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Related papers: Nonlocal star as a blackhole mimicker

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Unimodular gravity provides a theoretical framework that allows for non-conservation of energy-momentum, with possible implications for the cosmological constant problem. It is then important to study the predictions of unimodular gravity…

General Relativity and Quantum Cosmology · Physics 2019-09-11 J. A. Astorga-Moreno , Javier Chagoya , J. C. Flores-Urbina , Miguel A. Garcia-Aspeitia

A star surrounded by a black hole generated by it is analyzed. For an outer static observer the black hole mass (and radius) depends on his position in the gravitational field of the star. In spite of the black hole presence, the geometry…

General Relativity and Quantum Cosmology · Physics 2011-05-23 Hristu Culetu

We consider the Schwarzschild black hole and show how, in a theory with limiting curvature, the physical singularity "inside it" is removed. The resulting spacetime is geodesically complete. The internal structure of this nonsingular black…

General Relativity and Quantum Cosmology · Physics 2017-04-18 Ali H. Chamseddine , Viatcheslav Mukhanov

We investigate static spherically symmetric solutions within the framework of the local limit of nonlocal gravity. This theory departs from Einstein's general relativity (GR) through the introduction of a scalar gravitational susceptibility…

General Relativity and Quantum Cosmology · Physics 2025-09-25 Yahya Mohammadi , Javad Tabatabaei , Shant Baghram , Bahram Mashhoon

Anisotropic stresses are ubiquitous in nature, but their modeling in General Relativity is poorly understood and frame dependent. We introduce the first study on the dynamical properties of anisotropic self-gravitating fluids in a covariant…

General Relativity and Quantum Cosmology · Physics 2019-06-05 Guilherme Raposo , Paolo Pani , Miguel Bezares , Carlos Palenzuela , Vitor Cardoso

The Kerr-Newman metric is the unique vacuum solution of the General Relativistic field equations, in which any singularities or spacetime pathologies are hidden behind horizons. They are believed to describe the spacetimes of massive…

General Relativity and Quantum Cosmology · Physics 2023-04-21 Dimitrios Psaltis

A gravitational theory is formulated by considering the physical processes underlying relativistic dilation of time and contraction of space. It is shown that the point mass solution of general relativity's field equation - the…

General Relativity and Quantum Cosmology · Physics 2015-08-25 James W. Douglass

In this article, we attempt to find a singularity free solution of Einstein's field equations for compact stellar objects, precisely strange (quark) stars, considering Schwarzschild metric as the exterior spacetime. To this end, we consider…

General Relativity and Quantum Cosmology · Physics 2017-10-19 Debabrata Deb , Sourav Roy Chowdhury , Saibal Ray , Farook Rahaman , B. K. Guha

The Buchdahl star is the limiting compactness (which is indicated by sturation of the Buchdahl bound) object without horizon. It is in general defined by the potential felt by radially falling timelike particle, $\Phi(R) = 4/9$, in the…

General Relativity and Quantum Cosmology · Physics 2023-11-10 Naresh Dadhich

This paper explores the theoretical implications of quantum gravity by analyzing compact stellar objects, presenting three distinct models that serve as alternatives to traditional black holes. These models are characterized by their…

General Relativity and Quantum Cosmology · Physics 2025-12-02 Salvatore Samuele Sirletti , Piero Nicolini , Mariafelicia De Laurentis

Recently the non-local gravity theory has come out to be a good candidate for an effective field theory of quantum gravity and also it can provide rich phenomenology to understand late-time accelerating expansion of the universe. For any…

General Relativity and Quantum Cosmology · Physics 2019-08-23 Utkarsh Kumar , Sukanta Panda , Avani Patel

The frozen star model provides a classical description of a regularized black hole and is based upon the idea that regularizing the singularity requires deviations from the Schwarzschild geometry which extend over horizon-sized scales, as…

General Relativity and Quantum Cosmology · Physics 2023-04-12 Ram Brustein , A. J. M. Medved , Tom Shindelman

We examine the status of the threat posed to stellar-mass black hole candidates by the possible existence of Q-stars (compact objects with an exotic equation of state which might have masses well above the normally-accepted maximum for…

Astrophysics · Physics 2020-11-25 J. C. Miller , T. Shahbaz , L. A. Nolan

We study equilibrium configurations of a homogenous ball of matter in a bootstrapped description of gravity which includes a gravitational self-interaction term beyond the Newtonian coupling. Both matter density and pressure are accounted…

General Relativity and Quantum Cosmology · Physics 2020-01-08 Roberto Casadio , Michele Lenzi , Octavian Micu

The implications of the recent classical nonlocal generalization of Einstein's theory of gravitation for gravitational physics in the Solar System are investigated. In this theory, the nonlocal character of gravity appears to simulate dark…

General Relativity and Quantum Cosmology · Physics 2016-03-23 C. Chicone , B. Mashhoon

A novel idea is proposed for a natural solution of the dark energy and its cosmic coincidence problem. The existence of local antigravity sources, associated with astrophysical matter configurations distributed throughout the universe, can…

General Relativity and Quantum Cosmology · Physics 2018-07-04 Georgios Kofinas , Vasilios Zarikas

$Q$-stars are a class of boson stars arising in scalar-field theories with interacting potentials, minimally coupled to gravity. We show that, in certain regions of parameter space, the angular velocity of stable timelike circular geodesics…

General Relativity and Quantum Cosmology · Physics 2026-03-19 Víctor Jaramillo , Laura Meneses , Héctor R. Olivares Sánchez , Carlos Herdeiro , Darío Núñez , Shuang-Yong Zhou

We study the self-force acting on a static charged point-like particle near a Schwarzschild black hole. We obtain the point-like particle as a limit of a spacetime describing a big neutral black hole with a small charged massive object…

General Relativity and Quantum Cosmology · Physics 2020-07-24 Pavel Krtouš , Andrei Zelnikov

We present a model of relativistic elastic stars featuring scale invariance. This implies a linear mass-radius relation and the absence of a maximum mass. The most compact spherically symmetric configuration that is radially stable and…

General Relativity and Quantum Cosmology · Physics 2024-04-05 Artur Alho , José Natário , Paolo Pani , Guilherme Raposo

Boson stars coupled to Einstein's general relativity possess some features similar to gravastars, such as the anisotropy in principal pressures and relatively large compactness ($\mu_{max} = 0.32$). However, no matter how large the…

General Relativity and Quantum Cosmology · Physics 2015-12-18 Anja Marunovic