English
Related papers

Related papers: Strange quark star in dilaton gravity

200 papers

The realistic models of neutron stars are considered for simple $R+\alpha R^2$ gravity and equivalent Brance-Dicke theory with dilaton field in Einsein frame. For negative values of $\alpha$ we have no acceptable results from astrophysical…

General Relativity and Quantum Cosmology · Physics 2018-12-27 Artyom V. Astashenok , Alexey S. Baigashov , Sergey A. Lapin

We study relativistic stars in the simplest model of the de Rham-Gabadadze-Tolley massive gravity which describes the massive graviton without ghost propagating mode. We consider the hydrostatic equilibrium, and obtain the modified…

General Relativity and Quantum Cosmology · Physics 2016-06-15 Taishi Katsuragawa , Shin'ichi Nojiri , Sergei D. Odintsov , Masashi Yamazaki

We systematically investigate the observable properties of dark matter-admixed quark stars (DQSs) using the confined-isospin-density-dependent-mass model in combination with the generic bosonic self-interacting dark matter model. Our…

Nuclear Theory · Physics 2025-01-09 Hong-Ming Liu , Peng-Cheng Chu , He Liu , Xiao-Hua Li , Zeng-Hua Li

The quasiparticle model is extended to investigate the properties of strange quark matter in a strong magnetic field at finite densities. For the density-dependent quark mass, self-consistent thermodynamic treatment is obtained with an…

High Energy Physics - Phenomenology · Physics 2012-08-08 Xin-Jian Wen , Shou-Zheng Su , Dong-Hong Yang , Guang-Xiong Peng

As a model for nonideal behavior in the equation of state of QCD at high density, we consider cold quark matter in perturbation theory. To second order in the strong coupling constant, $\alpha_s$, the results depend sensitively on the…

High Energy Physics - Phenomenology · Physics 2009-12-31 Eduardo S. Fraga , Robert D. Pisarski , Jurgen Schaffner-Bielich

We investigated the radial and non-radial fundamental ($f$) mode oscillations of self-bound (quark) stars obtained after employing the Vector MIT (vMIT) bag model. Within this model, we computed the equation of state for strange quark…

High Energy Physics - Phenomenology · Physics 2025-05-14 Luiz L. Lopes , Jose C. Jimenez , Luis B. Castro , Cesar V. Flores

In this paper, we investigate how the fine structure constant, $\alpha$, locally varies in the presence of a static and spherically symmetric gravitational source. The procedure consists in calculating the solution and the energy…

General Relativity and Quantum Cosmology · Physics 2016-09-27 V. B. Bezerra , M. S. Cunha , C. R. Muniz , M. O. Tahim , H. S. Vieira

The description of the heaviest neutron stars observed in Nature depends on the understanding of the physical concepts present in General Relativity and Quantum Chromodynamics. In this work, we review the basic concepts need to describe…

High Energy Physics - Phenomenology · Physics 2020-08-11 V. P. Goncalves , L. Lazzari

Loop Quantum Cosmology strongly modifies the high-energy dynamics of Friedman-Robertson-Walker models and removes the big-bang singularity. We investigate how LQC corrections affect the stability properties of the Einstein static universe.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Luca Parisi , Marco Bruni , Roy Maartens , Kevin Vandersloot

We investigate non-radial oscillations of hadronic, hybrid and pure self-bound strange quark stars with maximum masses above the mass of the recently observed massive pulsars PSR J1614-2230 and PSR J0348-0432 with $M \approx 2 M_{\odot}$.…

High Energy Astrophysical Phenomena · Physics 2017-09-01 C. V. Flores , G. Lugones

The LIGO/VIRGO detection of the gravitational waves from a binary merger system, GW170817, has put a clean and strong constraint on the tidal deformability of the merging objects. From this constraint, deep insights can be obtained in…

High Energy Astrophysical Phenomena · Physics 2018-05-02 Enping Zhou , Xia Zhou , Ang Li

We employ the MIT bag model with density-dependent bag constant for the equation of state (EOS) to estimate the gravitational mass and Keplerian frequency of rapidly rotating strange quark stars (SQS). In a companion paper we discuss the…

High Energy Astrophysical Phenomena · Physics 2026-01-15 Fatemeh Kayanikhoo , Mateusz Kapusta , Miljenko Čemeljić , Wlodek Kluzniak , Leszek Zdunik

We present the first numerical models of differentially rotating stars in alternative theories of gravity. We chose a particular class of scalar-tensor theories of gravity that is indistinguishable from GR in the weak field regime but can…

General Relativity and Quantum Cosmology · Physics 2018-12-05 Daniela D. Doneva , Stoytcho S. Yazadjiev , Nikolaos Stergioulas , Kostas D. Kokkotas

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 the strong…

General Relativity and Quantum Cosmology · Physics 2020-09-15 Gonzalo J. Olmo , Diego Rubiera-Garcia , Aneta Wojnar

We study the static cosmological solutions and their stability at background level in the framework of massive bigravity theory with Friedmann-Robertson-Walker (FRW) metrics. By the modification proposed in the cosmological equations…

General Relativity and Quantum Cosmology · Physics 2017-05-17 M. Mousavi , F. Darabi

In this paper, we investigated the thermodynamic properties of strange quark matter using Nambu-Jona-Lasinio (NJL) model at finite temperatures where we considered the dynamical mass as the effective interaction between quarks. By…

Nuclear Theory · Physics 2019-05-22 G. H. Bordbar , R. Hosseini , F. Kayanikhoo , A. Poostforush

This paper investigates how a self bound equation of state (EOS), which describes strange quark stars, affects the rotational properties of compact stars, focusing on deviations from universal relations governing gravitational mass and…

High Energy Astrophysical Phenomena · Physics 2025-12-16 Andreas Konstantinou

We study equilibrium configurations of boson stars in the framework of a class scalar-tensor theories of gravity with massive gravitational scalar (dilaton). In particular we investigate the influence of the mass of the dilaton on the boson…

General Relativity and Quantum Cosmology · Physics 2009-10-31 P. Fiziev , S. Yazadjiev , T. Boyadjiev , M. Todorov

At finite temperature (T) there is a link with general relativity and hydrodynamics that leads to a lower bound for the ratio of shear viscosity and entropy density (\eta/s). We find that the bound is saturated in the simple model for quark…

High Energy Physics - Phenomenology · Physics 2007-06-13 Sibasish Laha , Taparati Gangopadhyay , Manjari Bagchi , Mira Dey , Jishnu Dey , Monika Sinha , Subharthi Ray

One of the few firm predictions of string theory is the existence of a massless scalar field coupled to gravity, the dilaton. In its presence, the value of the fundamental constants of the universe, such as the fine-structure constant, will…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-03 Léo Vacher , Nils Schöneberg , J. D. F. Dias , C. J. A. P. Martins , Francisco Pimenta