arXiv subjects

Mohammad Ali S. Afshar

Publications and source records attributed to Mohammad Ali S. Afshar.

38 records · Page 3Linked to original sources

arXiv2023

Bardeen Black Hole Thermodynamics from Topological Perspective

In this paper, we use the generalized off-shell Helmholtz free energy method to explore the thermodynamic properties of Bardeen black holes (BD BHs) from a topological perspective based on Duan's topological current $ϕ$-mapping. We consider various structures of BD BHs, including regular BD-AdS BHs, BD-AdS BHs in Kiselev's model of quintessence, BD BHs in massive gravity (MG), and BD BHs in 4D Einstein-Gauss-Bonnet (EGB) gravity. We demonstrate that these BHs have one topological classification (TC), i.e., TC is +1 for all BHs considered, and the addition of MG or GB terms, etc., does not change the topological numbers.

hep-th↗

arXiv2023

Can black holes cause cosmic expansion?

Recently, it was shown in [1] that black holes are the source of dark energy. In [2-5], the truth or falsity of this concept has been discussed. We briefly state the arguments raised in each of these papers, but our main goal is not to accept or reject these debates. Rather, in this note, we show that black holes in specific structures, such as the Reissner-Nordstrom (R-N) black hole in the presence of quintessence, string cloud, and perfect fluid, can produce a repulsive force with respect to the weak gravity conjecture mechanism that overcomes the gravitational force.\textit{ We discuss these repulsions forces in a population of black holes of the same family can be considered as an auxiliary factor (albeit a weak factor) for the expansion of the universe}.

gr-qc↗