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Related papers: Neutron stars in $f(\mathbb{Q})$ gravity

200 papers

We numerically construct compact stars in the scalar-tensor theory of gravity with non-minimal derivative coupling of a scalar field to the curvature and nonzero cosmological constant. There are two free parameters in this model of gravity:…

General Relativity and Quantum Cosmology · Physics 2025-04-08 P. E. Kashargin , A. A. Lebedev , S. V. Sushkov

In the present paper we investigate non-perturbatively and self-consistently the structure of neutron stars in $R$-squared gravity by simultaneously solving the interior and exterior problem. The mass-radius relations are obtained for…

General Relativity and Quantum Cosmology · Physics 2015-06-18 Stoytcho S. Yazadjiev , Daniela D. Doneva , Kostas D. Kokkotas , Kalin V. Staykov

The spacetime around compact objects is an excellent place to study gravity in the strong, nonlinear, dynamical regime where solar system tests cannot account for the effects of large curvature. Understanding the dynamics of this spacetime…

General Relativity and Quantum Cosmology · Physics 2019-09-02 Alexander Saffer , Hector O. Silva , Nico Yunes

Recent observation shows that general relativity (GR) is not valid in the strong regime. $\mathit{f(R)}$ gravity where $\mathit{R}$ is the Ricci scalar, is regarded to be one of good candidates able to cure the anomalies appeared in the…

General Relativity and Quantum Cosmology · Physics 2021-07-01 G. G. L. Nashed , S. Nojiri

A new geometric interpretation for General Relativity (GR) is proposed. We show that in the presence of an arbitrary affine connection, the gravitational field is described as nonmetricity of the affine connection. An affine connection can…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Alexander Poltorak

An intriguing solution that appears in General Relativity (GR) but has not been observed so far is the wormhole. This exotic solution describes a topological bridge connecting two distinct universes or two different points in the same…

General Relativity and Quantum Cosmology · Physics 2022-08-08 Zinnat Hassan , G. Mustafa , Joao R. L. Santos , P. K. Sahoo

We study the structure of neutron stars in perturbative f(R) gravity models with realistic equations of state. We obtain mass-radius relations in a gravity model of the form f(R)=R+\alpha R^2. We find that deviations from the results of…

General Relativity and Quantum Cosmology · Physics 2015-05-18 A. Savas Arapoglu , Cemsinan Deliduman , K. Yavuz Eksi

Motivated by the recent interests in spin$-2$ massive gravitons, we study the structure of neutron star in the context of massive gravity. The modifications of TOV equation in the presence of massive gravity are explored in $4$ and higher…

General Relativity and Quantum Cosmology · Physics 2017-07-25 S. H. Hendi , G. H. Bordbar , B. Eslam Panah , S. Panahiyan

Since the derivation of a well-defined $D\to4$ limit for 4D Einstein-Gauss-Bonnet (4DEGB) gravity coupled to a scalar field, there has been considerable interest in testing it as an alternative to Einstein's general theory of relativity.…

General Relativity and Quantum Cosmology · Physics 2025-04-25 Alejandro Saavedra , Octavio Fierro , Michael Gammon , Robert B. Mann , Guillermo Rubilar

In this work, we systematically derive the Einstein field equations in general relativity and $f(\mathcal{R})$ gravity, the Tolman-Oppenheimer-Volkoff (TOV) equation, and the expressions for axial and polar Tidal Love Numbers (TLNs) for…

General Relativity and Quantum Cosmology · Physics 2023-06-14 Pinaki Roy , Bharat Kumar

In this work, we study the possibility of generalizing solutions of regular black holes with an electric charge, constructed in general relativity, for the $f(G)$ theory, where $G$ is the Gauss-Bonnet invariant. This type of solution arises…

General Relativity and Quantum Cosmology · Physics 2018-08-20 Marcos V. de S. Silva , Manuel E. Rodrigues

In this paper, we study the slowly rotating neutron stars in $f(R, T)$ gravity based on Hartle-Thorne formalism. We first consider the simplest matter-geometry coupled modified gravity, namely $f(R, T)=R+2\chi T$. We compute the mass,…

General Relativity and Quantum Cosmology · Physics 2024-09-16 Masum Murshid , Mehedi Kalam

We present a numerical scheme that solves the initial value problem in full general relativity for a binary neutron star in quasi-equilibrium. While Newtonian gravity allows for a strict equilibrium, a relativistic binary system emits…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Thomas W. Baumgarte , Stuart L. Shapiro , Gregory B. Cook , Mark A. Scheel , Saul A. Teukolsky

We investigate a conservative formulation of $f(R,T)$ gravity motivated by a key limitation of several existing approaches: the gravitational function is often reconstructed from a chosen equation of state, making the gravity sector…

General Relativity and Quantum Cosmology · Physics 2026-05-12 Ronaldo V. Lobato , Geanderson A. Carvalho , Carlos E. C. Montaña , Jose F. Rodriguez-Ruiz

We study the strong gravity regime in viable models of so-called f(R) gravity that account for the observed cosmic acceleration. In contrast with recent works suggesting that very relativistic stars might not exist in these models, we find…

General Relativity and Quantum Cosmology · Physics 2014-11-18 E. Babichev , D. Langlois

We study slowly-rotating neutron stars in ghost-free massive bigravity. This theory modifies General Relativity by introducing a second, auxiliary but dynamical tensor field that couples to matter through the physical metric tensor through…

General Relativity and Quantum Cosmology · Physics 2018-02-14 Andrew Sullivan , Nicolas Yunes

The direct detection of gravitational waves opens new perspectives for measuring properties of gravitationally bound compact objects. It is then important to investigate black holes and neutron stars in alternative theories of gravity,…

General Relativity and Quantum Cosmology · Physics 2017-07-26 Javier Chagoya , Gustavo Niz , Gianmassimo Tasinato

We study solutions of the stellar structure equations for spherically symmetric objects in Palatini $f(R)=R+\alpha R^2$ and $f(R,Q)=R+\alpha R^2+\beta Q$ in the mass-radius region associated to neutron stars. We illustrate the potential…

General Relativity and Quantum Cosmology · Physics 2021-10-20 Georg Herzog , Hèlios Sanchis-Alepuz

We investigate equilibrium configurations of uniformly rotating neutron stars in $R^2$ gravity with axion scalar field for GM1 equation of state (EoS) for nuclear matter. The mass-radius diagram, mass-central energy density are presented…

General Relativity and Quantum Cosmology · Physics 2020-09-09 Artyom V. Astashenok , Sergey D. Odintsov

We investigate the properties of neutron stars within the framework of $f(Q)$ gravity by incorporating rotational effects through a slowly rotating metric. We derive the modified TOV equations and calculate the angular velocity profiles and…

General Relativity and Quantum Cosmology · Physics 2025-12-04 Muhammad Azzam Alwan , Tomohiro Inagaki , S. A. Narawade , B. Mishra