Graviton-driven Mechanism for Baryogenesis in the Early Universe

It has been suggested in previous literature that a real graviton acquires an effective mass owing to the nonperturbative quantum gravitational effect at the Planck scale regime. As a consequence, real gravitons are strongly bound together to form a film structure as an aggregated body. Given the relevant energy scale, these graviton films must have formed in the very early universe. We demonstrated that the gravitational chiral anomaly induced by the graviton film for a massless chiral fermion leads to baryon and lepton non-conservation, and that the difference between the resulting baryon and lepton numbers is nonzero. Therefore, the difference is not washed out by the sphaleron process. We propose that this graviton-driven baryogenesis is the origin of the matter-antimatter asymmetry. We deduced the expression for the baryon asymmetry parameter that follows from our proposed theory.