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Related papers: Neutron Stars in Rastall Gravity

200 papers

We propose a Lorentz-covariant theory of gravity, and explain its theoretical origins in the problem of time in Newtonian physics. In this retarded gravitation theory (RGT), the gravitational force depends upon both retarded position and…

General Physics · Physics 2015-05-27 C. K. Raju

We present a class of exact solutions of Einstein's gravitational field equations describing spherically symmetric and static anisotropic stellar type configurations. The solutions are obtained by assuming a particular form of the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 M. K. Mak , T. Harko

We study relativistic stars in the simplest model of the de Rham-Gabadadze-Tolley massive gravity which describes the massive graviton without ghost propagating mode. We consider the hydrostatic equilibrium, and obtain the modified…

General Relativity and Quantum Cosmology · Physics 2016-06-15 Taishi Katsuragawa , Shin'ichi Nojiri , Sergei D. Odintsov , Masashi Yamazaki

This is the fourth paper in a series that attempt to put forward a consistent framework for modelling solid regions in neutron stars. Here we turn our attention to axial perturbations of spherically symmetric spacetimes using a gauge…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Max Karlovini , Lars Samuelsson

We investigate the thermal, magnetic and rotational evolution of isolated neutron stars assuming that the dipolar magnetic field is confined to the crust. Our treatment, for the first time, uses a fully general relativistic formalism not…

Astrophysics · Physics 2007-05-23 D. Page , U. Geppert , T. Zannias

In this manuscript, we have identified the dynamical instability constraints of a self-gravitating cylindrical object within the framework of $f(R,T)$ theory of gravity. We have explored the modified field equations and corresponding…

General Physics · Physics 2016-05-18 Z. Yousaf , M. Zaeem ul Haq Bhatti

Spherical neutron star models are studied within tensor-scalar theories of gravity. Particularly, it is shown that, under some conditions on the second derivative of the coupling function and on star's mass, for a given star there exist two…

General Relativity and Quantum Cosmology · Physics 2009-10-31 J. Novak

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…

General Relativity and Quantum Cosmology · Physics 2022-04-27 Rui-Hui Lin , Xiao-Ning Chen , Xiang-Hua Zhai

We study the oscillations of neutron and strange stars in $R^2$ gravity. More precisely the nonradial $f$-modes are examined and the differences with pure general relativity are investigated. Using these results we build several…

General Relativity and Quantum Cosmology · Physics 2015-09-23 Kalin V. Staykov , Daniela D. Doneva , Stoytcho S. Yazadjiev , Kostas D. Kokkotas

Dynamical analysis of spherically symmetric collapsing star surrounding in locally anisotropic environment with expansion-free condition is presented in $f(R,T)$ gravity, where $R$ corresponds to Ricci scalar and $T$ stands for the trace of…

General Relativity and Quantum Cosmology · Physics 2015-04-21 Ifra Noureen , M. Zubair

Gravitational radiation tends to drive gravity modes in rotating neutron stars unstable. For an inviscid star, the instability sets in when the rotation frequency is about 0.7 times the corresponding mode frequency of the nonrotating star.…

Astrophysics · Physics 2009-09-25 Dong Lai

In this paper a quantum-mechanical behaviour of neutrons in gravitational fields is considered. A first estimation is made using the semiclassical approximation, neglecting General Relativity, magnetic and rotation effects, for neutrons in…

Atomic Physics · Physics 2010-12-30 Avas V. Khugaev , Renat A. Sultanov , Dennis Guster

We investigate the evolution of the gravitational potential in Rastall scalar field theories. In a single component model a consistent perturbation theory, formulated in the newtonian gauge, is possible only for $\gamma = 1$, which is the…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-27 J. C. Fabris , M. Hamani Daouda , O. F. Piattella

The Noether Symmetry Approach can be used to construct spherically symmetric solutions in $f({\cal R})$ gravity. Specifically, the Noether conserved quantity is related to the gravitational mass and a gravitational radius that reduces to…

General Relativity and Quantum Cosmology · Physics 2018-04-04 Mariafelicia De Laurentis

We consider neutron star configurations in the scalar-tensor theory of gravity with the coupling between the kinetic term of a scalar field and the Einstein tensor (such the model is a subclass of Horndeski gravity). Neutron stars in this…

General Relativity and Quantum Cosmology · Physics 2023-01-18 Pavel E. Kashargin , Sergey V. Sushkov

In the present work, we investigate the possibility of obtaining stellar interiors for static self-gravitating systems describing an anisotropic matter distribution in the framework of Rastall gravity through gravitational decoupling by…

General Physics · Physics 2020-06-16 S. K. Maurya , Francisco Tello-Ortiz

Rastall's theory is a modification of Einstein's theory of gravity where the covariant divergence of the stress-energy tensor is no more vanishing, but proportional to the gradient of the Ricci scalar. The motivation of this theory is to…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Gabriel F. Silva , Oliver F. Piattella , Julio C. Fabris , Luciano Casarini , Taislane O. Barbosa

The gravitational aether theory is a modification of general relativity that decouples vacuum energy from gravity, and thus can potentially address the cosmological constant problem. The classical theory is distinguishable from general…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-27 Farbod Kamiab , Niayesh Afshordi

The present work is to introduce a new kind of modified gravitational theory, named as $f(\mathcal{R,G,T})$ (also $f(\mathcal{R,T,G})$) gravity, where $\mathcal{R}$ is the Ricci scalar, $\mathcal{G}$ is Gauss-Bonnet invariant and…

General Relativity and Quantum Cosmology · Physics 2021-11-16 M. Ilyas

Recent observations of quasi-periodic oscillations in the aftermath of giant flares in soft gamma-ray repeaters suggest a close coupling between the seismic motion of the crust after a major quake and the modes of oscillations in a…

Astrophysics · Physics 2008-11-26 Lars Samuelsson , Nils Andersson