Charged strange star with Krori–Barua potential in f(R, T) gravity admitting Chaplygin equation of state

Abstract

In present paper a new compact star model in f (R, T ) gravity is obtained where R and T denote the Ricci scalar and the trace of energy-momentum tensor Tµν respectively. To develop the model we consider the spherically symmetric space-time along with anisotropic fluid distribution in presence of electric field with f (R, T ) = R + 2γT where γ is a small positive constant. We have used the Chaplygin equation of state to explore the stellar model. The field equations for f (R, T ) gravity have been solved by employing the Krori-Barua ansatz already reported in literature [J. Phys. A, Math. Gen. 8:508, 1975]. The exterior spacetime is described by Reissner-Nordström line element for smooth matching at the boundary. It is worthwhile to mention here that the values of all the constants involved with this model have been calculated for the strange stars 4U 1538-52 for different values of γ with the help of matching conditions. The acceptability of the model is discussed in details both analytically and graphically by studying the physical attributes of matter density, pressures, anisotropy factor, stability etc. We have also obtained the numerical values in tabular form for central density, surface density, central pressure and cental adiabatic index for different values of γ. The solutions of the field equations in Einstein gravity can be regained by simply putting γ = 0 to our solution. Moreover, the proposed model is shown to be physically admissible and corroborate with experimental observations on strange star candidates such as 4U 1538-52.

Stable and self-consistent charged gravastar model within the framework of $$f(R,\,T)$$ gravity

“…Faraoni [88] revisited the issue of the correct Lagrangian description of a perfect fluid L m = p versus L m = −ρ in relation with modified gravity theories in which galactic luminous matter couples nonminimally to the Ricci scalar and one concluded that the Lagrangians are only equivalent when the fluid couples minimally to gravity and not otherwise. Bhar [84] presented a spherically symmetric isotropic strange star model under the framework of f (R, T ) theory of gravity by assuming L m = ρ. For our present model the energy-momentum tensor is given by…”

“…by taking p r = p t = p in Ref. [84]. Here E(r ) represents the electric field of the charged fluid sphere.…”

“…Particular emphasis was given to obtain different physical features of the stellar object and its significance in describing an expanding universe. In fact our earlier performed investigations on the stellar object under modified gravity [81][82][83][84][85][86] inspired us to consider this alternative formalism to the case of the gravastar, the final stage of the stellar evolution. Here we present the graphical variations of different physical features of the gravastar for an f (R, T ) model.…”

Relativistic compact stars in Tolman spacetime via an anisotropic approach

“…Zubair et al [27] obtained anisotropic compact star models in f (T ) gravity with Tolman-Kuchowicz spacetime. Bhar [28] explored a charged model of compact star in f (R, T ) gravity admitting chaplygin equation of state. Rej and Bhar [29] obtained charged strange star in f (R, T ) gravity with linear equation of state.…”

A New Class of Analytical Solutions Describing Anisotropic Neutron Stars in General Relativity

“…Heintzmann and Hillebrandt [11] showed through a model of relativistic neutron stars at high densities that while the maximum mass for compact stars is limited to 3-4 𝑀 , there is no limited mass for arbitrarily large anisotropy measurements.In recent years, many physicists have studied the effect of anisotropy of matter in compact stars, taking the radial component of pressure is different from tangential component of pressure in compact stars [12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31]. Attempts have also been made to model both charged and uncharged compact star models using the modified theories of gravity [32,33,34,35]. In the study of anisotropic stars, there are two components of pressure, namely, radial pressure 𝑝 𝑟 and tangential pressure 𝑝 𝑡 .…”