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تسجيل مستخدم جديدExploring physical features of anisotropic strange stars beyond standard maximum mass limit in $fleft(R,mathcal{T}right)$ gravity
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We study a specific model of anisotropic strange stars in the modified $fleft(R,mathcal{T}right)$-type gravity by deriving solutions to the modified Einstein field equations representing a spherically symmetric anisotropic stellar object. We take a standard assumption that $f(R,mathcal{T})=R+2chimathcal{T}$, where $R$ is Ricci scalar, $mathcal{T}$ is the trace of the energy-momentum tensor of matter, and $chi$ is a coupling constant. To obtain our solution to the modified Einstein equations, we successfully apply the `embedding class 1 techniques. We also consider the case when the strange quark matter (SQM) distribution is governed by the simplified MIT bag model equation of state given by $p_r=frac{1}{3}left(rho-4Bright)$, where $B$ is bag constant. We calculate the radius of the strange star candidates by directly solving the modified TOV equation with the observed values of the mass and some parametric values of $B$ and $chi$. The physical acceptability of our solutions is verified by performing several physical tests. Interestingly, besides the SQM, another type of matter distribution originates due to the effect of coupling between the matter and curvature terms in the $fleft(R,mathcal{T}right)$ gravity theory. Our study shows that with decreasing the value of $chi$, the stellar systems under investigations become gradually massive and larger in size, turning them into less dense compact objects. It also reveals that for $chi<0$ the $fleft(R,mathcal{T}right)$ gravity emerges as a suitable theory for explaining the observed massive stellar objects like massive pulsars, super-Chandrasekhar stars and magnetars, etc., which remain obscure in the standard framework of General Relativity (GR).
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We investigate effects of the modified $f(R, mathcal{T})$ gravity on the charged strange quark stars with the standard choice of $f(R, mathcal{T})=R+2chi mathcal{T}$. Those types of stars are supposed to be made of strange quark matter (SQM) whose di
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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 $fleft(R,mathcal{T}right)=R+2chi T$. We also assume that the quark matter distribution is governed by the simplest form of the MIT bag model equation of state (EOS) as $p=frac{1}{3}left(rho-4Bright)$, 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 $chi$. 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 $chi$ 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 $chi=0$ we retrieve as usual the standard results of general relativity (GR).
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