The dynamics of coset dimensional reduction

TL;DR

This paper investigates how scalar fields from compactified supergravity on coset spaces can exhibit scaling behavior, analyzing the conditions under which multiple exponential potentials lead to such dynamics.

Contribution

It provides a detailed analysis of the parameter space in coset compactifications of eleven-dimensional supergravity that can produce scaling solutions.

Findings

Certain parameter regions support scaling behavior

Exponential potentials from coset compactifications can lead to assisted dynamics

Exact scaling solutions are limited when many exponentials are present

Abstract

The evolution of multiple scalar fields in cosmology has been much studied, particularly when the potential is formed from a series of exponentials. For a certain subclass of such systems it is possible to get `assisted` behaviour, where the presence of multiple terms in the potential effectively makes it shallower than the individual terms indicate. It is also known that when compactifying on coset spaces one can achieve a consistent truncation to an effective theory which contains many exponential terms, however, if there are too many exponentials then exact scaling solutions do not exist. In this paper we study the potentials arising from such compactifications of eleven dimensional supergravity and analyse the regions of parameter space which could lead to scaling behaviour.