Relativistic stars in mass-varying massive gravity

Sun, Xue F.; Zhou, Shuang-Yong

doi:10.1103/physrevd.101.044060

Cited by 8 publications

(8 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Yet another generalization of massive gravity is the so-called mass-varying massive gravity, where the mass of the graviton varies depending on the value of the scalar field [305]. Neutron stars in this model were studied by Sun and Zhou [160] using analytic fits of APR and SLy EOS. It is found that, depending on the value of the mass, m, appearing on a simple quartic potential, the maximum mass in both EOS can significantly increase by a factor ∼ 10% − 20% (with negligible modifications in the corresponding radius), though whether the parameters chosen are observationally viable is not discussed.…”

Section: Massive Gravitymentioning

confidence: 99%

See 1 more Smart Citation

Stellar structure models in modified theories of gravity: Lessons and challenges

2020

View full text Add to dashboard Cite

The understanding of stellar structure represents the crossroads of our theories of the nuclear force and the gravitational interaction under the most extreme conditions observably accessible. It provides a powerful probe of General Relativity on its strong field regime, and opens fruitful avenues for the exploration of new gravitational physics. The latter can be captured via the so-called modified theories of gravity, which modify the Einstein-Hilbert action of General Relativity and/or some of its building blocks/principles. These theories typically change the Tolman-Oppenheimer-Volkoff equations of stellar's hydrostatic equilibrium, having a large impact on the astrophysical properties of the corresponding stars, and thus opening a new window to constrain these theories with present and future observations of different types of stars. For relativistic stars, such as neutron stars, the uncertainty on the equation of state of matter at supranuclear densities intertwines with the new parameters coming from the modified gravity side, providing a whole new phenomenology for the typical predictions of stellar structure models, such as mass-radius relations, maximum masses, or moment of inertia. For non-relativistic stars, such as white, brown and red dwarfs, the weakening/strengthening of the gravitational force inside astrophysical bodies via the modified Newtonian (Poisson) equation may induce changes on the star's mass, radius, central density or luminosity, having an impact, for instance, in the Chandrasekhar's limit for white dwarfs, or in the minimum mass for stable hydrogen burning for high-mass brown dwarfs. This work aims to provide a broad overview of the main such results achieved in the recent literature for many such modified theories of gravity, by combining the results and constraints obtained from the analysis of relativistic and non-relativistic stars in different scenarios. Moreover, we will build a bridge between the efforts of the community working on different theories, formulations, types of stars, theoretical modellings, and observational aspects, highlighting some of the most promising opportunities in the field.

show abstract

Section: Massive Gravitymentioning

confidence: 99%

“…Super-Chandrasekhar white dwarfs have been also investigated within some extensions of massive gravity[160] and in non-commutative geometries[161], finding a theoretical maximum limit of 2.9M ⊙ in the former, and 2.6M ⊙ in the latter.…”

mentioning

confidence: 99%

Stellar structure models in modified theories of gravity: Lessons and challenges

2020

View full text Add to dashboard Cite

show abstract

“…As one can see, the highly expected breaking of spherical symmetry and the absence of strong magnetic fields in isolated white dwarfs, leads to an open window for other mechanisms that could also violate the Chandrasekhar limit. One such mechanism would be modified gravity [29][30][31][32][33][34][35][36][37][38][39][40]68]. In Ref.…”

Section: Massive White Dwarfs On the Grounds Of Modified Gravitymentioning

confidence: 99%

“…In this context, plenty of works have been done to model these very massive white dwarfs (MWD). The properties of MWDs have been studied in different contexts: rotation [7][8][9][10]; high electric and magnetic fields [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]; temperature [27,28] and modified gravity [29][30][31][32][33][34][35][36][37][38][39][40]. It has been shown that general relativistic effects are essential for massive white dwarfs and cannot a e-mail: r.vieira@uniandes.edu.co b e-mail: araujogc@ita.br c e-mail: nkelkar@uniandes.edu.co d e-mail: mnowakos@uniandes.edu.co (corresponding author) be disregarded [41][42][43][44][45].…”

Section: Introductionmentioning

confidence: 99%

Massive white dwarfs in $$f(\mathtt {R,L_m})$$ gravity

et al. 2022

View full text Add to dashboard Cite

In this work, we investigate the equilibrium configurations of massive white dwarfs (MWD) in the context of modified gravity, namely $$f(\mathtt {R,L_m})$$ f ( R , L m ) gravity, where $$\mathtt {R}$$ R stands for the Ricci scalar and $$\mathtt {L_m}$$ L m is the Lagrangian matter density. We focused on the specific case $$f(\mathtt {R,L_m})= \mathtt {R}/2 + \mathtt {L_m}+ \sigma \mathtt {R}\mathtt {L_m}$$ f ( R , L m ) = R / 2 + L m + σ R L m , i.e., we have considered a non-minimal coupling between the gravity field and the matter field, with $$\sigma $$ σ being the coupling constant. For the first time, the theory is applied to white dwarfs, in particular to study massive white dwarfs, which is a topic of great interest in the last years. The equilibrium configurations predict maximum masses which are above the Chandrasekhar mass limit. The most important effect of the theory is to increase significantly the mass for stars with radius < 2000 km. We found that the theory can accommodate the super-Chandrasekhar white dwarfs for different star compositions. Apart from this, the theory recovers the General Relativity results for stars with radii larger than 3000 km, independent of the value of $$\sigma $$ σ .

show abstract

“…In this context, plenty of works have been done to model these very massive white dwarfs (MWD). The properties of MWDs have been studied in different contexts: rotation [7-10]; high electric and magnetic fields [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]; temperature [27,28] and modified gravity [29][30][31][32][33][34][35][36][37][38][39][40]. It has been shown that general relativistic effects are essential for massive white dwarfs…”

mentioning

confidence: 99%

Massive white dwarfs in $f(R,L_m)$ gravity

Lobato,

Carvalho,

Kelkar

et al. 2022

Preprint

View full text Add to dashboard Cite

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 focused on the specific case f (R, L m ) = R/2 + L m + σ RL m , i.e., we have considered a non-minimal coupling between the gravity field and the matter field, with σ being the coupling constant. For the first time, the theory is applied to white dwarfs, in particular to study massive white dwarfs, which is a topic of great interest in the last years. The equilibrium configurations predict maximum masses which are above the Chandrasekhar mass limit. The most important effect of the theory is to increase significantly the mass for stars with radius < 2000 km. We found that the theory can accommodate the super-Chandrasekhar white dwarfs for different star compositions. Apart from this, the theory recovers the General Relativity results for stars with radii larger than 3000 km, independent of the value of σ . IntroductionRecently, the possibility of some white dwarfs (WD) surpassing the Chandrasekhar mass limit was raised [1-6]. The possible progenitor of such massive stars (M > 2M ) are being termed super-Chandrasekhar white dwarfs. In this context, plenty of works have been done to model these very massive white dwarfs (MWD). The properties of MWDs have been studied in different contexts: rotation [7-10]; high electric and magnetic fields [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]; temperature [27,28] and modified gravity [29][30][31][32][33][34][35][36][37][38][39][40]. It has been shown that general relativistic effects are essential for massive white dwarfs

show abstract

Relativistic stars in mass-varying massive gravity

Cited by 8 publications

References 38 publications

Stellar structure models in modified theories of gravity: Lessons and challenges

Stellar structure models in modified theories of gravity: Lessons and challenges

Massive white dwarfs in $$f(\mathtt {R,L_m})$$ gravity

Massive white dwarfs in $f(R,L_m)$ gravity

Contact Info

Product

Resources

About