String Cosmology backgrounds from Classical String Geometry

TL;DR

This paper proposes a string cosmology model where a gas of closed strings drives the early universe's evolution, leading to a transition from a 10-dimensional state to a universe with 4 large and 6 stabilized dimensions.

Contribution

It introduces a non-perturbative, $ ext{alpha'}$-corrected string cosmology framework with anisotropic backgrounds, advancing understanding of early universe dimensional stabilization.

Findings

Universe evolves from 10 to 4 large dimensions

Incorporates fully $ ext{alpha'}$-corrected equations

Describes three stages of cosmological evolution

Abstract

We introduce a very early universe model based on the thermodynamics of a gas of closed strings in a background which is non-perturbative in $\alpha'$. Upon considering the fully $\alpha'$-corrected equations extended to include certain anisotropic cosmological backgrounds, we describe the evolution of the system in three different stages parametrized by the gas' equation of state. Using standard string thermodynamical arguments, we start with an isotropic 10-dimensional universe inside the string scale and evolve it towards a universe with four large spacetime dimensions and six stabilized internal dimensions in the Einstein frame.