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Related papers: Compact objects in modified gravity: junction cond…

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We discuss the global properties of static, spherically symmetric configurations of a self-gravitating real scalar field $\phi$ in general relativity (GR), scalar-tensor theories (STT) and high-order gravity ($L=f(R)$) in various…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Kirill A. Bronnikov

Although $f(R)$ modified gravity models can be made to satisfy solar system and cosmological constraints, it has been shown that they have the serious drawback of the nonexistence of stars with strong gravitational fields. In this paper, we…

Astrophysics · Physics 2009-01-21 Tsutomu Kobayashi , Kei-ichi Maeda

The recent theoretical advance known as the Minimal Geometric Deformation (MGD) method has initiated a renewed interest in investigating higher curvature gravitational effects in relativistic astrophysics. In this work, we model a strange…

General Relativity and Quantum Cosmology · Physics 2022-02-16 S. K. Maurya , Ksh. Newton Singh , M. Govender , Sudan Hansraj

Present paper deals with the composition and modelling of compact dense astrophysical bodies under the framework of $f(R)$ gravity. The model is employed on various observed strange stars viz., SMC X-1, SAX J1808.4-3658, Swift J1818.0-1607,…

General Relativity and Quantum Cosmology · Physics 2020-08-12 B. Thakore , R. Goti , S. Shah , H. Pandya , D. M. Pandya

In this paper, we explore the existence of various non-singular compact stellar solutions influenced by the Maxwell field within the matter-geometry coupling based modified gravity. We start this analysis by considering a static spherically…

General Relativity and Quantum Cosmology · Physics 2024-09-04 Tayyab Naseer , Jackson Levi Said

Viable corrections to the matter sector of Poisson's equation may result in qualitatively different astrophysical phenomenology, for example the gravitational collapse and the properties of compact objects can change drastically. We discuss…

General Relativity and Quantum Cosmology · Physics 2013-05-30 Paolo Pani , Terence Delsate , Vitor Cardoso

In recent literature, it has been argued that a mild form of the Weak Gravity Conjecture (WGC) is satisfied by wide classes of effective field theories in which higher-derivative corrections can be shown to shift the charge-to-mass ratios…

High Energy Physics - Theory · Physics 2019-09-06 Lars Aalsma , Alex Cole , Gary Shiu

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

We examine the effects of $f(R)$ gravity on Jeans analysis of collapsing dust clouds. We provide a method for testing modified gravity models by their effects on star formation as the presence of $f(R)$ gravity is found to modify the limit…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-06 Jaakko Vainio , Iiro Vilja

In this manuscript, we provide a comprehensive study of gravitational lensing by dark compact objects predicted by a Modified Gravity (MOG) based on the Scalar-Vector-Tensor action, and the aim is to analyze new insights into the nature of…

General Relativity and Quantum Cosmology · Physics 2025-03-07 Nagina Rehman , Zoe C. S. Chan , Mubasher Jamil , Mustapha Azreg-Aïnou

We review recent developments and results in testing general relativity (GR) at cosmological scales. The subject has witnessed rapid growth during the last two decades with the aim of addressing the question of cosmic acceleration and the…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-09 Mustapha Ishak

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

We perform a dynamical system analysis of Myrzakulov or F(R, T) gravity, which is a subclass of affinely connected metric theories, where ones uses a specific but non-special connection, which allows for non-zero curvature and torsion…

General Relativity and Quantum Cosmology · Physics 2022-11-30 G. Papagiannopoulos , Spyros Basilakos , Emmanuel N. Saridakis

Emergent modified gravity is a canonical theory based on general covariance where the spacetime is not fundamental, but rather an emergent object. This feature allows for modifications of the classical theory and can be used to model new…

General Relativity and Quantum Cosmology · Physics 2024-02-06 Erick I. Duque

Recently a new -quantum motivated- theory of gravity has been proposed that modifies the standard Newtonian potential at large distances when spherical symmetry is considered. Accordingly, Newtonian gravity is altered by adding an extra…

Astrophysics of Galaxies · Physics 2013-03-14 Jorge Mastache , Jorge L. Cervantes-Cota , Axel de la Macorra

Motivated by string/M-theory predictions that scalar field couplings with the Gauss-Bonnet invariant, G, are essential in the appearance of non-singular early time cosmologies, we discuss the viability of an interesting alternative…

General Relativity and Quantum Cosmology · Physics 2015-03-17 Nadiezhda Montelongo García , Tiberiu Harko , Francisco S. N. Lobo , José P. Mimoso

Critical phenomena in gravitational collapse opened a new mathematical vista into the theory of general relativity and may ultimately entail fundamental physical implication in observations. However, at present, the dynamics of critical…

General Relativity and Quantum Cosmology · Physics 2010-01-12 Mew-Bing Wan

Motivation: Motivated by the growing interest in understanding the role of non-metricity in describing dense stellar systems, in this paper, we study compact stellar configurations within the framework of linear $f(Q)$ gravity. Methodology:…

General Relativity and Quantum Cosmology · Physics 2026-04-28 Arpita Ghosh , Abhishek Paul , Ranjan Sharma , Samstuti Chanda

We consider the gravitational collapse of a spherically symmetric ball of dust in the general relativistic weak gravity regime. The velocity of the matter as viewed by external observers is compared to the velocity gauged by local…

Astrophysics · Physics 2008-11-26 F. I. Cooperstock , S. Tieu

We model a compact radiant star that undergoes gravitational collapse from a certain initial static configuration until it becomes a black hole. The star consists of a fluid with anisotropy in pressures, bulk viscosity, in addition to the…

General Relativity and Quantum Cosmology · Physics 2023-04-26 A. C. Mesquita , M. F. A. da Silva