English
Related papers

Related papers: A three-layer preon star model from exact piecewis…

200 papers

In the context of the standard model of particle physics, there is a definite upper limit to the density of stable compact stars. However, if a more fundamental level of elementary particles exists, in the form of preons, stability may be…

Astrophysics · Physics 2007-05-23 J. Hansson , F. Sandin

A formulation of Einstein equations is presented that could yield advantages in the study of collisions of binary compact objects during regimes between linear-nonlinear transitions. The key idea behind this formulation is a separation of…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Pablo Laguna

We discuss numerical solutions of Einstein's field equation describing static, spherically symmetric conglomerations of a photon gas. These equations imply a back reaction of the metric on the energy density of the photon gas according to…

General Relativity and Quantum Cosmology · Physics 2015-06-25 H. -J. Schmidt , F. Homann

Hybrid star is the term given to a neutron star with a quark core. Due to a lot of uncertainties in the calculations and compositions of such a high-density system, it is of great interest and a preferred scenario for particle physicists…

General Relativity and Quantum Cosmology · Physics 2023-12-14 Akashdip Karmakar , Pramit Rej

In this present work, we have obtained a singularity-free spherically symmetric stellar model with anisotropic pressure in the background of Einstein's general theory of relativity. The Einstein's field equations have been solved by…

General Relativity and Quantum Cosmology · Physics 2021-06-23 Piyali Bhar , Pramit Rej , P. Mafa Takisa , M. Zubair

Bound states of complex scalar fields (boson stars) have long been proposed as possible candidates for the dark matter in the universe. Considerable work has already been done to study various aspects of boson stars. In the present work,…

General Relativity and Quantum Cosmology · Physics 2008-12-19 R. Sharma , S. Karmakar , S. Mukherjee

We study the hadron-quark phase transition in the interior of protoneutron stars. For the hadronic sector, we use a microscopic equation of state involving nucleons and hyperons derived within the finite-temperature…

Astrophysics · Physics 2017-08-23 O. E. Nicotra

In this work we present an exact solution of the Einstein-Maxwell field equations describing compact, charged objects within the framework of classical general relativity. Our model is constructed by embedding a four-dimensional spherically…

General Physics · Physics 2017-06-28 S. K. Maurya , M. Govender

Quasi-equilibrium models of rapidly rotating triaxially deformed stars are computed in general relativistic gravity, assuming a conformally flat spatial geometry (Isenberg-Wilson-Mathews formulation) and a polytropic equation of state.…

Astrophysics · Physics 2009-01-08 Xing Huang , Charalampos Markakis , Noriyuki Sugiyama , Koji Uryu

A charged compact star models have been determined for anisotropic fluid distribution. We have solved the Einstein's- Maxwell field equations to construct the charged compact star models by using radial pressure, metric function…

General Relativity and Quantum Cosmology · Physics 2017-08-02 Baiju Dayanandan , S. K. Maurya , Smitha T. T

The main point of this paper is a suggestion about the proper treatment of the photon gas in a theory of stellar structure and other plasmas. This problem arises in the study of polytropic gas spheres, where we have already introduced some…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Christian Fronsdal

The properties of neutron stars constituted of a crust of hadrons and an internal part of hadrons and kaon condensate are calculated within the quark-meson-coupling model. We have considered stars with nucleons only in the hadron phase and…

Astrophysics · Physics 2009-11-11 D. P. Menezes , P. K. Panda , C. Providencia

A new class of solutions describing analytical solutions for compact stellar structures has been developed within the tenets of General Relativity. Considering the inherent anisotropy in compact stars, a stable and causal model for…

General Relativity and Quantum Cosmology · Physics 2021-10-14 Jay Solanki , Bhashin Thakore

Quartic gravity theory is considered with the Einstein-Hilbert Lagrangean $R+aR^{2}+bR_{\mu \nu}R^{\mu \nu},$ $R_{\mu \nu}$ being Ricci\'s tensor and R the curvature scalar. The parameters $a$ and $b$ are taken of order 1 km$^{2}.$…

General Relativity and Quantum Cosmology · Physics 2021-06-16 Emilio Santos

This paper discusses a generalized model for compact stars, assumed to be anisotropic in nature due to the spherical symmetry and high density. After embedding the four-dimensional spacetime in a five-dimensional flat spacetime, which may…

General Physics · Physics 2018-03-09 S. K. Maurya , Debabrata Deb , Saibal Ray , P. K. F. Kuhfittig

Einstein's equations are solved for spherically symmetric universes composed of dust with tangential pressure provided by angular momentum, L(R), which differs from shell to shell. The metric is given in terms of the shell label, R, and the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 J. R. Gair

The structure of compact star core filled by gluon matter plasma is investigated within the fluid-like QCD framework. The energy momentum tensor, density and pressure relevant for gluonic plasma having the nature of fluid bulk of gluon sea…

High Energy Physics - Phenomenology · Physics 2012-03-13 C. S. Nugroho , A. O. Latief , T. P. Djun , L. T. Handoko

The inner regions of the most massive compact stellar objects might be occupied by a phase of quarks. Since the observations of the massive pulsars PSR J1614-2230 and of PSR J0348+0432 with about two solar masses, the equations of state…

Nuclear Theory · Physics 2016-03-09 Andreas Zacchi , Matthias Hanauske , Jürgen Schaffner-Bielich

A simple classification is given of the anisotropic relativistic star models, resembling the one of charged isotropic solutions. On the ground of this database, and taking into account the conditions for physically realistic star models, a…

General Relativity and Quantum Cosmology · Physics 2018-01-24 B. V. Ivanov

A very fast iterative method is presented to calculate the internal constitution of the outer crust of a cold nonaccreted neutron star, making use of very accurate analytical formulas for the transition pressures between adjacent crustal…

High Energy Astrophysical Phenomena · Physics 2020-05-25 Nicolas Chamel