arXiv subjects

Moslem Shafiee

Publications and source records attributed to Moslem Shafiee.

3 recordsLinked to original sources

arXiv2026

Hawking radiation from a semi-classical Schwarzschild black hole

This study investigates the evaporation process of a Schwarzschild black hole, incorporating quantum corrections arising from conformal anomaly and vacuum polarization. We show that these quantum corrections significantly modify the Hawking radiation and thermodynamic behavior of the black hole. In particular, the Hawking temperature reaches a maximum value and subsequently decreases as the black hole loses mass, eventually vanishing in the extremal limit. The evaporation process therefore approaches an extremal remnant configuration with zero Hawking temperature. Furthermore, we demonstrate that the black hole entropy receives logarithmic corrections due to the modified thermodynamic structure. Hawking radiation is also analyzed using the Parikh-Wilczek tunneling method, which confirms the consistency of the obtained thermodynamic behavior within the quantum-corrected framework.

hep-th↗

arXiv2022

Quantum vacuum effects on the formation of black holes

We study the backreaction of quantum fields induced through the vacuum polarization and the conformal anomaly on the collapse of a thin shell of dust. It is shown that the final fate of the collapse process depends on the physical properties of the shell, including its rest and gravitational masses. Investigating the conditions for the formation of black holes, we notice that quantum effects modify the geometry and structure of Schwarzschild space-time in such a way that black holes have two horizons, an inner and an outer horizon. If the gravitational mass of the shell is about that of an ordinary star, then in most cases, the semi-classical collapse will terminate in a singularity, and in general, quantum fluctuations are not strong enough to prevent the creation of the singularity. Although under certain conditions, it is possible to form a non-singular black hole, i.e., a regular black hole. In this way, the collapse stops at a radius much larger than the Planck length below the inner horizon, and the shell bounces and starts an expansion.

hep-th↗

arXiv2021

Correction to black hole radiation due to pair annihilation

We consider the emission of charged scalar particles from a Schwarzschild black hole. It is shown that these particles can interact with each other through pair annihilation, and as a result, produce photons. These photons make a correction to the spectrum of photons that are directly emitted from the black hole. By solving field equations using the WKB approximation, the pair annihilation rate is taken into account for the most probable case, i.e., the first order, and therefore the correction will be of the order of $e^2$. Considering this scenario, we show that most interactions take place near the event horizon of the black hole, yet the number of interactions is not large enough to make a remarkable modification in the radiation spectrum of particles. These results refute the claims that interactions cause immense changes in the Hawking radiation spectrum of a black hole.

gr-qc↗