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Related papers: Asymptotic safety casts its shadow

200 papers

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

In this paper, we investigate the strong gravitational lensing effects and optical appearances around a spherically symmetric regular black hole, whose metric is derived from a non-singular collapsing dust ball model in asymptotically safe…

General Relativity and Quantum Cosmology · Physics 2025-12-02 Xiao-Jun Gao

Vacuum spherically symmetric loop quantum gravity in the midi-superspace approximation using inhomogeneous horizon-penetrating slices has been studied for a decade, and it has been noted that the singularity is eliminated. It is replaced by…

General Relativity and Quantum Cosmology · Physics 2024-02-20 Rodolfo Gambini , Javier Olmedo , Jorge Pullin

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

We investigate the effects of higher order curvature corrections to Einstein's Gravity on the critical phenomenon near the black hole threshold, namely the Choptuik phenomenon. We simulate numerically a five dimensional spherically…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Sveta Golod , Tsvi Piran

The Event Horizon Telescope (EHT) is taking the first images of black holes resolved at horizon scales to measure their shadows and probe accretion physics. A promising avenue for testing the hypothesis that astrophysical black holes are…

High Energy Astrophysical Phenomena · Physics 2020-06-17 Lia Medeiros , Dimitrios Psaltis , Feryal Özel

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

This work is devoted to the study of the optical properties of the charged-rotating-NUT-Kiselev (CRNK) black hole in the Rastall theory of gravity. By investigating the motion of photons in the CRNK black hole spacetime in the Rastall…

General Relativity and Quantum Cosmology · Physics 2022-05-25 Bakhtiyor Narzilloev , Ibrar Hussain , Ahmadjon Abdujabbarov , Bobomurat Ahmedov

The Galactic Center black hole environment gives us new opportunity to test deviation from General Relativity and black hole physics. In this work we analytically generate the shape of the Galactic Center black hole by using a recently…

General Relativity and Quantum Cosmology · Physics 2026-01-27 Pranjali Bhattacharjee , Sanjeev Kalita , Debojit Paul

The apparent shadow of a black hole provides one of the most direct probes of strong-field general relativity. While the shadow size in asymptotically flat spacetimes is well understood, the influence of cosmic expansion on its apparent…

General Relativity and Quantum Cosmology · Physics 2026-05-26 Debarshi Mukherjee

Mimetic gravity has gained significant appeal in cosmological contexts, but static spherically symmetric space-times within the baseline theory are highly non-trivial: the two natural solutions are a naked singularity and a black hole…

General Relativity and Quantum Cosmology · Physics 2024-11-07 Mohsen Khodadi , Sunny Vagnozzi , Javad T. Firouzjaee

We study black holes with linear equation of state within the framework of asymptotically safe gravity. This study extends previous work on gravitational collapse in asymptotically safe gravity (that has been done for a dust fluid) by…

General Relativity and Quantum Cosmology · Physics 2026-02-17 Ramin Hassannejad , Fatimah Shojai , Kazuharu Bamba

The general parametrization of spherically symmetric and asymptotically flat black-hole spacetimes in arbitrary metric theories of gravity was suggested in [3]. The parametrization is based on the continued fraction expansion in terms of…

General Relativity and Quantum Cosmology · Physics 2022-05-18 R. A. Konoplya , A. Zhidenko

One of the main goals of contemporary theoretical physics is to find the quantum theory of gravity. There are various working hypotheses, mostly operating in the regime of high-energy physics well above the reach of particle accelerators.…

General Relativity and Quantum Cosmology · Physics 2022-04-01 Samuel Kováčik

With the imaging and characterization of the horizon-scale images of M87* and Sgr A* by the Event Horizon Telescope (EHT), it has become possible to resolve the near-horizon region of astrophysical black holes. As a result, there has been…

High Energy Astrophysical Phenomena · Physics 2023-07-31 Avery E. Broderick , Kiana Salehi , Boris Georgiev

Combining asymptotically safe quantum gravity with a tensor field theory, we exhibit the first example of a theory with gravity and scalar fields in four dimensions which may realize asymptotic safety at a non-vanishing value of the scalar…

High Energy Physics - Theory · Physics 2025-01-20 Astrid Eichhorn , Razvan Gurau , Zois Gyftopoulos

Four spherically symmetric but non-asymptotically flat black hole solutions surrounded with spherical dark matter distribution perceived under the minimal length scale effect is derived via the generalized uncertainty principle. Here, the…

General Relativity and Quantum Cosmology · Physics 2023-12-08 Ali Övgün , Lemuel John F. Sese , Reggie C. Pantig

We analyze the shadow of charged stationary axially symmetric space-time (Kerr-Sen dilaton-axion black hole). This black hole is defined by a mass $M$, a spin $a$ and $r_{\alpha}=Q^{2}/M$, where $Q$ is the electric charge. Shadows are…

General Relativity and Quantum Cosmology · Physics 2016-11-01 Sara Dastan , Reza Saffari , Saheb Soroushfar

We investigate the astrophysical consequences of black holes in quadratic gravity, characterized by the parameters $S_0$, $S_2$, $m_0$ and $m_2$, in addition to the black hole mass $M$. To evaluate the physical validity of the fundamental…

General Relativity and Quantum Cosmology · Physics 2024-12-24 Somi Aktar , Niyaz Uddin Molla , Farook Rahaman , G. Mustafa

We report the existence of two exotic compact objects in the leading relativistic model of modified Newtonian dynamics, namely aether-scalar-tensor theory. This model is consistent with precision cosmology and gravitational wave constraints…

General Relativity and Quantum Cosmology · Physics 2025-06-10 Lirui Yang , Will Barker , Tobias Mistele , Amel Durakovic