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

200 papers

We study the gravitational collapse in modified gravitational theories. In particular, we analyze a general $f(R)$ model with uniformly collapsing cloud of self-gravitating dust particles. This analysis shares analogies with the formation…

General Relativity and Quantum Cosmology · Physics 2015-06-03 J. A. R. Cembranos , A. de la Cruz-Dombriz , B. Montes Nuñez

We discuss the stability and construct dynamical configurations describing the gravitational collapse of unstable neutron stars with realistic equations of state compatible with the recent LIGO-Virgo constraints. Unlike other works that…

General Relativity and Quantum Cosmology · Physics 2020-06-17 J. M. Z. Pretel , M. F. A. da Silva

In this paper we work out collapsing conditions for a spherical star in the weak field limit of the $R+\mu^4/R$ gravity and discuss the importance of the parameter $\mu$ to generate different criteria in the theory. Such criteria are proved…

General Relativity and Quantum Cosmology · Physics 2016-10-19 Mohsen Fathi , Morteza Mohseni

We reconcile seemingly conflicting statements in the literature about the behavior of cosmological solutions in modified theories of gravity where the Einstein-Hilbert Lagrangian for gravity is modified by the addition of a function of the…

Astrophysics · Physics 2008-11-26 Ignacy Sawicki , Wayne Hu

We provide a set of exact spherically symmetric solutions describing the interior of a relativistic star under f(T) modified gravity. To tackle the problem with lucidity we also assume the existence of a conformal Killing vector field…

General Relativity and Quantum Cosmology · Physics 2015-07-20 Amit Das , Farook Rahaman , B. K. Guha , Saibal Ray

It is shown that the theoretical arguments for the unavoidable collapse of massive stars, which are valid within standard general relativity, are not valid in extended gravity. In particular a calculation is reported of neutron stars within…

General Relativity and Quantum Cosmology · Physics 2011-12-22 Emilio Santos

We study the gravitational collapse of a star with barotropic equation of state $p=w\rho$ in the context of $f({\mathcal R})$ theories of gravity. Utilizing the metric formalism, we rewrite the field equations as those of Brans-Dicke theory…

General Relativity and Quantum Cosmology · Physics 2015-05-28 A. H. Ziaie , K. Atazadeh , S. M. M. Rasouli

The gravitational collapse of a spherical distribution, in a class of f(R) theories of gravity, where f(R) is power function of R, is discussed. The spacetime is assumed to admit a homothetic Killing vector. In the collapsing modes, some of…

General Relativity and Quantum Cosmology · Physics 2016-07-28 Soumya Chakrabarti , Narayan Banerjee

We investigate various anisotropic spherical distributions of charged celestial bodies within the context of f(R) gravity, where R represents the Ricci scalar. The properties of specific charged compact objects are analyzed by using the…

General Relativity and Quantum Cosmology · Physics 2025-05-13 W. U. Rahman , M. Ilyas , Yi Zhong , De-Liang Yao

This paper is about the $n+2$-dimensional gravitational contraction of inhomogeneous fluid without heat flux in the framework of $f(R)$ metric theory of gravity. Matching conditions for two regions of a star has been derived by using the…

General Relativity and Quantum Cosmology · Physics 2017-08-02 G. Abbas , M. S. Khan , Zahid Ahmad , M. Zubair

We propose a form of gravity-matter interaction given by $\omega RT$ in the framework of $f(R,T)$ gravity and examine the effect of such interaction in spherically symmetric compact stars. Treating the gravity-matter coupling as a…

General Relativity and Quantum Cosmology · Physics 2020-07-14 Arun Mathew , Muhammed Shafeeque , Malay K. Nandy

The gravitational collapse of a star is a warmly discussed but still puzzling problem, which not only involves the dynamics of the gases, but also the subtle coordinate transformation. In this letter, we give some more detailed…

General Relativity and Quantum Cosmology · Physics 2009-04-30 Ying-Qiu Gu

We study relativistic stars in the context of scalar tensor theories of gravity that try to account for the observed cosmic acceleration and satisfy the local gravity constraints via the chameleon mechanism. More specifically, we consider…

General Relativity and Quantum Cosmology · Physics 2015-03-13 E. Babichev , D. Langlois

We analyze the stability of the Einstein static universe by considering homogeneous scalar perturbations in the context of f(R) modified theories of gravity. By considering specific forms of f(R), the stability regions of the solutions are…

General Relativity and Quantum Cosmology · Physics 2012-06-22 Christian G. Boehmer , Lukas Hollenstein , Francisco S. N. Lobo

We consider a modified gravity theory, $f(R)=R+\alpha R^n-\frac{\mu^4}{R^m}$, in the metric formulation and analyze the contribution of electromagnetic field on the range of dynamical instability of a star filled with anisotropic matter.…

General Physics · Physics 2015-10-22 H. Rizwana Kausar , Ifra Noureen , M. Umair Shahzad

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

In this paper we study an Oppenheimer-Snyder (OS)-like gravitational collapse in the general framework of scale-dependent gravity. We explore the collapse in spherically symmetric solutions suggested both by asymptotically safe gravity…

General Relativity and Quantum Cosmology · Physics 2025-04-07 Ramin Hassannejad , Gaetano Lambiase , Fabio Scardigli , Fatimah Shojai

We study the spherically symmetric gravitational collapse of massless scalar matter field in asymptotic flat spacetime in $f(R)$ gravity. In the Einstein frame of $f(R)$ gravity, an additional scalar field arises due to the conformal…

General Relativity and Quantum Cosmology · Physics 2016-11-15 Cheng-Yong Zhang , Zi-Yu Tang , Bin Wang

In this paper, we investigate spherically symmetric perfect fluid gravitational collapse in metric $f(R)$ gravity. We take non-static spherically symmetric metric in the interior region and static spherically symmetric metric in the…

General Relativity and Quantum Cosmology · Physics 2011-01-17 M. Sharif , H. Rizwana Kausar

We use 1-dimensional numerical simulations to study spherical collapse in the f(R) gravity models. We include the nonlinear coupling of the gravitational potential to the scalar field in the theory and use a relaxation scheme to follow the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Alex Borisov , Bhuvnesh Jain , Pengjie Zhang