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Related papers: Quantum Gravity Effects around Sagittarius A*

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We consider null and time-like geodesics around a spherically symmetric, non-rotating Coherent Quantum Black Hole (CQBH). The classical limit of the geometry of CQBH departs from that of the Schwarzschild spacetime at short scales and…

General Relativity and Quantum Cosmology · Physics 2024-06-10 Abdybek Urmanov , Hrishikesh Chakrabarty , Daniele Malafarina

A non-monotonic behavior of the velocity gradient of a test particle revolving around a rapidly rotating black hole in the locally non-rotating frame of reference is known as the Aschenbach effect. This effect can serve as a distinguishing…

General Relativity and Quantum Cosmology · Physics 2021-04-21 Ali Vahedi , Jafar Khodagholizadeh , Arman Tursunov

This article delves into the observational properties of a Schwarzschild-like black hole (BH). Initially, the research provides a succinct examination of the spacetime geometry and the configuration of its horizon. Furthermore, we study the…

General Relativity and Quantum Cosmology · Physics 2026-03-17 Weiqiang Yang , Mirzabek Alloqulov , Ahmadjon Abdujabbarov , Bobomurat Ahmedov , Chengxun Yuan , Chen Zhou

A study of the high angular momentum particles 'atmosphere' near the Schwarzschild black hole horizon suggested that strong gravitational interactions occur at invariant distance of the order of $\sqrt[3]{M}$ (A. Casher et. al). We present…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Kirill Tuchin

In this paper, optical properties of renormalization group improved (RGI) Schwarzschild black hole (BH) are investigated in plasma medium. Starting from the equations of motions in plasma medium, we have shown how the shadow radius of the…

General Relativity and Quantum Cosmology · Physics 2023-02-01 Farruh Atamurotov , Mubasher Jamil , Kimet Jusufi

In recent years it has emerged that the high energy behavior of gravity could be governed by an ultraviolet non-Gaussian fixed point of the (dimensionless) Newton's constant, whose behavior at high energy is thus {\it antiscreened}. This…

High Energy Physics - Theory · Physics 2011-08-17 Alfio Bonanno

Based on the Euclidean approach, we consider the effects of quantum gravity and mass-less matter on the thermodynamic properties of Schwarzschild black hole. The techniques of effective field theory are utilized to analytically construct…

General Relativity and Quantum Cosmology · Physics 2017-08-11 Basem Kamal El-Menoufi

In the context of an extended General Relativity theory with boundary terms included, we introduce a new nonlinear quantum algebra involving a quantum differential operator, with the aim to calculate quantum geometric alterations when a…

General Relativity and Quantum Cosmology · Physics 2024-07-08 Mauricio Bellini , Juan Ignacio Musmarra , Daniela Magos

There is rich literature on regular black holes from loop quantum gravity (LQG), where quantum geometry effects resolve the singularity, leading to a quantum extension of the classical space-time. As we will see, the mechanism that resolves…

General Relativity and Quantum Cosmology · Physics 2023-01-05 Abhay Ashtekar , Javier Olmedo , Parampreet Singh

Classical general relativity predicts that a contracting, spherically symmetric matter system with a large-enough mass will result in the formation of a trapped region whose outer boundary is an apparent horizon where the gravitational…

General Relativity and Quantum Cosmology · Physics 2026-04-01 Ram Brustein , A. J. M. Medved , Hagar Meir

We consider the quantization of the complete extension of the Schwarzschild space-time using spherically symmetric loop quantum gravity. We find an exact solution corresponding to the semi-classical theory. The singularity is eliminated but…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Rodolfo Gambini , Jorge Pullin

Schwarzschild black holes can produce strong gravitational lensing. The relativistic images are produced due to bending of light around the black hole. We propose a model equation to study the strong gravitational lensing. The model…

General Relativity and Quantum Cosmology · Physics 2012-08-17 Tushar Kanti Dey

I review several different calculations, coming from string theory, nonperturbative quantum gravity and analyses of black holes that lead to predictions of phenomena that would uniquely be signatures of quantum gravitational effects. These…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Lee Smolin

By reexamination of the boundary conditions of wave equation on a black hole horizon it is found not harmonic, but real-valued exponentially time-dependent solutions. This means that quantum particles probably do not cross the Schwarzschild…

General Physics · Physics 2018-05-10 Merab Gogberashvili , Lasha Pantskhava

In this paper we study the gravitational collapse in loop quantum gravity. We consider the space-time region inside the Schwarzschild black hole event horizon and we divide this region in two parts, the first one where the matter (dust…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Leonardo Modesto

We use exact results in a new approach to quantum gravity to study the effect of quantum loop corrections on the behavior of the metric of space-time near the Schwarzschild radius of a massive point particle in the Standard Model. We show…

High Energy Physics - Phenomenology · Physics 2009-11-10 B. F. L. Ward

Sagittarius A* (Sgr A*) -- the supermassive black hole (SMBH) in the center of our galaxy -- has been observed in most of the electromagnetic spectrum, from radio to X-rays. Diffuse gamma-ray emission has been observed around Sgr A* and a…

High Energy Astrophysical Phenomena · Physics 2021-09-08 Fabio Cafardo , Rodrigo Nemmen

The images of Sagittarius A$^*$ recently released by the Event Horizon Telescope collaboration have been accompanied [Ap.J.Lett.\,{\bf 930\,\#2}\,(2022)\,L17] by an analysis of the constraints on the possible absence of a trapping horizon,…

High Energy Astrophysical Phenomena · Physics 2022-11-01 Raúl Carballo-Rubio , Francesco Di Filippo , Stefano Liberati , Matt Visser

The accretion of galactic gas is regarded as the source of the giant luminosity of quasars. The gravitational energy converts itself into radiation close to the Schwarzschild horizon of the central supermassive black hole with efficiency of…

General Physics · Physics 2022-11-22 Janusz E. Jacak

The physical interpretation and eventual fate of gravitational singularities in a theory surpassing classical general relativity are puzzling questions that have generated a great deal of interest among various quantum gravity approaches.…

General Relativity and Quantum Cosmology · Physics 2019-11-06 Norbert Bodendorfer , Fabio M. Mele , Johannes Münch