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arXiv · 1711.10721

Strange stars in $f(R,\mathcal{T})$ gravity

Debabrata Deb·Farook Rahaman·Saibal Ray·B. K. Guha
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Abstract

In this article we try to present spherically symmetric isotropic strange star model under the framework of $f(R,\mathcal{T})$ theory of gravity. To this end, we consider that the Lagrangian density is an arbitrary linear function of the Ricci scalar $R$ and the trace of the energy momentum tensor~$\mathcal{T}$ given as $f\left(R,\mathcal{T}\right)=R+2χT$. We also assume that the quark matter distribution is governed by the simplest form of the MIT bag model equation of state (EOS) as $p=\frac{1}{3}\left(ρ-4B\right)$, where $B$ is the bag constant. We have obtained an exact solution of the modified form of the the Tolman-Oppenheimer-Volkoff (TOV) equation in the framework of $f(R,\mathcal{T})$ gravity theory and studied the dependence of different physical properties, viz., total mass, radius, energy density and pressure on the chosen values of $χ$. Further, to examine physical acceptability of the proposed stellar model in detail, we conducted different tests, viz. energy conditions, modified TOV equation, mass-radius relation, causality condition etc. We have precisely explained the effects arising due to the coupling of the matter and geometry on the compact stellar system. For a chosen value of the Bag constant we have predicted numerical values of different physical parameters in tabular format for the different strange stars. It is found that as the factor $χ$ increases the strange stars shrink gradually and become less massive to turn into a more compact stellar system. The maximum mass point is well within the observational limits and hence our proposed model is suitable to explain the ultra dense compact stars. For $χ=0$ we retrieve as usual the standard results of general relativity (GR).

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Debabrata Deb, Farook Rahaman, Saibal Ray, B. K. Guha. 2018-04-20. Strange stars in $f(R,\mathcal{T})$ gravity. https://doi.org/10.1088/1475-7516%2F2018%2F03%2F044

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