Dynamics of Moduli and Gaugino Condensates in an Expanding Universe

Abstract

We study dynamical moduli stabilization driven by gaugino condensation in supergravity. In the presence of background radiation, there exists a region of initial conditions leading to successful stabilization. We point out that most of the allowed region corresponds to initial Hubble rate H close to the scale of condensation \Lambda, which is the natural cutoff of the effective theory. We first show that including the condensate dynamics sets a strong bound on the initial conditions. We then find that (complete) decoupling of the condensate happens at H about two orders of magnitude below \Lambda. This bound implies that in the usual scenario with the condensate integrated out, only the vicinity of the minimum leads to stabilization. Finally, we discuss the effects of thermal corrections.