Induced superstring cosmologies and moduli stabilization

TL;DR

This paper explores string cosmological solutions with broken supersymmetry via geometrical fluxes, analyzing moduli stabilization, quantum corrections, and the resulting radiation-dominated cosmological evolutions.

Contribution

It extends previous work by analyzing multiple moduli participating in supersymmetry breaking and provides full string-level calculations of the free energy.

Findings

Quantum and thermal corrections are controllable below the Hagedorn temperature.

Moduli not involved in supersymmetry breaking are exponentially suppressed.

The solutions describe a stable, radiation-dominated cosmological era.

Abstract

We extend the analysis of the recently obtained stringy cosmological solutions induced by thermal and quantum effects, once space-time supersymmetry is spontaneously broken by geometrical fluxes. Cases in which more than one modulus participating in the supersymmetry breaking mechanism are investigated. The free energy is obtained at the full string level. In the intermediate cosmological region where the temperature and the supersymmetry breaking scale are sufficiently smaller than the Hagedorn temperature, the quantum and thermal corrections are under control and calculable. The reason is that the contributions to the effective potential of the moduli that are not participating in the supersymmetry breaking are exponentially suppressed. The backreaction on the initially flat background results in many cases into cosmological evolutions, where the dynamics of all complex structure moduli is frozen. The solutions describe effectively a radiation dominated era, where thermal effects are never negligible, even if the temperature tends to zero at late times. We analyze several types of supersymmetry breaking patterns and examine the stability of the corresponding radiation era.