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Related papers: White dwarf stars in modified gravity

200 papers

We analyze the effects of modified gravity on specific heats of electrons and ions, Debye temperature, crystallization process, and cooling mechanism in white dwarfs. We derive the Lane-Emden-Chandrasekhar equation and relate it to the…

General Relativity and Quantum Cosmology · Physics 2023-03-07 Surajit Kalita , Lupamudra Sarmah , 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 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

Super-Chandrasekhar white dwarfs are a timely topic in the last years in the scientific community due to its connection to supernovae type Ia (SN Ia). Some early studies tackled the possibility of white dwarfs surpassing the Chandrasekhar…

General Relativity and Quantum Cosmology · Physics 2025-10-20 Ronaldo V. Lobato , Geanderson A. Carvalho , Neelima G. Kelkar , Marek Nowakowski

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

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 clarify important physics issues related to the recently established new mass limit for magnetized white dwarfs which is significantly super-Chandrasekhar. The issues include, justification of high magnetic field and the corresponding…

Solar and Stellar Astrophysics · Physics 2014-06-05 Upasana Das , Banibrata Mukhopadhyay

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

Is the Chandrasekhar mass limit for white dwarfs (WDs) set in stone? Not anymore -- recent observations of over-luminous, peculiar type Ia supernovae can be explained if significantly super-Chandrasekhar WDs exist as their progenitors, thus…

High Energy Astrophysical Phenomena · Physics 2013-09-19 Upasana Das , Banibrata Mukhopadhyay

There are currently two open questions in white dwarf physics: why are massive dwarfs observed less often in astronomical surveys, and why have not any super-Chandrasekhar white dwarfs been found despite the discovery of more than a dozen…

Solar and Stellar Astrophysics · Physics 2024-02-13 Aneta Wojnar , Surajit Kalita , Lupamudra Sarmah

Scalar-tensor theories of gravity can lead to modifications of the gravitational force inside astrophysical objects. We exhibit that compact stars such as white dwarfs provide a unique set-up to test beyond Horndeski theories of ${\rm G}^3$…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-20 Rajeev Kumar Jain , Chris Kouvaris , Niklas Grønlund Nielsen

While computing the Fermi degeneracy pressure of electrons in a white dwarf star within the framework of hydrostatic equilibrium, we depart from the extant practice of treating the electrons as a free fermion gas, by including the effect of…

General Relativity and Quantum Cosmology · Physics 2017-08-22 Anarya Ray , Pronobesh Maity , Parthasarathi Majumdar

The idea of possible modification to gravity theory, whether it is in the Newtonian or general relativistic premises, is there for quite sometime. Based on it, astrophysical and cosmological problems are targeted to solve. But none of the…

General Relativity and Quantum Cosmology · Physics 2022-01-02 Agrim Sharma , Banibrata Mukhopadhyay

Modified gravity theories can introduce modifications to the Poisson equation in the Newtonian limit. As a result, we expect to see interesting features of these modifications inside stellar objects. White dwarf stars are one of the most…

General Relativity and Quantum Cosmology · Physics 2017-10-06 Srimanta Banerjee , Swapnil Shankar , Tejinder P. Singh

In Palatini $f(R)$ gravity, the parameters of the Schwarzschild - de Sitter solution as well as the whole interior solutions of compact objects are expected to change when compared to general relativity. We solve the Palatini field…

General Relativity and Quantum Cosmology · Physics 2009-12-07 Vappu Reijonen

We study the effects of massive scalar-tensor theories on the internal properties, crystallization, and cooling process of white dwarf stars that might potentially solve observational tensions. We show that these modified gravity theories…

General Relativity and Quantum Cosmology · Physics 2024-08-29 Sofía Vidal , Aneta Wojnar , Laur Järv , Daniela Doneva

The proper quantum plasma treatment of the electron gas in degenerate stars such as white dwarfs provides an additional quantum contribution to the electron pressure. The additional pressure term modifies the equation for hydrostatic…

Solar and Stellar Astrophysics · Physics 2012-04-20 Reinhard Schlickeiser , Ian Lerche , Christian Röken

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

After the prediction of many sub- and super-Chandrasekhar (at least a dozen for the latter) limiting mass white dwarfs, hence apparently peculiar class of white dwarfs, from the observations of luminosity of type Ia supernovae, researchers…

High Energy Astrophysical Phenomena · Physics 2021-03-09 Surajit Kalita , Banibrata Mukhopadhyay

Since 2012, we have initiated a new idea showing that the mass of highly magnetized or modified Einstein's gravity induced white dwarfs could be significantly super-Chandrasekhar with a different mass-limit. This discovery has several…

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