Brane-world cosmological perturbations: a covariant approach

TL;DR

This paper develops a covariant framework for analyzing cosmological perturbations in brane-world models, aiming to connect theories like M theory with observable cosmic microwave background data.

Contribution

It introduces a 1+3-covariant approach to perturbations in brane-world cosmology, facilitating the study of their observational signatures.

Findings

Framework for covariant perturbation analysis in brane-worlds

Application to CMB anisotropy predictions

Potential to test M theory through cosmological observations

Abstract

The standard cosmological model, based on general relativity with an inflationary era, is very effective in accounting for a broad range of observed features of the universe. However, the ongoing puzzles about the nature of dark matter and dark energy, together with the problem of a fundamental theoretical framework for inflation, indicate that cosmology may be probing the limits of validity of general relativity. The early universe provides a testing ground for theories of gravity, since gravitational dynamics can lead to characteristic imprints on the CMB and other cosmological observations. Precision cosmology is in principle a means to constrain and possibly falsify candidate quantum gravity theories like M theory. Generalized Randall-Sundrum brane-worlds provide a phenomenological means to test aspects of M theory. I outline the 1+3-covariant approach to cosmological perturbations in these brane-worlds, and its application to CMB anisotropies.