Year: 2025
Type: article
Abstract: In this work, we investigate the particle creation rate in a dynamical (Vaidya) spacetime using Feynman's path integral formalism within the framework of the effective action approach. We examine three distinct cases involving the following mass functions, each representing dynamical geometries: (i) $m(v,r)=\ensuremath{\mu}v$, (ii) $m(v,r)=\ensuremath{\mu}v+\ensuremath{\nu}r$, and (iii) $m(v,r)=\ensuremath{\mu}v\ensuremath{-}\frac{{\ensuremath{\mu}}^{2}{v}^{2}}{2r}$, where $\ensuremath{\mu}$ and $\ensuremath{\nu}$ are positive constants that satisfy all known energy conditions. We analyze particle production rates in the region of dynamical horizons, revealing an initial high rate followed by a rapid decline in all cases. Additionally, we explore the thermodynamic properties by calculating the surface gravity and corresponding Hayward-Kodama temperatures for each scenario. Graphical representations show the variation of surface gravity over time for the three cases, offering insights into the system's thermodynamic evolution. Our research investigates the connection between background geometry and the particle creation process, placing it within the broader context of quantum field theory in curved spacetime. The nonstationary nature of Vaidya geometry is highlighted as a valuable framework for examining the dynamic aspects of particle creation. This in-depth analysis enhances our understanding of quantum processes in curved spacetime and may offer insights relevant to thermodynamics and studies of gravitational collapse.
Authors: Samit Ganguly, Narayan Banerjee, Abhijit Bhattacharyya, Goutam Manna
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4409247308