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Related papers: On white dwarfs and neutron stars in Palatini f(R)…

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We study the interior spacetimes of stars in the Palatini formalism of f(R) gravity and derive a generalized Tolman-Oppenheimer-Volkoff and mass equation for a static, spherically symmetric star. We show that matching the interior solution…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Kimmo Kainulainen , Vappu Reijonen , Daniel Sunhede

Recent observations of several peculiar over- and under-luminous type Ia supernovae infer indirect evidence for the violation of the Chandrasekhar mass-limit by suggesting the existence of super- and sub-Chandrasekhar limiting mass white…

General Relativity and Quantum Cosmology · Physics 2022-01-11 Lupamudra Sarmah , Surajit Kalita , Aneta Wojnar

We investigate the Chandrasekhar mass limit for white dwarfs in various models of $f(R)$ gravity. Two equations of state for stellar matter are used: simple relativistic polytropic equation with polytropic index $n=3$ and the realistic…

General Relativity and Quantum Cosmology · Physics 2022-11-29 Artyom V. Astashenok , Sergey D. Odintsov , Vasilis Oikonomou

A few questions related to white dwarfs' physics is posed. It seems that the modified gravity framework can be a good starting point to provide alternative explanations to cooling processes, their age determination, and Chandrasekhar mass…

General Relativity and Quantum Cosmology · Physics 2021-07-29 Aneta Wojnar

A simple cooling model of white dwarf stars is re-analyzed in Palatini $f(R)$ gravity. Modified gravity affects the white dwarf structures and consequently their ages. We find that the resulting super-Chandrasekhar white dwarfs need more…

General Relativity and Quantum Cosmology · Physics 2022-12-06 Surajit Kalita , Lupamudra Sarmah , Aneta Wojnar

We examine the Chandrasekhar limit for white dwarfs in $f(R)$ gravity, with a simple polytropic equation of state describing stellar matter. We use the most popular $f(R)$ gravity model, namely the $f(R)=R+\alpha R^2$ gravity, and calculate…

General Relativity and Quantum Cosmology · Physics 2022-12-21 Artyom V. Astashenok , Sergey D. Odintsov , Vasilis K. Oikonomou

In this work we investigate the equilibrium configurations of white dwarfs in a modified gravity theory, na\-mely, $f(R,T)$ gravity, for which $R$ and $T$ stand for the Ricci scalar and trace of the energy-momentum tensor, respectively.…

General Relativity and Quantum Cosmology · Physics 2017-12-20 G. A. Carvalho , R. V. Lobato , P. H. R. S. Moraes , José D. V. Arbañil , R. M. Marinho , E. Otoniel , M. Malheiro

We study both analytically and numerically the gravitational fields of stars in f(R) gravity theories. We derive the generalized Tolman-Oppenheimer-Volkov equations for these theories and show that in metric f(R) models the Parameterized…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Kimmo Kainulainen , Johanna Piilonen , Vappu Reijonen , Daniel Sunhede

We work out the junction conditions for $f(R)$ gravity formulated in metric-affine (Palatini) spaces using a tensor distributional approach. These conditions are needed for building consistent models of gravitating bodies with an interior…

General Relativity and Quantum Cosmology · Physics 2020-10-28 Gonzalo J. Olmo , Diego Rubiera-Garcia

In this work, we investigate the relativistic structure of white dwarfs (WDs) within the framework of modified gravity theory $f(R, T, L_m) = R + \alpha T L_m$, which introduces a non-minimal coupling between matter and curvature. Using a…

General Relativity and Quantum Cosmology · Physics 2026-03-05 Edson Otoniel , Juan M. Z. Pretel , Clésio E. Mota , César O. V. Flores , Victor B. T. Alves , Franciele M. da Silva

In this work, we investigate the equilibrium configurations of massive white dwarfs (MWD) in the context of modified gravity, namely $f(R,L_m)$ gravity, where $R$ stands for the Ricci scalar and $L_m$ is the Lagrangian matter density. We…

General Relativity and Quantum Cosmology · Physics 2022-06-22 R. V. Lobato , G. A. Carvalho , N. G. Kelkar , M. Nowakowski

We consider static spherically symmetric stellar configurations in Palatini theories of gravity in which the Lagrangian is an unspecified function of the form $f(R,R_{\mu\nu}R^{\mu\nu})$. We obtain the Tolman-Oppenheimer-Volkov equations…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Gonzalo J. Olmo , Helios Sanchis-Alepuz , Swapnil Tripathi

General properties of neutron stars are briefly reviewed with an emphasis on the indispensability of general relativity in our understanding of these fascinating objects. In Newtonian gravity the pressure within a star merely plays the role…

High Energy Astrophysical Phenomena · Physics 2017-03-02 K. Yavuz Ekşi

It is agreed that Chandrasekhar mass and central density of white dwarfs are independent, which means that there is a whole series of stars having radius and central density as parameters that all have the same Chandrasekhar mass. In this…

General Physics · Physics 2016-08-09 Mohamed Moussa

The existence of possible massive white dwarfs more than the Chandrasekhar limit ($1.45M_{\odot }$, in which $M_{\odot }$ is mass of the sun) is a challenging topic. In this regard and motivated by the important effect of massive graviton…

General Relativity and Quantum Cosmology · Physics 2019-06-05 B. Eslam Panah , H. L. Liu

In the present work we study strange stars in $f(R)$ theories of gravity in the Palatini formalism. We consider two concrete well-known cases, namely the $R+R^2/(6 M^2)$ model as well as the $R-\mu^4/R$ model for two different values of the…

General Relativity and Quantum Cosmology · Physics 2017-05-03 Grigoris Panotopoulos

We investigate the hydrostatic equilibrium of white dwarfs within the framework of Rastall-Rainbow gravity, aiming to explore the effects of this modified gravitational theory on their properties. By employing the Chandrasekhar equation of…

General Relativity and Quantum Cosmology · Physics 2023-05-30 Jie Li , Bo Yang , Wenbin Lin

We investigate white dwarfs in the framework of f(R,L_m) and f(R,L_m,T) gravity to explore the Chandrasekhar Limit. We have considered two functional forms of f(R,L_m) and one functional form of f(R,L_m,T) gravity. Considering the matter…

General Relativity and Quantum Cosmology · Physics 2026-02-20 N. Priyobarta , S. K. Maurya , Ksh. Newton Singh , B. Mishra

In recent years, the idea of sub- and super-Chandrasekhar limiting mass white dwarfs (WDs), which are potential candidates to produce under- and over-luminous type Ia supernovae, respectively, has been a key interest in the scientific…

General Relativity and Quantum Cosmology · Physics 2022-02-04 Surajit Kalita , Lupamudra Sarmah

Modified gravity, known as $f(R)$ gravity, has presently been applied to Cosmology as a realistic alternative to dark energy. For this kind of gravity the expansion of the Universe may accelerate while containing only baryonic and cold dark…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-01 N. Pires , J. Santos , J. S. Alcaniz
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