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Related papers: Dark stars in Starobinsky's model

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Within the framework of $f(R)=R+\alpha R^2$ gravity, we study realistic models of neutron stars, using equations of state compatible with the LIGO constraints. i.e. APR4, MPA1, SLy, and WW1. By numerically solving modified…

High Energy Astrophysical Phenomena · Physics 2020-02-26 Pasquale Feola , Xisco Jimenez Forteza , Salvatore Capozziello , Roberto Cianci , Stefano Vignolo

The current work investigates the structural properties of neutron stars in the presence of a strong magnetic field within the framework of f(R,T) modified gravity, where the matter-geometry coupling leads to deviations from general…

General Relativity and Quantum Cosmology · Physics 2026-03-24 Charul Rathod , M. Mishra , Prasanta Kumar Das

Two alternative theories to dark matter are investigated by testing their ability to describe consistently the dynamics of the Milky Way. The first one refers to a modified gravity theory having a running gravitational constant and the…

Astrophysics of Galaxies · Physics 2015-01-20 P. L. C. de Oliveira , J. A. de Freitas Pacheco , G. Reinisch

We consider the possibility that the dark matter, which is required to explain the dynamics of the neutral hydrogen clouds at large distances from the galactic center, could be in the form of a Bose-Einstein condensate. To study the…

Astrophysics · Physics 2010-10-27 C. G. Boehmer , T. Harko

We investigate anisotropic compact stars comprising two non-interacting fluids: quark matter and condensed dark matter. Using the MIT Bag model equation of state for quark matter and Bose-Einstein Condensate equation of state for dark…

General Relativity and Quantum Cosmology · Physics 2025-05-28 G. Panotopoulos , A. Rincón , I. Lopes

We provide the modified TOV equations for the hydrostatic equilibrium of charged compact stars within the metric $f(R)$ gravitational background. We adopt the MIT bag model EoS for the dense matter and assume a charge distribution where the…

General Relativity and Quantum Cosmology · Physics 2022-09-23 Juan M. Z. Pretel , José D. V. Arbañil , Sergio B. Duarte , Sergio E. Jorás , Ribamar R. R. Reis

We study the effects of dark matter on the structural properties of neutron stars. In particular we investigate how the presence of a dark matter component influences the mass-radius relation, the value of the maximum mass of a neutron star…

High Energy Astrophysical Phenomena · Physics 2025-05-29 Domenico Scordino , Ignazio Bombaci

The understanding of stellar structure represents the crossroads of our theories of the nuclear force and the gravitational interaction under the most extreme conditions observably accessible. It provides a powerful probe of the strong…

General Relativity and Quantum Cosmology · Physics 2020-09-15 Gonzalo J. Olmo , Diego Rubiera-Garcia , Aneta Wojnar

We study the structure of relativistic stars in $\mathcal{R}+\alpha \mathcal{R}^{2}$ theory using the method of matched asymptotic expansion to handle the higher order derivatives in field equations arising from the higher order curvature…

General Relativity and Quantum Cosmology · Physics 2017-10-24 Savaş Arapoğlu , Sercan Çıkıntoğlu , K. Yavuz Ekşi

In this work we apply relativistic mean-field theory in neutron stars assuming that fermionic dark matter is trapped inside the star and interacts directly with neutrons by exchanging Standard Model Higgs bosons. For realistic values of the…

High Energy Physics - Phenomenology · Physics 2017-10-25 Grigoris Panotopoulos , Ilidio Lopes

We study neutron star configurations in a simple shift-symmetric subfamily of degenerate higher-order scalar-tensor (DHOST) theories, whose deviations from General Relativity (GR) are characterized by a single parameter. We compute the…

General Relativity and Quantum Cosmology · Physics 2022-11-09 Hamza Boumaza , David Langlois

We study a specific model of anisotropic strange stars in the modified $f\left(R,\mathcal{T}\right)$-type gravity by deriving solutions to the modified Einstein field equations representing a spherically symmetric anisotropic stellar…

General Relativity and Quantum Cosmology · Physics 2019-05-01 Debabrata Deb , Sergei V. Ketov , S. K. Maurya , Maxim Khlopov , P. H. R. S. Moraes , Saibal Ray

Rotating fermion-boson stars are hypothetical celestial objects that consist of both fermionic and bosonic matter interacting exclusively through gravity. Bosonic fields are believed to arise in certain models of particle physics describing…

General Relativity and Quantum Cosmology · Physics 2024-10-16 Jorge Castelo Mourelle , Christoph Adam , Juan Calderón Bustillo , Nicolas Sanchis-Gual

The Starobinsky model of modified gravity suggested to explain dark energy may be also considered in the astrophysical context. Recently it has been pointed out that in contracting regions curvature oscillations around the GR value may lead…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-29 Dmitry Gorbunov , Anna Tokareva

The literature suggests that dark energy is responsible for the accelerating expansion of the universe due to its negative pressure, therefore, dark energy can be used as a possible option to prevent the gravitational collapse of compact…

General Relativity and Quantum Cosmology · Physics 2025-08-18 Susmita Sarkar , Nayan Sarkar

We develop a theoretical framework to study slowly rotating compact stars in a rather general class of alternative theories of gravity, with the ultimate goal of investigating constraints on alternative theories from electromagnetic and…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Paolo Pani , Emanuele Berti , Vitor Cardoso , Jocelyn Read

Theories on the bosonic nature of dark matter are a promising alternative to the cold dark matter model. Here we consider a dark matter halo in the state of a Bose-Einstein condensate, subject to the gravitation of a black hole. In the low…

General Relativity and Quantum Cosmology · Physics 2023-10-11 Ludovica Dieli , Claudio Conti

It has been suggested that Einstein's theory of General Relativity can be modified to accomodate mismatches between the gravitational field and luminous matter on a wide range of scales. Covariant theories of modified gravity generically…

Astrophysics · Physics 2009-03-31 P. G Ferreira , C. Skordis , C. Zunckel

Gravitational wave astronomy might allow us to detect the coalescence of low-brightness astrophysical compact objects which are extremely difficult to be observed with current electromagnetic telescopes. Besides classical sources like black…

General Relativity and Quantum Cosmology · Physics 2018-12-04 Miguel Bezares , Carlos Palenzuela

We generalise the Buchdahl-Bondi limit for the case of static, spherically symmetric, relativistic compact stars immersed in Schwarzschild vacuum in f(R)-theory of gravity, subject to very generic regularity, thermodynamic stability and…

General Relativity and Quantum Cosmology · Physics 2015-09-09 Rituparno Goswami , Sunil D. Maharaj , Anne Marie Nzioki