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We investigate the nonrotating neutron stars in $f(T)$ gravity with $f(T)=T+alpha T^2$, where $T$ is the torsion scalar in the teleparallel formalism of gravity. In particular, we utilize the SLy and BSk family of equations of state for perfect fluid to describe the neutron stellar matter and search for the effects of the $f(T)$ modification on the models of neutron stars. For positive $alpha$, the modification results in a stronger gravitation exerted on the stellar matter, leading to a smaller stellar mass in comparison to general relativity. Moreover, there seems to be an upper limit for the central density of the neutron stars with $alpha>0$, beyond which the effective $f(T)$ fluid would have a steplike phase transition in density and pressure profiles, collapsing the numerical system. For negative $alpha$, the $f(T)$ modification provides additional support for neutron stars to contain larger amount of matter. We obtain the mass-radius relations of the realistic models of neutron stars and subject them to the joint constraints from the observed massive pulsars PSR J0030+0451, PSR J0740+6620, and PSR J2215+5135, and gravitational wave events GW170817 and GW190814. For BSk19 equation of state, the neutron star model in $f(T)$ gravity can accommodate all the mentioned data when $alphale 3.5 G^2M_odot^2/c^4$. For BSk20, BSk21 and SLy equations of state, the observational data constrain the model parameter $alpha$ to be negative. If one considers the unknown compact object in the event GW190814 not to be a neutron star and hence excludes this dataset, the constraints for BSk20 and BSk21 models can be loosened to $alphale 0.4 G^2M_odot^2/c^4$ and $alphale 1.9 G^2M_odot^2/c^4$, respectively.
Using the observation data of SNeIa, CMB and BAO, we establish two concrete $f(T)$ models with nonminimal torsion-matter coupling extension. We study in detail the cosmological implication of our models and find they are successful in describing the
In the context of f(R)=R + alpha R^2 gravity, we study the existence of neutron and quark stars with no intermediate approximations in the generalised system of Tolman-Oppenheimer-Volkov equations. Analysis shows that for positive alphas the scalar c
In the previous paper, we have constructed two $f(T)$ models with nonminimal torsion-matter coupling extension, which are successful in describing the evolution history of the Universe including the radiation-dominated era, the matter-dominated era,
The paper presents late time cosmology in $f(Q,T)$ gravity where the dark energy is purely geometric in nature. We start by employing a well motivated $f(Q,T)$ gravity model, $f(Q,T)=mQ^{n}+bT$ where $m,n$ and $b$ are model parameters. Additionally w
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