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Related papers: White dwarf stars in modified gravity

200 papers

In the light of the recent and unexpected discovery of a brand new type of white dwarfs, those with carbon-dominated atmospheres, we examine the asteroseismological potential of such stars. The motivation behind this is based on the…

Astrophysics · Physics 2009-11-13 G. Fontaine , P. Brassard , P. Dufour

We systematically assess several limiting cases of modified gravity, where particular theoretical or observational conditions hold. This framework includes the well known scalar-tensor gravity and No Slip Gravity and No Run Gravity, and we…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-15 Eric V. Linder

Low mass white dwarfs are the remnants of disrupted red giant stars in binary millisecond pulsars and other exotic binary star systems. Some low mass white dwarfs cool rapidly, while others stay bright for millions of years due to stable…

We investigate the properties of anisotropic white dwarf stars within the rainbow gravity adopting for matter content the Chandrasekhar model based on an ideal Fermi gas at zero temperature. We study in detail the effects of the anisotropic…

General Relativity and Quantum Cosmology · Physics 2024-11-20 Takol Tangphati , Grigoris Panotopoulos , Ayan Banerjee , Anirudh Pradhan

It was previously argued that generalized uncertainty principle (GUP) with a positive parameter removes the Chandrasekhar limit. One way to restore the limit is by taking the GUP parameter to be negative. In this work we discuss an…

General Relativity and Quantum Cosmology · Physics 2019-01-02 Yen Chin Ong , Yuan Yao

Recently, several white dwarfs have been proposed with masses significantly above the Chandrasekhar limit, known as Super-Chandrasekhar White Dwarfs, to account for the overluminous Type Ia supernovae. In the present work, Equation of State…

Solar and Stellar Astrophysics · Physics 2017-03-16 Somnath Mukhopadhyay , Debasis Atta , D. N. Basu

Fluid and ultralight bosonic dark matter can interact through gravity to form stable fermion-boson stars, which are static and regular mixed solutions of the Einstein-Euler-(complex, massive) Klein-Gordon system. In this work we study the…

General Relativity and Quantum Cosmology · Physics 2022-04-27 Nicolas Sanchis-Gual , Paula Izquierdo

Interior structures of stellar objects might have small pressure anisotropy due to several reasons, including rotation and the presence of magnetic fields. Here, retaining the approximation of spherical symmetry, we study the possible role…

Solar and Stellar Astrophysics · Physics 2019-11-06 Shaswata Chowdhury , Tapobrata Sarkar

We present an analysis of the close double degenerate NLTT 12758, which is comprised of a magnetic white dwarf with a field of about 3.1 MG and an apparently non-magnetic white dwarf. We measured an orbital period of 1.154 days and found…

Solar and Stellar Astrophysics · Physics 2017-01-18 Adela Kawka , Gordon P. Briggs , Stephane Vennes , Lilia Ferrario , Ernst Paunzen , Dayal T. Wickramasinghe

The non-equivalence between the metric and Palatini formalisms of $f(R)$ gravity is an intriguing feature of these theories. However, in the recently proposed hybrid metric-Palatini gravity, consisting of the superposition of the metric…

General Relativity and Quantum Cosmology · Physics 2013-08-23 Salvatore Capozziello , Tiberiu Harko , Francisco S. N. Lobo , Gonzalo J. Olmo

While the accretion power in astrophysics has been studied in many astronomical environments, the ``spin--down power'' is often neglected. In this essay I demonstrate that the spin--down power alone may drive a rotating system from…

Astrophysics · Physics 2021-10-20 Feng Ma

The distinction between modified gravity and quintessence or dynamical dark energy is difficult. Many models of modified gravity are equivalent to models of coupled quintessence by virtue of variable transformations. This makes an…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 C. Wetterich

The properties of uniformly rotating white dwarfs (RWDs) are analyzed within the framework of Newton's gravity and general relativity. In both cases Hartle's formalism is applied to construct the internal and external solutions to the field…

Solar and Stellar Astrophysics · Physics 2015-03-16 Kuantay Boshkayev , Jorge A. Rueda , Remo Ruffini , Ivan Siutsou

White dwarfs rotate. The angular momentum in single white dwarfs must originate early in the life of the star, but also must be modified (and perhaps severely modified) during the many stages of evolution between birth as a main--sequence…

Astrophysics · Physics 2007-05-23 Steven D. Kawaler

A modified Newton's gravity is obtained as the weak field approximation of the Einstein's equation in Finsler space. It is found that a specified Finsler structure makes the modified Newton's gravity equivalent to the modified Newtonian…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Zhe Chang , Xin Li

Precession is observed routinely in solid bodies of Solar system and it has been invoked to explain number of phenomena observed in pulsars (i.e. Link 2003, Breton et al. 2008). White dwarfs also have been considered as possible candidates…

Solar and Stellar Astrophysics · Physics 2011-11-11 G. Tovmassian , S. Zharikov , V. Neustroev

In modified gravity theories that seek to explain cosmic acceleration, dwarf galaxies in low density environments can be subject to enhanced forces. The class of scalar-tensor theories, which includes f(R) gravity, predict such a force…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Bhuvnesh Jain , Jake Vanderplas

This paper addresses the effect of generalized uncertainty principle, emerged by a different approaches of quantum gravity within Planck scale, on thermodynamic properties of photon, non-relativistic ideal gases and degenerate fermions. A…

General Physics · Physics 2015-12-15 Mohamed Moussa

We show that the upper bound for the central magnetic field of a super-Chandrasekhar white dwarf calculated by Nityananda and Konar [Phys. Rev. D 89, 103017 (2014)] is completely erroneous. This in turn strengthens the argument in favor of…

Solar and Stellar Astrophysics · Physics 2014-06-09 Upasana Das , Banibrata Mukhopadhyay

This is a concise review, addressed to undergraduate students, of S. Chandrasekhar's oeuvre in astrophysics, ranging from his early studies on white dwarfs using relativistic quantum statistics to topics as diverse as dynamical friction,…

History and Philosophy of Physics · Physics 2012-02-28 Patrick Das Gupta