GAUGE-MEDIATED CURVATURE OF THE FLAT DIRECTIONS DURING PREHEATING

Usually one expects the inflaton field to be coupled to some gauge-cha rged particles allowing for its decay during reheating. Such particles then play the role of messengers for the gauge-mediated supersymmetry breaking during and (shortly) after the inflation and radiatively ind uce soft masses to all other D-flat directions. We show that during th e preheating stage this gauge-mediated soft masses are typically much greater than the Hubble parameter during inflation. The dramatic role is played by the supersymmetry (SUSY) breaking due to the parametric r esonance effect, which ensures that the inflaton predominantly decays into the bosons and not the fermions. The difference in the Fermi-Bose occupation numbers results in the large gauge-mediated soft masses, w hich determine the post-inflationary evolution of the flat directions, suggesting that non-thermal phase transitions mediated by gauge messe ngers may play a crucial role in the Affleck-Dine mechanism for the ge neration of the baryon asymmetry.