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Related papers: Anisotropic Compact stars with variable cosmologic…

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In present paper a new compact star model in f(R,T) gravity is obtained where R and T denote the Ricci scalar and the trace of energy-momentum tensor $T_{\mu \nu}$ respectively. To develop the model we consider the spherically symmetric…

General Relativity and Quantum Cosmology · Physics 2021-06-01 Piyali Bhar

We present a model for compact stars in the low mass X-ray binaries(LMXBs) and X-ray pulsars using a metric given by John J. Matese and Patrick G. Whitman \citep{Matese and Whitman1980}. Here the field equations are reduced to a system of…

General Relativity and Quantum Cosmology · Physics 2014-10-02 Mehedi Kalam , Sk. Monowar Hossein , Sajahan Molla

We present a systematic investigation of the cosmological constant effects in compact stars interiors in the framework of Einstein's gravity. Consideration of a cosmological constant $\Lambda$ in compact stars is motivated by the mechanism…

High Energy Astrophysical Phenomena · Physics 2019-02-05 Noshad Khosravi Largani , David E. Alvarez-Castillo

We investigate realistic models of compact objects, focusing on neutron and strange stars, composed by dense matter and dark energy in the form of a simple fluid or scalar field interacting with matter. For the dark energy component, we use…

General Relativity and Quantum Cosmology · Physics 2023-08-01 Artyom V. Astashenok , Sergey D. Odintsov , Vasilis K. Oikonomou

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 anisotropic compact stars comprising two non-interacting fluids: quark matter and condensed dark matter. Using the MIT Bag model equation of state for quark matter and Bose-Einstein Condensate equation of state for dark…

General Relativity and Quantum Cosmology · Physics 2025-05-28 G. Panotopoulos , A. Rincón , I. Lopes

This study deals with the formation and evolution of a strange star in the Krori Barua Rainbow spacetime from collapsing charged stringy quark matter. The dynamical variables are explored from the field equations, taking into account the…

General Relativity and Quantum Cosmology · Physics 2024-01-26 Wasib Ali , Umber Sheikh

In this paper, we develop a new relativistic compact stellar model for a spherically symmetric anisotropic matter distribution. The model has been obtained through generating a new class of solutions by invoking the Tolman {\em ansatz} for…

General Relativity and Quantum Cosmology · Physics 2020-11-25 Piyali Bhar , Shyam Das , Bikram Keshari Parida

The conceptual difficulties associated with a cosmological constant have led to the investigation of alternative models in which the equation of state parameter, $w=p/\rho$, of the dark energy evolves with time. We show that combining the…

Astrophysics · Physics 2007-05-23 H. K. Jassal , J. S. Bagla , T. Padmanabhan

We derive the equation for pressure within a neutron star, taking into account a non-zero cosmological constant ($\Lambda$). We then examine the stability of the neutron star's equilibrium state in the presence of cosmological constant. Our…

General Relativity and Quantum Cosmology · Physics 2025-04-22 Naveen K. Singh , Gopal Kashyap

This study simulates the characteristics of spherically symmetric, anisotropic compact stellar bodies with electrical charge within the framework of the $f(Q)$ theory of gravity. Employing the Krori-Barua metric ansatz (K.D. Krori, J.…

General Relativity and Quantum Cosmology · Physics 2024-11-05 Debadri Bhattacharjee , Pradip Kumar Chattopadhyay

We numerically construct compact stars in the scalar-tensor theory of gravity with non-minimal derivative coupling of a scalar field to the curvature and nonzero cosmological constant. There are two free parameters in this model of gravity:…

General Relativity and Quantum Cosmology · Physics 2025-04-08 P. E. Kashargin , A. A. Lebedev , S. V. Sushkov

We propose and investigate a class of dynamical dark energy models in which the cosmological constant evolves from negative values in the early Universe to a positive value at low redshifts. This framework includes a generalised ladder-step…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-20 Mariam Bouhmadi-López , Beñat Ibarra-Uriondo

This paper investigates a spherically symmetric compact relativistic body with isotropic pressure profiles within the framework of general relativity. In order to solve the Einstein's field equations, we have considered the Vaidya-Tikekar…

Astrophysics of Galaxies · Physics 2021-11-29 Jitendra Kumar , Puja Bharti

Interested in the collapse of a radiating star, we study the temporal evolution of a fluid with heat flux and bulk viscosity, including anisotropic pressure. As a starting point, we adopt an initial configuration that satisfies the…

General Relativity and Quantum Cosmology · Physics 2018-11-27 L. S. M. Veneroni , M. F. A. da Silva

The main purpose of this paper is to obtain physically stable stellar models coupled with anisotropic matter distribution in the context of $f(\mathcal{R},\mathrm{T}^{2})$ theory. For this, we consider a static spherical geometry and…

General Relativity and Quantum Cosmology · Physics 2024-06-06 Tayyab Naseer , M. Sharif , Sana Manzoor , Arooj Fatima

We obtain a class of anisotropic spherically symmetric relativistic solutions of compact objects in hydrostatic equilibrium in the $f(R,T) =R+2\chi T$ modified gravity, where $R$ is the Ricci scalar, $T$ is the trace of the energy momentum…

General Physics · Physics 2020-09-18 S. Dey , A. Chanda , B. C. Paul

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

In this work we obtain an anisotropic neutron star solution by gravitational decoupling starting from a perfect fluid configuration which has been used to model the compact object PSR J0348+0432. Additionally, we consider the same solution…

General Relativity and Quantum Cosmology · Physics 2019-10-14 Victor Torres , Ernesto Contreras

The gravitational-wave signal GW190814 involves a compact object with mass $(2.50-2.67){\rm M}_\odot$ within the so-called low mass gap. As yet, a general consensus on its nature, being a black hole, a neutron star or an exotic star, has…

General Relativity and Quantum Cosmology · Physics 2021-02-02 Zacharias Roupas