Shiraz University

output

19982026

most citedHorizon-scale tests of gravity theories and fundamental physics from the Event Horizon Telescope image of Sagittarius A

^{*}

753 citations

researchers with a paper here

Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.

collaborating institutions

Showing 2022 · gr-qcShow all

21 papers · 2 filters

gr-qc2022★ 17 cited

Superradiant energy extraction from rotating hairy Horndeski black holes

Sohan Kumar Jha, Mohsen Khodadi, Anisur Rahaman +1

Adopting the manifest of low-frequency and low mass for the scalar perturbation, we perform a semi-classical analysis of the superradiance phenomenon for a rotating hairy Horndeski…

gr-qc2022★ 26 cited

Constraining the Lorentz-Violating Bumblebee Vector Field with Big Bang Nucleosynthesis and Gravitational Baryogenesis

Mohsen Khodadi, Gaetano Lambiase, Ahmad Sheykhi

By keeping the cosmological principle i.e., an isotropic and homogeneous universe, we consider the cosmology of a vector-tensor theory of gravitation known as the \textit{bumblebee…

gr-qc2022★ 29 cited

Shadow of black hole surrounded by magnetized plasma: Axion-plasmon cloud

Mohsen Khodadi

By exploiting the extreme environment of the black hole (BH) as a potential place for axion-photon interaction, we use an axion-producing model of the magnetized plasma to study th…

gr-qc2022★ 24 cited

Holographic dark energy in modified Barrow cosmology

Ahmad Sheykhi, Maral Sahebi Hamedan

Thermodynamics-Gravity conjecture implies that there is a deep connection between the gravitational field equations and the first law of thermodynamics. Therefore, any modification…

gr-qc2022★ 23 cited

Lifetime of scalar cloud formation around a rotating regular black hole

Mohsen Khodadi, Reza Pourkhodabakhshi

Does circumventing the curvature singularity of the Kerr black hole affects the timescale of the scalar cloud formation around it? By definition, the scalar cloud, forms a gravitat…

gr-qc2022★ 51 cited

Modified cosmology through Barrow entropy

Ahmad Sheykhi

We investigate the cosmological consequences of the modified Friedmann equations when the entropy associated with the apparent horizon, given by Barrow entropy, $S \sim A^{1 + δ /2}$ ,…

gr-qc2022★ 3 cited

Gauss-Bonnet black holes in a special anisotropic scaling spacetime

S. Mahmoudi, Kh. Jafarzade, S. H. Hendi

Inspired by the Lifshitz gravity as a theory with anisotropic scaling behavior, we suggest a new $(n + 1) -$ dimensional metric in which the time and spatial coordinates scale anisotro…

gr-qc2022★ 34 cited

Entropic corrections to Friedmann equations and bouncing universe due to the zero-point length

Kimet Jusufi, Ahmad Sheykhi

We employ Verlinde's entropic force scenario to extract the modified Friedmann equations by taking into account the zero-point length correction to the gravitational potential. Sta…

gr-qc2022★ 1 cited

On observational signatures of multi-fractional theory

Mahnaz Asghari, Ahmad Sheykhi

We study the multi-fractional theory with $q$ -derivatives, where the multi-fractional measure is considered to be in the time direction. The evolution of power spectra and also the…

gr-qc2022★ 23 cited

Dark Energy Star in Gravity's Rainbow

A. Bagheri Tudeshki, G. H. Bordbar, B. Eslam Panah

The concept of dark energy can be a candidate for preventing the gravitational collapse of compact objects to singularities. According to the usefulness of gravity's rainbow in UV…

gr-qc2022★ 18 cited

Analytically Approximation Solution to Einstein-Cubic Gravity

S. N. Sajadi, S. H. Hendi

In this work, we introduce an analytical approximate black hole solution in Einstein-Cubic gravity. To obtain complete solutions, we construct the near horizon and asymptotic solut…

gr-qc2022★ 4 cited

Charged Black Holes in Einsteinian Quartic Gravity

S. N. Sajadi, Leila Shahkarami, Farid Charmchi +1

In this paper, we studied Einsteinian quartic gravity minimally coupled to electrodynamics in four dimensions. First, by variation action, we obtain the field equations, and by int…

gr-qc2022★ 71 cited

Probing the Lorentz Symmetry Violation Using the First Image of Sagittarius A*: Constraints on Standard-Model Extension Coefficients

Mohsen Khodadi, Gaetano Lambiase

Thanks to unparalleled near-horizon images of the shadows of Messier 87* (M87*) and Sagittarius A* (Sgr A*) delivered by the Event Horizon Telescope (EHT), two amazing windows open…

gr-qc2022★ 36 cited

Black holes in dRGT massive gravity with the signature of EHT observations of M87*

S. H. Hendi, Kh. Jafarzade, B. Eslam Panah

The recent Event Horizon Telescope (EHT) observations of the M87* have led to a surge of interest in studying the shadow of black holes. Besides, investigation of time evolution an…

gr-qc2022★ 12 cited

Observational constraints on the fractal cosmology

Mahnaz Asghari, Ahmad Sheykhi

In this paper, we explore a fractal model of the universe proposed by Calcagni [JHEP{\bf03}(2010)120] for a power-counting renormalizable field theory living in a fractal spacetime…

gr-qc2022★ 753 cited

Horizon-scale tests of gravity theories and fundamental physics from the Event Horizon Telescope image of Sagittarius A $^{*}$

Sunny Vagnozzi, Rittick Roy, Yu-Dai Tsai +12

Horizon-scale images of black holes (BHs) and their shadows have opened an unprecedented window onto tests of gravity and fundamental physics in the strong-field regime. We conside…

gr-qc2022★ 47 cited

Growth of Perturbations in Tsallis and Barrow Cosmology

Bita Farsi, Ahmad Sheykhi

We disclose the effects of the entropic corrections to the Friedmann equations on the growth of perturbations in the early stages of the universe. We consider two types of correcti…

gr-qc2022★ 9 cited

Thermodynamic stability of a new three dimensional regular black hole

S. H. Hendi, S. Hajkhalili, S. Mahmoudi

A new model of the regular black hole in $(2 + 1) -$ dimensions is introduced by considering an appropriate matter field as the energy-momentum tensor. First, we propose a novel model…

gr-qc2022★ 30 cited

Quasinormal modes of self-dual black holes in loop quantum gravity

Mehrab Momennia

We study the evolution of a test scalar field on the background geometry of a regular loop quantum black hole (LQBH) characterized by two loop quantum gravity (LQG) correction para…

gr-qc2022★ 13 cited

Structure formation in mimetic gravity