisotropy of the Godel-type brane is dictated by that of the bulk and find that the converse is also true. This determines the precise evolution of the nonlocal anisotropic stresses, without any phenomenological assumptions, and leads to a self-consistent closed set of equations for the evolution of the Godel brane. We also examine the causality of the Godel brane and show that the presence of the bulk cannot prevent the appearance of closed timelike curves.