Dilaton Stabilization in Brane Gas Cosmology

TL;DR

This paper investigates the challenge of stabilizing the dilaton field in brane gas cosmology, concluding that within the standard setup, it is not possible to achieve both dilaton stabilization and internal space stability.

Contribution

It demonstrates the inherent difficulty of stabilizing the dilaton while maintaining internal space stability in standard brane gas cosmology models.

Findings

Dilaton cannot be stabilized while keeping internal directions stable.

Standard brane gas cosmology setup is insufficient for simultaneous stabilization.

Results depend on a rolling dilaton and varying gravitational constant.

Abstract

Brane Gas Cosmology is an M-theory motivated attempt to reconcile aspects of the standard cosmology based on Einstein's theory of general relativity. Dilaton gravity, when incorporating winding p-brane states, has verified the Brandenberger--Vafa mechanism --a string-motivated conjecture which explains why only three of the nine spatial dimensions predicted by string theory grow large. Further investigation of this mechanism has argued for a hierarchy of subspaces, and has shown the internal directions to be stable to initial perturbations. These results, however, are dependent on a rolling dilaton, or varying strength of Newton's gravitational constant. In these proceedings we show that it is not possible to stabilize the dilaton and maintain the stability of the internal directions within the standard Brane Gas Cosmology setup.