English

Cosmological aspects of a hyperbolic solution in $f(R,T)$ gravity

General Relativity and Quantum Cosmology 2022-05-03 v2

Abstract

This article deals with a cosmological scenario in f(R,T) f(R,T) gravity for a flat FLRW model of the universe. We consider the f(R,T) f(R,T) function as f(R)+f(T) f(R)+f(T) which starts with a quadratic correction of the geometric term f(R) f(R) having structure f(R)=R+αR2 f(R)=R+\alpha R^2 , and a linear matter term f(T)=2λT f(T)=2\lambda T . To achieve the solution of the gravitational field equations in the f(R,T) f(R,T) formalism, we take the form of a geometrical parameter, i.e. scale factor a(t)=sinh1n(βt) a(t)= sinh^{\frac{1}{n}}(\beta t) \cite{cha}, where β \beta and n n are model parameters. An eternal acceleration can be predicted by the model for 0<n<1 0<n<1 , while the cosmic transition from the early decelerated phase to the present accelerated epoch can be anticipated for n1 n\geq 1 . The obtained model facilitate the formation of structure in the Universe according to the Jeans instability condition as our model transits from radiation dominated era to matter dominated era. We study the varying role of the equation of state parameter ω \omega . We analyze our model by studying the behavior of the scalar field and discuss the energy conditions on our achieved solution. We examine the validity of our model via Jerk parameter, Om diagnostic, Velocity of sound and Statefinder diagnostic tools. We investigate the constraints on the model parameter n n and H0 H_0 (Hubble constant) using some observational datasets: SNeIaSNeIa dataset, H(z) H(z) (Hubble parameter) dataset, BAO BAO (Baryon Acoustic Oscillation data) and their combinations as joint observational datasets H(z) H(z) + SNeIa SNeIa and H(z) H(z) + SNeIa SNeIa + BAO BAO . It is testified that the present study is well consistent with these observations. We also perform some cosmological tests and a detailed discussion of the model.

Keywords

Cite

@article{arxiv.1903.08562,
  title  = {Cosmological aspects of a hyperbolic solution in $f(R,T)$ gravity},
  author = {Ritika Nagpal and J. K. Singh and A. Beesham and Hamid Shabani},
  journal= {arXiv preprint arXiv:1903.08562},
  year   = {2022}
}

Comments

23pages, 27 figures