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arXiv · 2509.00899

Inverted equation of state and general approach to vacuum-like configurations

O. B. Zaslavskii
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Abstract

We consider spherically symmetric static black hole configurations that obey the vacuum equation of state: $p_{r}=-\rho $, where $p_{r}$ is the radial pressure, $\rho $ being energy density. We find in a closed form the metric for an arbitrary equation of state for tangential pressure $p_{\theta }(\rho )$. The corresponding formulas enable us to embrace compact Schwarzschild-like configurations and dispersed systems. They include metrics with a regular center and singular ones. In a particular case, the metric of the Kiselev black hole is reproduced.

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O. B. Zaslavskii. 2025-08-31. Inverted equation of state and general approach to vacuum-like configurations. https://arxiv.org/abs/2509.00899

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