Flat Directions and Baryogenesis in Supersymmetric Theories

Flat directions are a generic feature of supersymmetric theories. They are of cosmological interest because they can lead to coherent production of scalars. In the early universe such flat directions could be dangerous due to the potentially large energy density and the late decay of the associated scalars when they have only $1/M_p$ couplings (Polonyi problem). On the other hand, flat directions among the standard model fields can carry baryon number and lead to a possible mechanism for baryogenesis (Affleck Dine baryogenesis). When considering the cosmological consequences of the flat directions, it is important to take into account the soft potential with curvature of order the Hubble constant due to supersymmetry breaking in the early universe. In this talk, we discuss flat directions, their potential cosmological implications focusing on Affleck-Dine baryogenesis, and how the standard picture of their evolution must be modified in the presence of the large supersymmetry breaking in the early universe.