String Cosmology and Chaos

TL;DR

This paper reviews key aspects of string cosmology, including stochastic pre-big bang models, chaos in cosmological solutions, and their connection to hyperbolic Kac-Moody algebras, highlighting the complex dynamics in early universe models.

Contribution

It introduces the link between chaos in string cosmology solutions and the Weyl groups of hyperbolic Kac-Moody algebras, offering new insights into the mathematical structure of these models.

Findings

Chaos is inherent in generic solutions of string effective actions.

The link between chaos and Kac-Moody algebra Weyl groups is established.

The stochastic approach provides a framework for pre-big bang scenarios.

Abstract

We briefly review three aspects of string cosmology: (1) the ``stochastic'' approach to the pre-big bang scenario, (2) the presence of chaos in the generic cosmological solutions of the tree-level low-energy effective actions coming out of string theory, and (3) the remarkable link between the latter chaos and the Weyl groups of some hyperbolic Kac-Moody algebras. Talk given at the Francqui Colloquium ``Strings and Gravity: Tying the Forces Together'' (Brussels, October 2001).