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Related papers: Isotropic compact stars in 4D Einstein-Gauss-Bonne…

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We present a model of compact astrophysical object under General Theory of Relativity using the anisotropic extension of Tolman IV solution. The anisotropy function, derived from the model, remains well behaved throughout the interior of…

General Relativity and Quantum Cosmology · Physics 2022-06-29 Shyam Das , Bikram Keshari Parida , Koushik Chakraborty , Saibal Ray

In this paper we address two important issues which could affect reaching the exponential and Kasner asymptotes in Einstein-Gauss-Bonnet cosmologies -- spatial curvature and anisotropy in both three- and extra-dimensional subspaces. In the…

General Relativity and Quantum Cosmology · Physics 2018-05-16 Sergey A. Pavluchenko , Alexey Toporensky

We construct a compact phase space for flat FLRW spacetimes with standard matter described by a perfect fluid with a barotropic equation of state for general f(R) theories of gravity, subject to certain conditions on the function f. We then…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Mohamed Abdelwahab , Rituparno Goswami , Peter K. S. Dunsby

We present a spherically symmetric solution of the general relativistic field equations in isotropic coordinates for charged fluid with pressure anisotropy, compatible with a super dense star modeling. Further, we have constructed an…

General Physics · Physics 2015-02-12 Ksh. Newton Singh , Narendra Pradhan , Manuel Malaver

We study cosmological solutions of Einstein gravity with a positive cosmological constant in diverse dimensions. These include big-bang models that re-collapse, big-bang models that approach de Sitter acceleration at late times, and bounce…

High Energy Physics - Theory · Physics 2009-11-07 K. R. Kristjansson , L. Thorlacius

In this work, we provide a novel exact solution to the Einstein-Maxwell field equations in isotropic coordinates for charged anisotropic matter distribution, achieved by considering one of the metric potentials as well as a particular form…

General Relativity and Quantum Cosmology · Physics 2025-08-25 B S Ratanpal , Bhavesh Suthar

This work aims to investigate some possible emergence of relativistic compact stellar objects in modified $f(\mathcal{G})$ gravity using Noether symmetry approach. For this purpose, we assume static spherically symmetric spacetime in the…

General Relativity and Quantum Cosmology · Physics 2020-06-08 M. Farasat Shamir , Tayyaba Naz

We study the behavior of a general gravitational action, including quadratic terms in the curvature, supplemented by a compact scalar field in 4+1 dimensions. The generalized Einstein equation for this system admits solutions which are…

High Energy Physics - Theory · Physics 2009-10-31 Hael Collins , Bob Holdom

We study generalizations of Buchdahl's compactness limits for perfect-fluid star solutions of $D$-dimensional Einstein gravity coupled to higher-curvature corrections. We focus on Quasi-topological theories involving infinite towers of…

General Relativity and Quantum Cosmology · Physics 2026-03-27 Pablo Bueno , Robie A. Hennigar , Ángel J. Murcia , Aitor Vicente-Cano

In this paper we perform stability analysis for exponential solutions in Einstein-Gauss-Bonnet and cubic Lovelock gravity. We report our findings, provide areas on parameters space and discuss familiarities and differences between cases.…

General Relativity and Quantum Cosmology · Physics 2015-11-11 Sergey A. Pavluchenko

We present a class of new relativistic solutions with anisotropic fluid for compact stars in hydrostatic equilibrium. The interior space-time geometry considered here for compact objects are described by parameters namely, $\lambda$, $k$,…

General Relativity and Quantum Cosmology · Physics 2016-03-25 Bikash Chandra Paul , Rumi Deb

We present an algorithm to generalize a plethora of well-known solutions to Einstein field equations describing spherically symmetric relativistic fluid spheres by relaxing the pressure isotropy condition on the system. By suitably fixing…

General Physics · Physics 2018-02-14 S. Thirukkanesh , F. C. Ragel , Ranjan Sharma , Shyam Das

In this work, we investigate the emergence of compact, anisotropic stellar structures through the gravitational decoupling scheme within the framework of complete geometric deformation. The study introduces a novel synthesis of two…

General Relativity and Quantum Cosmology · Physics 2025-12-09 Z. Yousaf , Kazuharu Bamba , M. Z. Bhatti , S. Khan

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

Field theoretical scheme of regular Big Bang in 4-dimensional physical space-time, built in the framework of gauge approach to gravitation, is discussed. Regular bouncing character of homogeneous isotropic cosmological models is ensured by…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. V. Minkevich

We show that the isentropic subclass of Buchdahl's exact solution for a gaseous relativistic star is stable and gravitationally bound for all values of the compactness ratio $u [\equiv (M/R)$, where $M$ is the total mass and $R$ is the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 P. S. Negi

We consider static neutron stars within the framework of $R^2$ gravity. The neutron fluid is described by three different types of realistic equations of state (soft, moderately stiff, and stiff). Using the observational data on the neutron…

General Relativity and Quantum Cosmology · Physics 2018-06-08 Vladimir Folomeev

We present a new system of equations that fully characterizes adiabatic, radial perturbations of perfect fluid stars within the theory of general relativity. The properties of the system are discussed, and, provided that the equilibrium…

General Relativity and Quantum Cosmology · Physics 2024-05-14 Paulo Luz , Sante Carloni

Einstein-Gauss-Bonnet gravity in five-dimensional spacetime provides an excellent example of a theory that, while including higher-order curvature corrections to General Relativity, still shares many of its features, such as second-order…

High Energy Physics - Theory · Physics 2015-06-05 Fernando Izaurieta , Eduardo Rodríguez

We test Einstein gravity using cosmological observations of both expansion and structure growth, including the latest data from supernovae (Union2.1), CMB (WMAP7), weak lensing (CFHTLS) and peculiar velocity of galaxies (WiggleZ). We fit…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-21 Gong-Bo Zhao , Hong Li , Eric V. Linder , Kazuya Koyama , David J. Bacon , Xinmin Zhang