Impact of f(G,T) and f(R,G) on gravitational baryogenesis and observational bounds

Abstract

The matter–antimatter asymmetry through baryogenesis (and generalized baryogenesis interaction) mechanism for well-known models of f(R,G) gravity (where R,G represent the Ricci scalar curvature and Gauss–Bonnet topological invariant) and f(G,T) (T denotes the trace of the energy momentum tensor) is being examined. This mechanism is based on the charge-parity (CP) violating interaction between the derivative of the Ricci scalar curvature and the baryon matter current, proposed by Davoudiasl et al. (2004). It is found that baryon to entropy ratio for f(G,T) gravity (specific models: f(G,T)=δGm+λT and f(G,T)=δGm+T+ϵT2), lies in the range 6.5−2.5+2.5×10−11 and 4−5+5×10−11. For f(R,G) (f(R,G)=k1R+k2RnGm and f(R,G)=f0R+f1G) models, we also obtain the values of baryon to entropy ratio which are very close to observational data 9×10−11. It is also mentioned here that results of general form of baryogenesis are also consistent with observational bounds for three models of modified theories of gravity.