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Related papers: Compact objects in unimodular gravity

200 papers

We study the modified Reissner Nordstrom metric in the unimodular gravity. So far the spherical symmetric Einstein field equation in unimodular gravity has been studied in the absence of any source. We consider static electric and magnetic…

General Relativity and Quantum Cosmology · Physics 2017-07-26 Pankaj Chaturvedi , Naveen K. Singh , Dharm Veer Singh

Noncommutative geometry may be a starting point to a quantum gravity. We study the influence of the spacetime noncommutative parameter on the strong field gravitational lensing in the noncommutative Schwarzschild black-hole spacetime and…

General Relativity and Quantum Cosmology · Physics 2011-04-22 Chikun Ding , Shuai Kang , Chang-Yong Chen , Songbai Chen , Jiliang Jing

Some cosmological solutions of the unimodular theory of gravity are studied. These solutions can always be mapped to solutions of Einstein's general relativity in an appropiate frame. Constant scalar potentials however do not gravitate.…

High Energy Physics - Theory · Physics 2013-10-14 Enrique Alvarez , Mario Herrero-Valea

Astrophysical compact objects are studied in the context of quadratic non-metricity gravity. The solutions to the gravitational field equations, which include fluid components, are analyzed to investigate the density and pressure properties…

General Relativity and Quantum Cosmology · Physics 2025-07-24 G. G. L. Nashed , Kazuharu Bamba

In this article, we construct a broad family of spacetimes with spherically symmetric thin shells in unimodular gravity. We present the framework for the analysis of the dynamical stability of the configurations under perturbations…

General Relativity and Quantum Cosmology · Physics 2025-06-11 Gabriel R. Bengochea , Ernesto F. Eiroa , Griselda Figueroa-Aguirre

We consider the effects of a cosmological constant on the dynamics of constant angular momentum discs orbiting Schwarzschild-de Sitter black holes. The motivation behind this study is to investigate whether the presence of a radial force…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Luciano Rezzolla , Olindo Zanotti , Jose A. Font

The recent observations of neutron star mergers have changed our perspective on scalar- tensor theories of gravity, favouring models where gravitational waves travel at the speed of light. In this work we consider a scalar-tensor set-up…

General Relativity and Quantum Cosmology · Physics 2018-08-15 Javier Chagoya , Gianmassimo Tasinato

The so-called unimodular version of General Relativity is revisited. Unimodular gravity is constructed by fixing the determinant of the metric, what leads to the trace-free part of the equations instead of the usual Einstein field…

General Relativity and Quantum Cosmology · Physics 2016-06-22 Diego Saez-Gomez

An effective theory of gravity in the infrared is proposed, which involves the determinant of the metric relative to the determinant of a prior metric taken to be that of Minkowski spacetime. This effective theory can be interpreted as a…

High Energy Physics - Theory · Physics 2017-02-15 F. R. Klinkhamer

The explicit violation of the general gauge invariance/relativity is adopted as the origin of dark matter and dark energy of the gravitational nature. The violation of the local scale invariance alone, with the residual unimodular one, is…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Yu. F. Pirogov

We apply the recent results in Loop Quantum Cosmology and in the resolution of Black Hole singularity to the gravitational collapse of a star. We study the dynamic of the space time in the interior of the Schwarzschild radius. In particular…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Leonardo Modesto

A new spherically-symmetric solution for a gravitational field is found in the conformally-unimodular metric. It is shown, that the surface of the black hole horizon in the standard Schwarzschild metric can be squeezed to a point by…

General Relativity and Quantum Cosmology · Physics 2020-08-24 Sergey L. Cherkas , Vladimir L. Kalashnikov

We study the quantum dynamics of an interior planar AdS (anti-de Sitter) black hole, requiring unitarity in the natural time coordinate conjugate to the cosmological "constant of motion" appearing in unimodular gravity. Both the classical…

High Energy Physics - Theory · Physics 2025-03-12 Steffen Gielen , Lucía Menéndez-Pidal

A quest for phenomenological footprints of quantum gravity is among the central scientific tasks in the rising era of gravitational wave astronomy. We study gravitational wave dynamics within the noncommutative geometry framework, based on…

General Relativity and Quantum Cosmology · Physics 2024-05-24 Nikola Herceg , Tajron Jurić , Andjelo Samsarov , Ivica Smolić , Kumar S. Gupta

In this paper we will investigate the effects of a noncommutative (NC) space-time on the dynamics of the universe. We will generalize the black hole entropy formula for a NC black hole. Then, using the entropic gravity formalism, we will…

General Relativity and Quantum Cosmology · Physics 2016-10-06 Rafael C. Nunes , Hooman Moradpour , Edésio M. Barboza , Everton M. C. Abreu , Jorge Ananias Neto

Black holes are the most compact objects in the Universe. According to general relativity, black holes have a horizon that hides a singularity where Einstein's theory breaks down. Recently, gravitational waves opened the possibility to…

General Relativity and Quantum Cosmology · Physics 2022-12-01 Elisa Maggio

In this review we discuss emergence of unimodular gravity (or, more precisely, Weyl transverse gravity) from thermodynamics of spacetime. By analyzing three different ways to obtain gravitational equations of motion by thermodynamic…

General Relativity and Quantum Cosmology · Physics 2022-04-19 Ana Alonso-Serrano , Marek Liška

We review selected aspects of unimodular gravity and we discuss its viability as a solution of the old cosmological constant problem. In unimodular gravity the cosmological constant is promoted to a global degree of freedom. We highlight…

General Relativity and Quantum Cosmology · Physics 2023-01-05 Pavel Jiroušek

A thorough study and analysis on the conceptual foundations of unimodular gravity shows that this theory is essentially general relativity disguised as unimodular relativity in the literature. The main reason for this dilemma is accepting…

General Physics · Physics 2023-06-09 S. C. Tiwari

In this work, we present the new technique for discussing the dynamical motion of neutral as well as charged particles in the absence/presence of magnetic field around the time conformal Schwarzschild black hole. Initially, we find the…

General Physics · Physics 2016-11-23 Abdul Jawad , Farhad Ali , M. Umair Shahzad , G. Abbas