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Related papers: Compact stars in the Einstein dark energy model

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Recently, observations of compact stars have provided new data of high accuracy which put strong constraints on the high-density behaviour of the equation of state of strongly interacting matter otherwise not accessible in terrestrial…

Nuclear Theory · Physics 2008-11-26 D. Blaschke , T. Klahn , F. Sandin

We analyse the Einstein-Cartan gravity in its standard form cal-R = R + cal-K^2, where cal-R and R are the Ricci scalar curvatures in the Einstein-Cartan and Einstein gravity, respectively, and cal-K^2 is the quadratic contribution of…

General Relativity and Quantum Cosmology · Physics 2016-11-04 A. N. Ivanov , M. Wellenzohn

Recent studies have shown that dark matter halos can support regular black holes or compact stars by assuming an anisotropic energy-momentum tensor. In this paper, we extend the analysis to the dark matter halo as an isotropic perfect…

General Relativity and Quantum Cosmology · Physics 2026-01-30 Yuan Yue , Yong-Qiang Wang

We obtain well behaved interior solutions describing hydrostatic equilibrium of anisotropic relativistic stars in scale-dependent gravity, where Newton's constant is allowed to vary with the radial coordinate throughout the star. Assuming…

General Relativity and Quantum Cosmology · Physics 2021-01-26 Grigoris Panotopoulos , Angel Rincon , Ilidio Lopes

Gravitational waves from merging compact objects provides the opportunity to explore the properties of black holes and neutron stars in the strong regime of gravity. It is therefore of interest to explore the theoretical model that…

High Energy Physics - Theory · Physics 2023-01-24 Irvin Martinez

The possibility of strange stars mixed with dark energy to be one of the candidates for dark energy stars is the main issue of the present study. Our investigation shows that quark matter acts as dark energy after a certain yet unknown…

General Relativity and Quantum Cosmology · Physics 2021-11-15 Theophanes Grammenos , Farook Rahamn , Saibal Ray , Debabrata Deb , Sourav Roy Chowdhury

Two distinct non-singular interior models that describe anisotropic spherical configurations are presented in this work. We develop the Einstein field equations and the associated mass function in accordance with a static spherical…

General Relativity and Quantum Cosmology · Physics 2025-10-10 M. Sharif , Tayyab Naseer , Hira Shadab

Studying the physics of compact objects in modified theories of gravity is important for understanding how future observations can test alternatives to General Relativity. We consider a subset of vector-tensor Galileon theories of gravity…

High Energy Physics - Theory · Physics 2018-02-14 Javier Chagoya , Gianmassimo Tasinato

We consider a general class of vector-tensor theories of gravity and show that solutions with accelerated expansion and a future type III singularity are a common feature in these models. We also show that there are only six vector-tensor…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Jose Beltran Jimenez , Antonio L. Maroto

We consider the general situation of a compact relativistic body with anisotropic pressures in the presence of the electromagnetic field. The equation of state for the matter distribution is linear and may be applied to strange stars with…

General Relativity and Quantum Cosmology · Physics 2009-01-16 S. Thirukkanesh , S. D. Maharaj

We constrain the nuclear matter equation of state within the relativistic mean field model by including the isoscalar-vector and isovector-vector coupling term at a fundamental level using the Bayesian analysis. We used the nuclear…

Nuclear Theory · Physics 2025-05-06 Deepak Kumar , Pradip Kumar Sahu

A simple generalization to Einstein's general relativity (GR) was recently proposed which allows a correction term $T_{\alpha\beta}T^{\alpha\beta}$ in the action functional of the theory. This theory is called Energy-Momentum Squared…

General Relativity and Quantum Cosmology · Physics 2018-07-25 Nasrin Nari , Mahmood Roshan

In the present paper we have constructed a new relativistic anisotropic compact star model having a spherically symmetric metric of embedding class one. Here we have assumed an arbitrary form of metric function and solved the Einstein…

General Relativity and Quantum Cosmology · Physics 2017-07-26 Piyali Bhar , Ksh. Newton Singh , Tuhina Manna

Einstein's theory of general relativity predicts that the only stationary configuration of an isolated black hole is the Kerr spacetime, which has a unique multipolar structure and a spherical shape when non-spinning. This is in striking…

General Relativity and Quantum Cosmology · Physics 2020-09-02 Guilherme Raposo , Paolo Pani

Physics invites the idea that space contains energy whose gravitational effect approximates that of Einstein's cosmological constant, Lambda; nowadays the concept is termed dark energy or quintessence. Physics also suggests the dark energy…

Astrophysics · Physics 2008-11-26 P. J. E. Peebles , Bharat Ratra

Modified theories of gravity that offer viable models for dark energy often rely on mechanisms that screen their effects in high density environments. From this perspective, it would appear that, once solar system constraints are satisfied,…

General Relativity and Quantum Cosmology · Physics 2020-07-24 Bernardo F. de Aguiar , Raissa F. P. Mendes

The hypernuclear matter is studied within the relativistic Hartree-Fock theory employing several parametrizations of the hypernuclear density functional with density-dependent couplings. The equations of state and compositions of…

Nuclear Theory · Physics 2018-08-16 Jia Jie Li , Wen Hui Long , Armen Sedrakian

In our recently proposed quantum theory of gravity, the universe is made of `atoms' of space-time-matter (STM). Planck scale foam is composed of STM atoms with Planck length as their associated Compton wave-length. The quantum dispersion…

General Relativity and Quantum Cosmology · Physics 2020-08-03 Tejinder P. Singh

In the present work we use the vector MIT bag model to describe quark matter and obtain the macroscopic properties of neutron stars. We also calculate the speed of sound of quark matter described by this model with specific parameter values…

Nuclear Theory · Physics 2023-05-22 Maíra Cesário Alvim Lobo , Débora Peres Menezes

High massive compact stars have been reported recently in the literature, providing strong constraints on the properties of the ultradense matter beyond the saturation nuclear density. In view of these results, the calculations of quark…

High Energy Astrophysical Phenomena · Physics 2014-07-18 Hilario Rodrigues , Sergio B. Duarte , Jos Carlos T. de Oliveira