Higher-order generalized uncertainty principle applied to gravitational baryogenesis

Abstract

The gravitational baryogenesis plays an important role in the study of baryon asymmetry. However, the original mechanism of gravitational baryogenesis in the radiation-dominated era leads to the asymmetry factor η equal to zero, which indicates this mechanism may not generate a sufficient baryon asymmetry in the early Universe. In this paper, we investigate the gravitational baryogenesis for the generation of baryon asymmetry in the early Universe by using a new higher-order generalized uncertainty principle (GUP). It is demonstrated that the entropy and the Friedman equation of the Universe deviate from the original cases due to the effect of the higher-order GUP. Those modifications break the thermal equilibrium of the Universe, and in turn produce a non-zero asymmetry factor η. In particular, our results satisfy all of Sakharov's conditions, which indicates that the scheme of explaining baryon asymmetry in the framework of higher-order GUP is feasible. In addition,combining our theoretical results with the observational data, we constraint the GUP parameter β 0, whose bound is between 8.4 × 1010 ∼ 1.1 × 1013.