Baryogenesis inf(R)theories of gravity

Abstract

f(R)-theories of gravity are reviewed in the context of the so called gravitational baryogenesis. The latter is a mechanism for generating the baryon asymmetry in the Universe, and relies on the coupling between the Ricci scalar curvature R and the baryon current. Gravity Lagrangians of the form L(R){approx}R{sup n}, where n differs from 1 (the case of the General Relativity) only for tiny deviations of a few percent, are consistent with the current bounds on the observed baryon asymmetry.