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Related papers: Collapsing spherical stars in f(R) gravity

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The present work includes an analytical investigation of a collapsing spherical star in f (R) gravity. The interior of the collapsing star admits a conformal flatness. Information regarding the fate of the collapse is extracted from the…

General Relativity and Quantum Cosmology · Physics 2018-11-07 Soumya Chakrabarti , Rituparno Goswami , Sunil Maharaj , Narayan Banerjee

The physically realistic model of compact stars undergoing gravitational collapse in $ f(R) $ gravity has been developed. We consider a more general model $ R + f(R) = R + k R^m $ and describe the interior space-time of gravitationally…

General Relativity and Quantum Cosmology · Physics 2022-05-17 Jay Solanki

Several f(R) modified gravity models have been proposed which realize the correct cosmological evolution and satisfy solar system and laboratory tests. Although nonrelativistic stellar configurations can be constructed, we argue that…

Astrophysics · Physics 2009-02-20 Tsutomu Kobayashi , Kei-ichi Maeda

We consider stability of spherically symmetric solutions in $f(R)$ gravity model proposed by Starobinsky. We find that the model suffers from a severe fine tuning problem when applied to compact objects like neutron stars. The problem can…

General Relativity and Quantum Cosmology · Physics 2010-03-25 I. Thongkool , M. Sami , S. Rai Choudhury

Model of gravitational collapse of anisotropic compact stars in a new theory of $ f(R) $ gravity has been developed. The author considers the modified gravity model of $ f(R) = \xi R^4 $ to investigate a physically acceptable model of…

General Relativity and Quantum Cosmology · Physics 2022-04-01 Jay Solanki

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

This work is based on stability analysis of spherically symmetric collapsing star surrounding in locally anisotropic environment in $f(R,T)$ gravity, where $R$ is Ricci scalar and $T$ corresponds to the trace of energy momentum tensor.…

General Physics · Physics 2014-11-26 Ifra Noureen , M. Zubair

We study the structure of neutron stars in f(R) gravity theories with perturbative constraints. We derive the modified Tolman-Oppenheimer-Volkov equations and solve them for a polytropic equation of state. We investigate the resulting…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Alan Cooney , Simon DeDeo , Dimitrios Psaltis

In this work, we explore the eternal collapsing phenomenon of a stellar system (e.g., a star) within the framework of $f(R)$ gravity and investigate some new aspects of the continued homogeneous gravitational collapse with perfect fluid…

General Relativity and Quantum Cosmology · Physics 2023-11-30 Annu Jaiswal , Rajesh Kumar , Sudhir Kumar Srivastava , Megandhren Govender

This thesis aims at improving our understanding of the strong-field regime of gravity, where deviations from General Relativity (GR) are expected to be found on theoretical grounds. In particular, we have been concerned with the formulation…

General Relativity and Quantum Cosmology · Physics 2023-12-08 Adrián Casado-Turrión

The so-called Buchdahl limit is not yet fully understood in the context of theories of gravity beyond the Einsteinian framework. In this investigation, we generalize this limit for the case of static, spherically-symmetric, relativistic…

General Relativity and Quantum Cosmology · Physics 2025-04-14 Raul Carpio Fernandez , Alvaro de la Cruz-Dombriz

The gravitational dynamics of a collapsing matter configuration which is simultaneously radiating heat flux is studied in $f(R)$ gravity. Three particular functional forms in $f(R)$ gravity are considered to show that it is possible to…

General Relativity and Quantum Cosmology · Physics 2021-04-05 Ayan Chatterjee , Suresh C. Jaryal

In the present work we study non-rotating dark stars in $f(R)$ modified theory of gravity. In particular, we have considered bosonic self-interacting dark matter modelled inside the star as a Bose-Einstein condensate, while as far as the…

General Relativity and Quantum Cosmology · Physics 2018-02-14 Grigoris Panotopoulos , Ilidio Lopes

This paper aims to explore some realistic configurations of anisotropic spherical structures in the background of metric $f(R)$ gravity, where $R$ is the Ricci scalar. The solutions obtained by Krori and Barua are used to examine the nature…

General Relativity and Quantum Cosmology · Physics 2017-11-08 Z. Yousaf , M. Sharif , M. Ilyas , M. Z. Bhatti

Gravitational collapse is still poorly understood in the context of $f(R)$ theories of gravity, since the Oppenheimer-Snyder model is incompatible with their junction conditions. In this work, we will present a systematic approach to the…

General Relativity and Quantum Cosmology · Physics 2022-05-02 Adrián Casado-Turrión , Álvaro de la Cruz-Dombriz , Antonio Dobado

We consider stability properties of spherically symmetric spacetimes of stars in metric f(R) gravity. We stress that these not only depend on the particular model, but also on the specific physical configuration. Typically configurations…

General Relativity and Quantum Cosmology · Physics 2008-12-18 Kimmo Kainulainen , Daniel Sunhede

We study the structure of neutron stars in $f(R)=R+\alpha R^{2}$ theory of gravity (Starobinsky model), in an exact and non-perturbative approach. In this model, apart from the standard General Relativistic junction conditions, two extra…

General Relativity and Quantum Cosmology · Physics 2014-05-01 Apratim Ganguly , Radouane Gannouji , Rituparno Goswami , Subharthi Ray

We will make a comparison between the dynamics of spherical gravitational collapse for a perturbed FLRW universe to first order in the context of general relativity, with the corresponding results obtained for the gravitational collapse…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-12 César Peralta , Leonardo Castañeda

We address the problem of finding static and spherically symmetric anisotropic compact stars in general relativity that admit conformal motions. The study is framed in the language of f(R) gravity theory in order to expose opportunity for…

General Relativity and Quantum Cosmology · Physics 2017-07-06 Ayan Banerjee , Sumita Banerjee , Sudan Hansraj , Ali Ovgun

We study gravitational collapse for the Starobinsky $R^2$ model, a particular example of an $f(r)$ theory, in a spherically symmetric spacetime. We add a massless scalar field as matter content to the spacetime. We work in the Einstein…

General Relativity and Quantum Cosmology · Physics 2023-01-02 Yolbeiker Rodríguez Baez
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