Big Bang Nucleosynthesis and Entropy Evolution in $f(R,T)$ Gravity

Abstract

The present article is devoted to constrain the model parameter $\chi$ for the $f(R,T)=R+\chi T$ gravity model by employing the constraints coming from big bang nucleosynthesis. We solve the field equations and constrain $\chi$ in the range $-0.14{\kappa }^2\le \chi \le 0.84{\kappa }^2$ (where ${\kappa }^2=\frac{8\pi G}{c^4}$) from the primordial abundances of light elements such as helium-4, deuterium and lithium-7. We found the abundances of helium-4 and deuterium agrees with theoretical predictions, however the lithium problem persists for the $f(R,T)$ gravity model. We also investigate the evolution of entropy for the constrained parameter space of $\chi$ for the radiation and dust universe. We report that entropy is constant when $\chi =0$ for the radiation dominated universe, whereas for the dust universe, entropy increases with time. We finally use the constraints to show that $\chi$ has negligible influence on the cold dark matter annihilation cross section.

8 pages, 3 figures, Accepted version at European Physical Journal Plus

References in corpus (13)

• Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
• f(R,T) gravity
• Primordial Nucleosynthesis in the Precision Cosmology Era
• The Primordial Lithium Problem
• Thermodynamic interpretation of the generalized gravity models with geometry - matter coupling
• Modelling wormholes in $f(R,T)$ gravity
• Dark Matter From f(R,T) Gravity
• Non-exotic matter wormholes in a trace of the energy-momentum tensor squared gravity
• Wormholes in $R^2$-gravity within the $f(R,T)$ formalism
• Constraining The Early-Universe Baryon Density And Expansion Rate
• Propagation of Polar Gravitational Waves in f(R,T) Scenario
• Baryogenesis in Nonminimally Coupled $f(R)$ Theories
• Temporally Varying Universal Gravitational "Constant" and Speed of Light in Energy Momentum Squared Gravity

Cited by in corpus (6)

• $f(Q,T)$ gravity models with observational constraints
• Inflation in $f(R,T)$ Gravity
• Late-Time Viscous Cosmology in $f(R,T)$ Gravity
• Constraints on Tsallis Cosmology from Big Bang Nucleosynthesis and the Relic Abundance of Cold Dark Matter Particles
• Swampland dS conjecture in Mimetic $f(R,T)$ gravity
• Redshift Drift in $f(R,T)$ Gravity