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Related papers: Black Hole Shadow in Symmergent Gravity

200 papers

The classic black hole mechanics and thermodynamics are formulated for stationary black holes with event horizons. Alternative theories of gravity of interest for cosmology contain a built-in time-dependent cosmological "constant" and black…

General Relativity and Quantum Cosmology · Physics 2018-10-12 Valerio Faraoni

Several properties of canonical quantum gravity modify space-time structures, sometimes to the degree that no effective line elements exist to describe the geometry. An analysis of solutions, for instance in the context of black holes, then…

General Relativity and Quantum Cosmology · Physics 2011-11-04 Martin Bojowald , George M. Paily , Juan D. Reyes , Rakesh Tibrewala

We study the shadow of a charged rotating black hole in $f(R)$ gravity. This black hole is characterized by mass, $M$, spin, $a$, electric charge, $Q$ and $R_{0}$ which is proportional to cosmological constant. We analyze the image of the…

General Relativity and Quantum Cosmology · Physics 2022-10-06 Sara Dastan , Reza Saffari , Saheb Soroushfar

We review some recent results obtained for black holes using effective field theory methods applied to quantum gravity, in particular the unique effective action. Black holes are complex thermodynamical objects that not only have a…

High Energy Physics - Theory · Physics 2022-02-08 Xavier Calmet , Folkert Kuipers

The groundbreaking image of the black hole at the center of the M87 galaxy has raised questions at the intersection of observational astronomy and black hole physics. How well can the radius of a black hole shadow can be measured, and can…

General Relativity and Quantum Cosmology · Physics 2022-02-02 Adam Bauer , Alejandro Cárdenas-Avendaño , Charles F. Gammie , Nicolás Yunes

The existence of black holes is a central prediction of general relativity and thus serves as a basic consistency test for modified theories of gravity. In spherical symmetry, only two classes of dynamic solutions are compatible with the…

General Relativity and Quantum Cosmology · Physics 2022-03-01 Sebastian Murk

A renormalizable theory of quantum gravity coupled to a dilaton and conformal matter in two space-time dimensions is analyzed. The theory is shown to be exactly solvable classically. Included among the exact classical solutions are…

High Energy Physics - Theory · Physics 2009-09-17 C. Callan , S. Giddings , J. Harvey , A. Strominger

Astrophysical black hole candidates, although long thought to have a horizon, could be horizonless ultra-compact objects. This intriguing possibility is motivated by the black hole information paradox and a plausible fundamental connection…

General Relativity and Quantum Cosmology · Physics 2017-04-26 Bob Holdom , Jing Ren

Effective field theory methods suggest that some rather-general extensions of General Relativity include, or are mimicked by, certain higher-order curvature corrections, with coupling constants expected to be small but otherwise arbitrary.…

General Relativity and Quantum Cosmology · Physics 2023-08-29 Vitor Cardoso , Masashi Kimura , Andrea Maselli , Leonardo Senatore

First sketch of black hole from M87 galaxy was obtained by Event Horizon Telescope, recently. As appearance of black hole shadow reflects space-time geometry of black holes, observations of black hole shadow may be a promising way to test…

General Relativity and Quantum Cosmology · Physics 2020-06-30 Zhe Chang , Qing-Hua Zhu

We study the equivalence principle, regarded as the cornerstone of general relativity, by analyzing the deformation observable of black hole shadows. Such deformation can arise from new physics and may be expressed as a phenomenological…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-22 Chunlong Li , Sheng-Feng Yan , Lingqin Xue , Xin Ren , Yi-Fu Cai , Damien A. Easson , Ye-Fei Yuan , Hongsheng Zhao

Emergent modified gravity provides a covariant, effective framework for obtaining spherically symmetric black hole solutions in models of loop quantum gravity with scale-dependent holonomy modifications. Exact solutions for vacuum black…

General Relativity and Quantum Cosmology · Physics 2024-07-18 Idrus Husin Belfaqih , Martin Bojowald , Suddhasattwa Brahma , Erick I. Duque

We construct quartic quasitopological gravity, a theory of gravity containing terms quartic in the curvature that yields second order differential equations in the spherically symmetric case. Up to a term proportional to the quartic term in…

High Energy Physics - Theory · Physics 2015-05-30 M. H. Dehghani , A. Bazrafshan , R. B. Mann , M. R. Mehdizadeh , M. Ghanaatian , M. H. Vahidinia

We study the shadow produced by a class of rotating black holes surrounded by plasma. The metric for these black holes arises by applying the Newman-Janis algorithm to a family of spherically symmetric spacetimes, which includes several…

General Relativity and Quantum Cosmology · Physics 2021-11-08 Javier Badía , Ernesto F. Eiroa

Analogue gravity studies the physics of curved spacetime in laboratory experiments, where the propagation of elementary excitations in inhomogeneous flows is mapped to those of scalar fields in a curved spacetime metric. While most analogue…

In the context of the recently proposed type-II minimally modified gravity theory, i.e. a metric theory of gravity with two local physical degrees of freedom that does not possess an Einstein frame, we study spherically symmetric vacuum…

General Relativity and Quantum Cosmology · Physics 2021-03-12 Antonio De Felice , Andreas Doll , François Larrouturou , Shinji Mukohyama

In this work, we probe the weak gravitational lensing by a static spherically symmetric black hole in view of $f(R)$ gravity in the background of the non-plasma medium (vacuum). We provide a discussion on a light ray in a static black hole…

General Relativity and Quantum Cosmology · Physics 2023-11-01 Surajit Mandal

While spacetime in the vicinity outside astrophysical black holes is believed to be well understood, the event horizon and the interior remain elusive. Here, we discover a degenerate infinite spectrum of novel general relativity solutions…

General Relativity and Quantum Cosmology · Physics 2022-04-18 Zacharias Roupas

This work focuses on the examination of a regular black hole within Verlinde's emergent gravity, specifically investigating the Hayward-like (modified) solution. The study reveals the existence of three horizons under certain conditions,…

General Relativity and Quantum Cosmology · Physics 2024-06-10 A. A. Araújo Filho

Emergent modified gravity provides a covariant framework for holonomy effects in models of loop quantum gravity with consistent black hole solutions coupled to a scalar field. Several independent studies of the Hawking thermal distribution…

General Relativity and Quantum Cosmology · Physics 2026-02-13 Idrus Husin Belfaqih , Martin Bojowald , Suddhasattwa Brahma , Erick I. Duque