Baryogenesis in f ( R , T ) Gravity

Abstract

We study gravitational baryogenesis in the context of f (R, T ) gravity where the gravitational Lagrangian is given by a generic function of the Ricci scalar R and the trace of the stress-energy tensor T . We explore how this type of modified gravity is capable to shed light on the issue of baryon asymmetry in a successful manner. We consider various forms of baryogenesis interaction and discuss the effect of these interaction terms on the baryon to entropy ratio in this setup. We show that baryon asymmetry during the radiation era of the expanding universe can be non-zero in this framework. Then, we calculate the baryon to entropy ratio for some specific f (R, T ) models and by using the observational data, we give some constraints on the parameter spaces of these models.

Gravitational Baryogenesis in Non-Minimal Coupled f(R,T) Gravity

“…This clearly shows that baryon asymmetry factor is non-zero even in a radiation dominated universe (i.e, n B s = 0 when ω = 1 3 ). [3]. This particular choice of M I has been detected in the form of gravitational waves by LIGO.…”

“…A more complete and generalized version of gravitational baryogenesis is presented in Section V. Finally, Section VI contains the conclusion and summary of the present work. momentum tensor T [3]. The action in f (R, T ) gravity is given by…”

“…in which M * represents cutoff scale of the underlying effective theory [3], R and g being Ricci scalar and determinant of the metric respectively. J µ represent baryonic current.…”

“…is the net baryonic chemical potential and g b represents total number of intrnsic degrees of freedom of baryons [3]. Hence the baryon to entropy ratio in an accelerating universe when the temperature (T ) falls below the critical temperature T D is given by [15]…”

“…PACS numbers: 04.50.Kd; 98.80.-k; 98.80.Bp, 47.10.Fg II. OVERVIEW OF f (R, T ) GRAVITYThe late time cosmic acceleration of the universe has been explored and explained by many alternate models of classical or quantum gravity [3]. One of the most interesting theories of modified gravity is the f (R, T ) gravity.…”