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arXiv · 2210.14288

Radiant gravitational collapse with anisotropy in pressures and bulk viscosity

A. C. Mesquita·M. F. A. da Silva
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Abstract

We model a compact radiant star that undergoes gravitational collapse from a certain initial static configuration until it becomes a black hole. The star consists of a fluid with anisotropy in pressures, bulk viscosity, in addition to the radial heat flow. A solution of Einstein's field equations with temporal dependence was presented to study the dynamic evolution of physical quantities, such as the mass-energy function, the luminosity seen by an observer at infinity and the heat flow. We checked the acceptability conditions of the initial static configuration to obtain a range of mass-to-radius ratio in which the presented star model is physically reasonable. The energy conditions were analyzed for the dynamic case, in order to guarantee that the model is composed of a physically acceptable fluid within the range of the mass-to-radius ratio obtained for the static configuration or if they will be modified during the collapse

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A. C. Mesquita, M. F. A. da Silva. 2022-10-25. Radiant gravitational collapse with anisotropy in pressures and bulk viscosity. https://doi.org/10.1007/s10714-023-03098-4

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