Standard Cosmology on a Self-Tuning Domain Wall

TL;DR

This paper explores the cosmology of a five-dimensional gravity model with a scalar field and anisotropic fluid, demonstrating that under certain assumptions, the resulting cosmology on a self-tuning brane aligns with standard cosmological models.

Contribution

It shows that a static fifth radius and specific scalar field dependence lead to a warp factor and cosmology consistent with previous models, confirming the viability of self-tuning branes.

Findings

Warp factor matches previous models by Kachru, Schulz, and Silverstein

Cosmology on the brane is standard, especially during radiation dominance

Pressure in the fifth dimension vanishes for radiation-dominated branes

Abstract

We investigate the cosmology of (4+1)-dimensional gravity coupled to a scalar field and a bulk anisotropic fluid within the context of the single-brane Randall-Sundrum scenario. Assuming a separable metric, a static fifth radius and the scalar to depend only on the fifth direction, we find that the warp factor is given as in the papers of Kachru, Schulz and Silverstein [hep-th/0001206, hep-th/0002121] and that the cosmology on a self-tuning brane is standard. In particular, for a radiation-dominated brane the pressure in the fifth direction vanishes.