Varying Fundamental Constants from a String-inspired Brane World Model

TL;DR

This paper develops cosmological brane models inspired by string theory, incorporating Einstein-Gauss-Bonnet gravity, leading to variable fundamental constants and analyzing their evolution and observational consistency.

Contribution

It introduces a string-inspired brane world model with Einstein-Gauss-Bonnet corrections, deriving cosmological equations with time-varying constants.

Findings

Equations resemble Randall-Sundrum model with variable constants

Models predict cosmological evolution compatible with observations

Demonstrates impact of higher-curvature corrections on cosmology

Abstract

We report results on the construction of cosmological braneworld models in the context of the Einstein-Gauss-Bonnet gravity, which include the leading correction to the Einstein-Hilbert action suggested by superstring theory. We obtain and study the equations governing the dynamics of the standard cosmological models. We find that they can be written in the same form as in the case of the Randall-Sundrum model but with time-varying four-dimensional gravitational and cosmological constants. Finally, we discuss the cosmological evolution predicted by these models and their compatibility with observational data.