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In this paper we study the shear free spherical symmetric gravitational collapse of charged radiating star. All the physical quantities including pressure, density are regular. Energy conditions are satisfied throughout the interior of the…

General Relativity and Quantum Cosmology · Physics 2023-12-29 Suresh C. Jaryal , Ayan Chatterjee , Akshay Kumar

In this work, we study the existence of strange star in the background of $f(\mathbb{T},\mathcal{T})$ gravity in the Einstein spacetime geometry, where $\mathbb{T}$ is the torsion tensor and $\mathcal{T}$ is the trace of the energy-momentum…

General Relativity and Quantum Cosmology · Physics 2021-10-13 I. G. Salako , M. Khlopov , Saibal Ray , M. Z. Arouko , Pameli Saha , Ujjal Debnath

We consider static spherically symmetric self-gravitating configurations of the perfect fluid within the framework of the torsion-based extended theory of gravity. In particular, we use the covariant formulation of $f(T)$ gravity with $f(T)…

General Relativity and Quantum Cosmology · Physics 2018-10-03 Sasa Ilijic , Marko Sossich

There is a growing interest in investigating modified theories of gravity, primarily, with the aim of explaining the universe's accelerated expansion, which has been confirmed by several independent observations. Compact objects, like…

General Relativity and Quantum Cosmology · Physics 2021-08-16 K Nobleson , Tuhin Malik , Sarmistha Banik

In this paper, we have emphasized the stability analysis of the accelerating cosmological models obtained in $f(T)$ gravity theory. The behavior of the models based on the evolution of the equation of state parameter shows phantom-like…

General Relativity and Quantum Cosmology · Physics 2022-05-25 L. K. Duchaniya , Santosh V Lohakare , B. Mishra , S. K. Tripathy

Recently, the scalar-tensor representation of $f (R,T)$ gravity was used to explore gravitationally induced particle production/annihilation. Using the framework of irreversible thermodynamics of open systems in the presence of matter…

General Relativity and Quantum Cosmology · Physics 2023-10-20 Amine Bouali , Himanshu Chaudhary , Tiberiu Harko , Francisco S. N. Lobo , Taoufik Ouali , Miguel A. S. Pinto

We consider f(R,T) modified theories of gravity, where the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar R and of the trace of the stress-energy tensor T. We obtain the gravitational field equations in the…

General Relativity and Quantum Cosmology · Physics 2011-07-14 Tiberiu Harko , Francisco S. N. Lobo , Shin'ichi Nojiri , Sergei D. Odintsov

Based on a mesoscopic theory we investigate the non-equilibrium dynamics of a sheared nematic liquid, with the control parameter being the shear stress $\sigma_{\mathrm{xy}}$ (rather than the usual shear rate, $\dot\gamma$). To this end we…

Soft Condensed Matter · Physics 2015-05-18 Sabine H. L. Klapp , Siegfried Hess

Hydrodynamic equations are used to identify the final state reached by a freely evolving granular gas above but close to its shear instability. The theory predicts the formation of a two bands shear state with a steady density profile.…

Statistical Mechanics · Physics 2009-11-13 J. Javier Brey , M. J. Ruiz-Montero , A. Dominguez

This paper investigates the energy bounds in modified Gauss-Bonnet gravity with anisotropic background. Locally rotationally symmetric Bianchi type ${I}$ cosmological model in $f(R,G)$ gravity is considered to meet this aim. Primarily, a…

General Physics · Physics 2017-12-07 M. Farasat Shamir , Ayesha Komal

In this paper, we consider static self-gravitating spherical spacetime and determine various anisotropic solutions through the extended gravitational decoupling technique in…

General Relativity and Quantum Cosmology · Physics 2023-01-11 M Sharif , T Naseer

We discuss the Minkowski stability problem in modified gravity by using dynamical system approach. The method to investigate dynamical stability of Minkowski space was proposed. This method was applied for some modified gravity theories,…

General Relativity and Quantum Cosmology · Physics 2015-10-21 Petr V. Tretyakov

We solve the field equations of modified gravity for $f(R)$ model in metric formalism. Further, we obtain the fixed points of the dynamical system in phase space analysis of $f(R)$ models, both with and without the effects of radiation.…

General Relativity and Quantum Cosmology · Physics 2018-01-26 Murli Manohar Verma , Bal Krishna Yadav

In this article, we have analysed the behaviour of scalar field and cosmological constant in $f(R,T)$ theory of gravity. Here, we have considered the simplest form of $f(R,T)$ i.e. $f(R,T)=R+2f(T)$, where $R$ is the Ricci scalar and $T$ is…

General Relativity and Quantum Cosmology · Physics 2016-07-15 G. P. Singh , Binaya K. Bishi , P. K. Sahoo

In this paper, we examined the viability bounds of a higher derivative $f(R,\Box R, T)$ theory through analyzing energy conditions (where $R$ and $T$ are the Ricci scalar and trace of energy momentum tensor, respectively). We take flat…

General Relativity and Quantum Cosmology · Physics 2018-06-26 Z. Yousaf , M. Sharif , M. Ilyas , M. Z. Bhatti

In this work, we get an idea of the existence of compact stars in the background of f(T) modified gravity where T is a scalar torsion. We acquire the equations of motion using anisotropic property within the spherically compact star with…

General Physics · Physics 2019-11-26 Pameli Saha , Ujjal Debnath

We present results on the effect of the stiffness of the equation of state on the dynamical bar-mode instability in rapidly rotating polytropic models of neutron stars in full General Relativity. We determine the change in the threshold for…

General Relativity and Quantum Cosmology · Physics 2015-04-01 Frank Löffler , Roberto De Pietri , Alessandra Feo , Luca Franci , Francesco Maione

The effects of the cosmological constant on the static equilibrium configurations and stability against small radial perturbations of relativistic polytropic spheres are investigated. This study numerically solves the hydrostatic…

General Relativity and Quantum Cosmology · Physics 2020-04-15 José D. V. Arbañil , Pedro H. R. S. Moraes

A linear stability analysis of the hydrodynamic equations with respect to the homogeneous cooling state is carried out to identify the conditions for stability of a granular gas of rough hard spheres. The description is based on the results…

Soft Condensed Matter · Physics 2018-05-10 Vicente Garzó , Andrés Santos , Gilberto M. Kremer

We study the viability conditions for the absence of ghost, gradient and tachyonic instabilities, in scalar-torsion $f(T,\phi)$ gravity theories in the presence of a general barotropic perfect fluid. To describe the matter sector, we use…

General Relativity and Quantum Cosmology · Physics 2021-11-11 Manuel Gonzalez-Espinoza , Giovanni Otalora , Joel Saavedra