BARYOGENESIS, DOMAIN-WALLS AND THE ROLE OF GRAVITY

It has recently been speculated that global symmetries are broken by g ravity. We propose a scenario for the generation of the baryon asymmet ry in the early Universe in which the domain walls predicted by theori es with discrete symmetries become unstable due to these Planck scale effects. The relative motion of the decaying walls can provide a mecha nism for the departure from thermal equilibrium necessary to have a no nvanishing baryon asymmetry. In particular, we implement this idea wit hin the frameworks of the left-right and quark-lepton symmetric models .