String-Dominated Cosmology

TL;DR

This paper explores how string theory influences early universe cosmology by analyzing the solutions of string equations of motion in FRW spacetimes, revealing diverse evolutionary scenarios depending on initial conditions.

Contribution

It provides a classification of possible cosmological evolutions governed by low-energy string equations and presents the general solutions for these dynamics.

Findings

Multiple qualitatively distinct cosmological evolutions identified

General solutions to string equations of motion in FRW spacetimes derived

Dependence of evolution on initial conditions and string era duration

Abstract

If string theory controls physics at the string scale, the dynamics of the early universe before the GUT era will be governed by the low-energy string equations of motion. Studying these equations for FRW spacetimes, we find that depending on the initial conditions when the stringy era starts, and on the time when it ends, there are a wide variety of qualitatively distinct types of evolution. We classify these, and present the general solution to the equations of motion.