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Related papers: Anisotropic Stars: Exact Solutions

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We have proposed a model for relativistic compact star with anisotropy and analytically obtained exact spherically symmetric solutions describing the interior of the dense star admitting non-static conformal symmetry. Several features of…

General Relativity and Quantum Cosmology · Physics 2016-04-27 Dibyendu Shee , Farook Rahaman , B. K. Guha , Saibal Ray

It is well known that a spherically symmetric constant density static star, modeled as a perfect fluid, possesses a bound on its mass m by its radial size R given by 2m/R \le 8/9 and that this bound continues to hold when the energy density…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Jemal Guven , Niall O' Murchadha

Neutron stars may exhibit pressure anisotropy arising from various physical mechanisms, such as elasticity, magnetic fields, viscosity, and superfluidity. We compute the tidal deformability and the $f$-mode oscillation frequency of…

High Energy Astrophysical Phenomena · Physics 2026-02-17 Victor Guedes , Siddarth Ajith , Shu Yan Lau , Kent Yagi

This paper examines the general formalism and applications of isotropic as well as anisotropic polytropic stars in curvature-matter coupled gravity. For this purpose, we consider static spherical and Schwarzschild spacetimes in the interior…

General Relativity and Quantum Cosmology · Physics 2022-02-16 M. Sharif , Amal Majid , M. Shafaqat

In several classes of modified gravity theories, extra degrees of freedom are not completely screened in the interiors of stellar and substellar objects. In such theories, the hydrostatic equilibrium condition inside these objects is…

General Relativity and Quantum Cosmology · Physics 2023-10-27 Shaswata Chowdhury

An anisotropic fluid with variable energy density and negative pressure is proposed, both outside and inside stars. The gravitational field is constant everywhere in free space (if we neglect the local contributions) and its value is of the…

General Relativity and Quantum Cosmology · Physics 2015-05-27 Hristu Culetu

In this work, we made an extensive study about the possible presence of anisotropies in strange stars. To accomplish this task, we use three different configurations for the strange matter: the unpaired matter, a two-flavor super-conducting…

High Energy Physics - Phenomenology · Physics 2024-02-21 Luiz L. Lopes , H. C. Das

In this paper we study anisotropic spherical polytropes within the framework of general relativity. Using the anisotropic Tolman-Oppenheimer-Volkov (TOV) equations, we explore the relativistic anisotropic Lane-Emden equations. We find how…

General Relativity and Quantum Cosmology · Physics 2016-07-20 F. Shojai , M. Kohandel , A. Stepanian

In this work, we study the impact of anisotropy on slowly rotating neutron stars by extending the Hartle-Thorne formalism in general relativity to include anisotropy in pressure up to second order in the angular velocity. We assess the…

General Relativity and Quantum Cosmology · Physics 2024-10-10 L. M. Becerra , E. A. Becerra-Vergara , F. D. Lora-Clavijo

Dev (2002) discussed some exact solutions of anisotropic stars for special forms of TOV for constant energy density. Considering Bijalwan (2011) ansatz for charged perfect fluids we present here some exact solutions to the generalized TOV…

General Physics · Physics 2011-09-26 Naveen Bijalwan

The applicability of the potential approximation in the case of open universes is tested. Great Attractor-like structures are considered in the test. Previous estimates of the Cosmic Microwave background anisotropies produced by these…

Astrophysics · Physics 2009-10-30 Vicent Quilis , Diego Saez

The structure and stability of quark stars (QSs) made of interacting quark matter are discussed in this study, taking color superconductivity and perturbative QCD corrections into account. By combining this EoS with the…

High Energy Physics - Theory · Physics 2025-06-12 Takol Tangphati , İzzet Sakallı , Ayan Banerjee , Anirudh Pradhan

If the augmented density of a spherical anisotropic system is assumed to be multiplicatively separable to functions of the potential and the radius, the radial function, which can be completely specified by the behavior of the anisotropy…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-21 J. An

The equilibrium configurations of slowly rotating anisotropic self-gravitating fluids are computed using the extended Hartle structure equations, including anisotropic effects, derived in our previous paper. We focus on the so-called…

General Relativity and Quantum Cosmology · Physics 2025-10-20 Philip Beltracchi , Camilo Posada

In this article we obtain a new anisotropic solution for Einstein's field equation of embedding class one metric. The solution is representing the realistic objects such as $Her~X-1$ and $RXJ~1856-37$. We perform detailed investigation of…

General Physics · Physics 2016-04-27 S. K. Maurya , Y. K. Gupta , Baiju Dayanandan , Saibal Ray

We use gravitational wave (GW) and electromagnetic (EM) observations of GW170817 to constrain the extent of pressure anisotropy in it. While it is quite likely that the pressure inside a neutron star is mostly isotropic, certain physical…

General Relativity and Quantum Cosmology · Physics 2019-05-08 Bhaskar Biswas , Sukanta Bose

In this paper we are concerned with the effects of anisotropic pressure on the boundary conditions of anisotropic Lane-Emden equation and homology theorem. Some new exact solutions of this equation are derived. Then some of the theorems…

General Relativity and Quantum Cosmology · Physics 2015-07-10 F. Shojai , M. R. Fazel , A. Estepanian , M. Kohandel

We extract new classes of anisotropic solutions in the framework of mimetic gravity, by applying the Tolman-Finch-Skea metric and a specific anisotropy not directly depending on it, and by matching smoothly the interior anisotropic solution…

General Relativity and Quantum Cosmology · Physics 2023-04-19 G. G. L. Nashed , Emmanuel N. Saridakis

We investigate whether compact stars having Tolman-like interior geometry admit conformal symmetry. Taking anisotropic pressure along the two principal directions within the compact object, we obtain physically relevant quantities such as…

General Relativity and Quantum Cosmology · Physics 2016-07-25 Farook Rahaman , Sunil D. Maharaj , Iftikar Hossain Sardar , Koushik Chakraborty

We study nonaxisymmetric perturbations of rotating relativistic stars. modeled as perfect-fluid equilibria. Instability to a mode with angular dependence $\exp(im\phi)$ sets in when the frequency of the mode vanishes. The locations of these…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Nikolaos Stergioulas , John L. Friedman