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We study strange stars in the framework of f(R,T) theory of gravity. To provide exact solutions of the field equations it is considered that the gravitational Lagrangian can be expressed as the linear function of the Ricci scalar R and the trace of the stress-energy tensor T, i.e. f(R,T)=R+2χT, where χ is a constant. We also consider that the strange quark matter (SQM) distribution inside the stellar system is governed by the phenomenological MIT bag model equation of state (EOS), given as pr=1/3(ρ-4B), where B is the bag constant. Further, for a specific value of B and observed values of mass of the strange star candidates we obtain the exact solution of the modified Tolman-Oppenheimer-Volkoff (TOV) equation in the framework of f(R,T) gravity and have studied in detail the dependence of the different physical parameters, like the metric potentials, energy density, radial and tangential pressures and anisotropy etc., due to the chosen different values of χ. Likewise in GR, as have been shown in our previous work [Deb et al., Ann. Phys. (Amsterdam) 387, 239 (2017)] in the present work also we find maximum anisotropy at the surface which seems an inherent property of the strange stars in modified f(R,T) theory of gravity. To check the physical acceptability and stability of the stellar system based on the obtained solutions we have performed different physical tests, viz., the energy conditions, Herrera cracking concept, adiabatic index etc. In this work, we also have explained the effects, those are arising due to the interaction between the matter and the curvature terms in f(R,T) gravity, on the anisotropic compact stellar system. It is interesting to note that as the values of χ increase the strange stars become more massive and their radius increase gradually so that eventually they gradually turn into less dense compact objects. The present study reveals that the modified f(R,T) gravity is a suitable theory to explain massive stellar systems like recent magnetars, massive pulsars and super-Chandrasekhar stars, which cannot be explained in the framework of GR. However, for χ=0 the standard results of Einsteinian gravity are retrieved. [ABSTRACT FROM AUTHOR]

The present work is focused on the investigation of the existence of compact structures describing anisotropic matter distributions within the framework of modified gravity theories, specifically f(R,T) gravity theory. Additionally, we have taken f(R,T) as a linear function of the Ricci scalar R and the trace of the energy-momentum tensor T as f(R,T)=R+2χT, where χ is a dimensionless coupling parameter, and the Lagrangian matter Lm=-1/3(2pt+pr), to describe the complete set of field equations for the anisotropic matter distribution. We follow the embedding class I procedure using the Eisland condition to obtain a full space-time description inside the stellar configuration. Once the space-time geometry is specified, we determine the complete solution of modified Einstein equations by using the MIT bag model equation of state pr=1/3(ρ-4B) that describes the strange quark matter (SQM) distribution inside the stellar system, where B denotes a bag constant. The physical validity of our anisotropic solution is confirmed by executing several physical tests. It is worth mentioning that with the help of the observed mass values for the various strange star candidates, we have predicted the exact radii by taking different values for χ and B. These predicted radii show a monotonic decreasing nature as the parameter χ is moved from -0.8 to 0.8 progressively. In this case, our anisotropic stellar system becomes more massive and transforms into more dense compact stars. We also perform a detailed graphical analysis of the compact star. As a result, for χ<0, the current modified f(R,T) gravity seems promising to explain the observed massive compact astrophysical objects, similar to magnetars, massive pulsars, and Chandrasekhar super white dwarfs, which are not justified in the framework of general relativity. Finally, we note that when χ=0, general relativity results for anisotropic matter distributions are recovered. [ABSTRACT FROM AUTHOR]