Magnetized strange quark matter in f ( R, T ) gravity with bilinear and special form of time varying deceleration parameter

Abstract

In this paper, we have studied homogeneous and anisotropic locally rotationally symmetric (LRS) Bianchi type-I model with magnetized strange quark matter (MSQM) distribution and cosmological constant Λ in f (R, T ) gravity where R is the Ricci scalar and T the trace of matter source. The exact solutions of the field equations are obtained under bilinear and special form of time varying deceleration parameter (DP). Firstly, we have considered two specific forms of bilinear DP with a single parameter of the form: q = α(1−t) 1+t and q = − αt 1+t , which leads to the constant or linear nature of the function based on the constant α. Second one is the special form of the DP as q = −1 + β 1+a β . From the results obtained here, one can observe that in the early universe magnetic flux has more effects and it reduces gradually in the later stage. For t → ∞, we get p → −Bc and ρ → Bc. The behaviour of strange quark matter along with magnetic epoch gives an idea of accelerated expansion of the universe as per the observations of the type Ia Supernovae.The theoretical arguments for the late-time cosmic acceleration are being a major issue among cosmologist of the twentieth century. The idea of this accelerated expansion of universe was discovered nearly 20 years ago by observations through Supernovae Ia [1-5], CMB [6,7], baryon acoustic oscillation (BAO) in galaxy clustering [8][9][10] and WMAP [11] etc. To investigate the nature of the universe, modern cosmology continues to test the above predictions, which leads to the refinement of cosmological models. The nature and behaviour of some unknown mechanism of the universe are responsible for this accelerated expansion, commonly referred as dark energy and contains more energy budget of the universe along with negative pressure. It triggers one of the important issue to study the current acceleration of the universe.Instead of resorting the mysterious concept of dark energy, there is an alternative way to reproduce the dynamics of the expanding universe through modified theories of gravity which is an extension of general relativity. These modifications can occur in several ways such as: one can use a base as the torsional formulation of general relativity called the teleparallel gravity equivalent to general relativity [12] e.g. f (T ) gravity, where T is the torsion scalar. On the other hand one can start the curvature formulation of general relativity in Einstein-Hilbert action by replacing the Ricci scalar with its arbitrary functions or even more complicated curvature invariants such as: f (R), f (R, G) gravity, and the latest f (R, T ) gravity proposed by Harko et al. [13]. The matter Lagrangian of f (R, T ) gravity coupled with Ricci scalar R and trace of energy-momentum tensor T . Such Lagrangian with matter content will differ from the Einstein's one. It has much significance to study late-time cosmic acceleration as well as dark energy and dark matter problem [14][15][16][17]. Hypothetically matter plays more fundamental role in the description of gravitational eff...

Radiating Isotropic Homogeneous f(R,G) Gravity Model with Quark and Strange Quark Matter

“…. Hence our results resembles with the work investigated by those of Sahoo at al. (2018), Chirde and Shekh (2018).…”

“…where B c is the bag constant. Recently,Sahoo et al (2018) studied homogeneous and anisotropic locally rotationally symmetric Bianchi type-I model with magnetized strange quark matter together with cosmological constant (Λ) in f (R, T ) gravity by considering two specific forms of bilinear deceleration parameter and obtained in the early universe magnetic flux has more effects and it reduces gradually in the later stage while behavior of strange quark matter along with magnetic epoch gives an idea of accelerated expansion of the universe as per the observations of the type-Ia Supernovae. Chirde and Shekh (2018) investigated plane symmetric cosmological model with quark and strange quark matter in the deformations of the Einsteins theory of general relativity where a proper deformation of general relativity in the ultraviolet regime could play the role of describing the transition between general relativity and quantum gravity and revealed that the strange quark matter gives an idea of existence of dark energy in the universe and supports the observations of the type-Ia Supernovae.…”

Anisotropic solution in phantom cosmology via Noether symmetry approach

“…It gives us the rate of expansion of the universe that q > 0 deceleration, q < 0 acceleration and q = 0 constant rate of expansion. It is noted that there are many studies related to the time varying deceleration parameter for Bianchi type space-time in different gravitational theories [37][38][39]. In our case the deceleration parameter obtained as…”

Bianchi V I_0 Universe with Magnetized Strange Quark Matter in f(R, T) Theory

“…Moreover, Sahoo et al have investigated MSQM in f (R, T ) theory [18]. Besides, some scientists have investigated MSQM and SQM [25][26][27][28][29][30].…”