T-dual cosmological solutions in double field theory

TL;DR

This paper explores cosmological solutions in double field theory, revealing T-duality relations between different regimes and proposing a duality between clocks and modes in the universe.

Contribution

It introduces a framework connecting momentum and winding mode dominated universes via T-duality in double field theory.

Findings

Both regimes exhibit asymptotic behaviors related by T-duality.

Imposing different section conditions leads to distinct but related cosmological solutions.

Winding modes can be interpreted as radiation in a Euclidean time framework.

Abstract

We investigate the cosmological solutions coming from the double field theory equations of motion after coupling a matter source to them. Assuming constant dilaton and imposing the section condition with respect to the regular coordinates leads to a universe dominated by momentum modes while imposing the section condition with respect to the dual coordinates naturally leads to a universe dominated by momentum modes. We show that both regimes have asymptotic behaviours related by T-duality. This hints towards defining a duality between the clocks considered in each regime and interpreting winding modes as being radiation from the point of view of a Euclidean time.