English
Related papers

Related papers: Tolman IV fluid sphere in bigravity

200 papers

We analyze strong gravitational lensing by a spherically symmetric mass distribution within the Einstein-Straus-de Sitter framework in a spatially open Universe with negative curvature ($k = -1$). Applying the theory to the lensed quasar…

General Relativity and Quantum Cosmology · Physics 2025-10-27 Mourad Guenouche

In the metric approach of $f(R)$ theories of gravity, the fourth-order field equations are often recast as effective Einstein equations in the presence of standard matter and a curvature fluid (which gathers all the extra terms), always in…

General Relativity and Quantum Cosmology · Physics 2020-12-01 Juan M. Z. Pretel , Sergio E. Jorás , Ribamar R. R. Reis

We provide a set of general tools to study the problem of stellar equilibrium in any gravitational theory in which spherically symmetric spacetimes satisfy master field equations taking the form of an equality between an identically…

General Relativity and Quantum Cosmology · Physics 2026-03-26 Julio Arrechea , Raúl Carballo-Rubio , Matt Visser

Seven new solutions to the interior static and spherically symmetric Einstein's field equations (EFE) are found and investigated. These new solutions are a generalisation of the quadratic density fall-off profile of the Tolman VII solution.…

General Relativity and Quantum Cosmology · Physics 2016-05-02 Ambrish M. Raghoonundun

Since the derivation of a well-defined $D\rightarrow 4$ limit for 4 dimensional Einstein Gauss-Bonnet (4DEGB) gravity coupled to a scalar field, there has been interest in testing it as an alternative to Einstein's general theory of…

General Relativity and Quantum Cosmology · Physics 2025-02-11 Michael Gammon , Robert B. Mann , Sarah Rourke

In this paper we present a strange stellar model using Tolman $V$ type metric potential employing simplest form of the MIT bag equation of state (EOS) for the quark matter. We consider that the stellar system is spherically symmetric,…

General Relativity and Quantum Cosmology · Physics 2018-08-08 Dibyendu Shee , Debabrata Deb , Shounak Ghosh , Saibal Ray , B. k. Guha

We solve the dynamical GR equations for the spherically symmetric evolution of compact stars in the vicinity of the maximum mass, for which instability sets in according to linear perturbation theory. The calculations are done with the…

General Relativity and Quantum Cosmology · Physics 2015-08-06 Alessandro Brillante , Igor Mishustin

We solve the Tolman-Oppenheimer-Volkoff equation using an equation of state (EoS) calculated in holographic QCD. The aim is to use compact astrophysical objects like neutron stars as an indicator to test holographic equations of state. We…

High Energy Physics - Phenomenology · Physics 2015-05-30 Youngman Kim , Chang-Hwan Lee , Ik Jae Shin , Mew-Bing Wan

We extract new classes of anisotropic solutions in the framework of mimetic gravity, by applying the Tolman-Finch-Skea metric and a specific anisotropy not directly depending on it, and by matching smoothly the interior anisotropic solution…

General Relativity and Quantum Cosmology · Physics 2023-04-19 G. G. L. Nashed , Emmanuel N. Saridakis

The aim of the research is to look into a new solution for isotropic compact stars in the context of the $f(R,\,T)$ theory of gravity. We used the Buchdahl [H.A. Buchdahl, Phys. Rev. {\bf 116} (1959) 1027] metric potentials as input to deal…

General Relativity and Quantum Cosmology · Physics 2024-03-21 Piyali Bhar , Pramit Rej

We establish the existence of time-dependent solitons in a modified gravity framework, which is defined by the low energy limit of theories with a weakly broken galileon symmetry and a mass term. These are regular vacuum configurations of…

General Relativity and Quantum Cosmology · Physics 2021-10-18 Juan Barranco , Javier Chagoya , Alberto Diez-Tejedor , Gustavo Niz , Armando A. Roque

We study spherically symmetric solutions to the Einstein-Euler equations which model an idealized relativistic neutron star surrounded by vacuum. These are barotropic fluids with a free boundary, governed by an equation of state which sets…

Analysis of PDEs · Mathematics 2021-08-16 Grigorios Fournodavlos , Volker Schlue

Neutron stars are regarded as natural laboratories for the study of dense strong interaction matter. The equation of state (EoS) of dense matter computed in flat spacetime is used to predict the structure of neutron stars by solving the…

General Relativity and Quantum Cosmology · Physics 2022-10-27 Jianing Li , Tao Guo , Jiaxing Zhao , Lianyi He

(Abridged) It is well known that the tidal deformability of a compact star carries important information about the interior equation-of-state (EOS) of the star. The first gravitational-wave event GW170817 from a binary compact star merger…

High Energy Astrophysical Phenomena · Physics 2019-02-14 S. Y. Lau , P. T. Leung , L. -M. Lin

The present work discusses about the existence of compact star model in the context of $f(R,T)$ gravity with $R$ as the Ricci scalar and $T$ as the trace of energy-momentum tensor $T_{\mu \nu}$. The model has been developed by considering…

General Relativity and Quantum Cosmology · Physics 2021-07-05 Piyali Bhar , Pramit Rej , Aisha Siddiqa , Ghulam Abbas

In this article, we provide a pedagogical review of the Tolman-Oppenheimer-Volkoff (TOV) equation and its solutions which describe static, spherically symmetric gaseous stars in general relativity. Our discussion starts with a systematic…

General Relativity and Quantum Cosmology · Physics 2021-06-15 Emmanuel Chavez Nambo , Olivier Sarbach

We revisit static, spherically symmetric perfect-fluid stellar models in General Relativity within the framework of the $1+1+2$ semi-tetrad formalism. For locally rotationally symmetric static spacetimes, the Tolman-Oppenheimer-Volkoff…

General Relativity and Quantum Cosmology · Physics 2026-05-27 Eduardo Bittencourt , Mariam Campbell , Peter K. S. Dunsby , Sergio E. Jorás

Within the metric formalism of $f(R,T,L_m)$ gravity theories, we investigate the hydrostatic equilibrium structure of compact stars taking into account both isotropic and anisotropic pressure. For this purpose, we focus on the $f(R,T,L_m)=…

General Relativity and Quantum Cosmology · Physics 2024-07-08 Juan M. Z. Pretel

In this paper, we consider the mimetic gravitational theory to derive a novel category of anisotropic star models. To end and to put the resulting differential equations into a closed system, the form of the metric potential $g_{rr}$ as…

General Relativity and Quantum Cosmology · Physics 2021-10-11 G. G. L. Nashed

A set of hadronic equations of state (EoSs) derived from relativistic density functional theory and constrained by terrestrial experiments, astrophysical observations, in particular by the GW170817 event, and chiral effective field theory…

High Energy Astrophysical Phenomena · Physics 2019-07-31 Jia Jie Li , Armen Sedrakian
‹ Prev 1 3 4 5 6 7 10 Next ›