English
Related papers

Related papers: Construct a realistic stellar model with polytropi…

200 papers

A new model of charged compact star is reported by solving the Einstein-Maxwell field equations by choosing a suitable form of radial pressure. The model parameters $\rho$, $p_r$, $p_{\perp}$ and $E^{2}$ are in closed form and all are well…

General Relativity and Quantum Cosmology · Physics 2018-01-08 B. S. Ratanpal , Piyali Bhar

We consider here a full study of stellar dynamics from the brane-world point of view in the case of constant density and of a polytropic fluid. We start our study cataloguing the minimal requirements to obtain a compact object with a…

General Relativity and Quantum Cosmology · Physics 2015-07-29 Francisco X. Linares , Miguel A. Garcia-Aspeitia , L. Arturo Ureña-Lopez

We present an analytical model of the relation between the surface density of gas and star formation rate in galaxies and clouds, as a function of the presence of supersonic turbulence and the associated structure of the interstellar…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-06 Florent Renaud , Katarina Kraljic , Frédéric Bournaud

Context: The current stellar atmosphere programs still cannot match some fundamental observations of the brightest stars, and with new techniques, such as optical interferometry, providing new data for these stars, additional development of…

Astrophysics · Physics 2009-11-13 John B. Lester , Hilding R. Neilson

Matter interacts through two long range forces: gravity and electromagnetism. While all matter contributes to the gravitational potential, electromagnetic effects were traditionally expected to cancel in large systems because positive and…

Solar and Stellar Astrophysics · Physics 2026-02-25 Andrej Čadež , Aleš Mohorič , Massimo Calvani

State-of-the-art one-dimensional (1D) stellar evolution codes rely on simplifying assumptions, such as mixing length theory, in order to describe superadiabatic convection. As a result, 1D stellar structure models do not correctly recover…

Solar and Stellar Astrophysics · Physics 2019-08-07 Andreas Christ Sølvsten Jørgensen , Achim Weiss

We use replica exchange Monte-Carlo simulations to measure the equilibrium equation of state of the disordered fluid state for a binary hard sphere mixture up to very large densities where standard Monte-Carlo simulations do not easily…

Statistical Mechanics · Physics 2011-02-04 Gerardo Odriozola , Ludovic Berthier

We use the definition of complexity for static and self--gravitating objects to build up three physical general relativistic anisotropic models fulfilling the vanishing complexity condition which serves to provide the extra information…

General Relativity and Quantum Cosmology · Physics 2022-08-24 C. Arias , E. Contreras , E. Fuenmayor , A. Ramos

We argue that an arbitrary general relativistic static anisotropic fluid sphere, (static and spherically symmetric but with transverse pressure not equal to radial pressure), can nevertheless be successfully mimicked by suitable linear…

General Relativity and Quantum Cosmology · Physics 2017-11-29 Petarpa Boonserm , Tritos Ngampitipan , Matt Visser

Equations of state for a cold neutron star's interior are presented in three-column tables that relate the baryonic density, the energy density, and the pressure. A few analytical expressions for those tables have been established these…

Nuclear Theory · Physics 2022-10-05 Lami Suleiman , Morgane Fortin , Julian-Leszek Zdunik , Constanca Providencia

The macroscopic properties of compact stars in modified gravity theories can be significantly different from the general relativistic (GR) predictions. Within the gravitational context of scalar-tensor theories, with a scalar field $\phi$…

General Relativity and Quantum Cosmology · Physics 2023-12-05 Juan M. Z. Pretel , Sergio E. Jorás , Ribamar R. R. Reis , Sergio B. Duarte , José D. V. Arbañil

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

Within the framework of Einstein's General Relativity we study strange quark stars assuming an interacting equation-of-state. Taking into account the presence of anisotropies in a sphere made of ultra dense matter, we employ the formalism…

General Relativity and Quantum Cosmology · Physics 2023-03-09 Angel Rincon , Grigoris Panotopoulos , Ilidio Lopes

According to the so-called "global polytropic model", hydrostatic equilibrium for a planetary system leads to the Lane-Emden differential equation. Solving this equation in the complex plane, we obtain polytropic spherical shells defined by…

Earth and Planetary Astrophysics · Physics 2015-01-20 Vassilis S. Geroyannis

The main objective of this article is to study the viable compact stellar structures in non-Riemannian geometry, i.e., $f(\mathbb{Q},T)$ theory, where $\mathbb{Q}$ defines the non-metricity and $T$ represents trace of the stress-energy…

General Relativity and Quantum Cosmology · Physics 2024-04-02 M. Zeeshan Gul , M. Sharif , Adeeba Arooj

We present a simple, analytic and straightforward method to elucidate the effects produced by polytropic fluids on any other gravitational source, no matter its nature, for static and spherically symmetric spacetimes. As a direct…

General Relativity and Quantum Cosmology · Physics 2022-03-30 J. Ovalle , E. Contreras , Z. Stuchlik

The isothermal gas sphere is a particular type of Lane-Emden equation and is used widely to model many problems in astrophysics like stars, star clusters, and the formation of galaxies. In this paper, we present a computational scheme to…

Astrophysics of Galaxies · Physics 2021-03-31 Yosry A. Azzam , Emad A. -B. Abdel-Salam , Mohamed I. Nouh

We examine contributions of second order physical processes to results of stellar evolution calculations amenable to direct observational testing. In the first paper in the series (Young et al. 2001) we established baseline results using…

Astrophysics · Physics 2009-11-10 Patrick A. Young , David Arnett

We study the scalar field potential $V(\phi)$ in the scalar-tensor gravity with self-consistent polytropic stellar configurations. Without choosing a particular potential, we numerically derive the potential inside various stellar objects.…

General Relativity and Quantum Cosmology · Physics 2015-05-20 Kaisa Henttunen , Iiro Vilja

We construct stationary axisymmetric solutions of the Euler-Poisson equations, which govern the internal structure of polytropic gaseous stars, with small constant angular velocity when the adiabatic exponent $\gamma$ belongs to…

Analysis of PDEs · Mathematics 2017-04-26 Juhi Jang , Tetu Makino