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The Energy Density of a Gas of Photons Surrounding a Spherical Mass $M$ at a Non-Zero Temperature

Achilles D. Speliotopoulos
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Abstract

The equations determining the energy density $ρ$ of a gas of photons in thermodynamic equilibrium with a spherical mass $M$ at a non-zero temperature $T_s>0$ is derived from Einstein's equations. It is found that for large $r$, $ρ\sim 1/r^2$ where the proportionality constant is a {\it fundamental constant\/} and is the same for all spherical masses at all temperatures.

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Achilles D. Speliotopoulos. 1993-05-24. The Energy Density of a Gas of Photons Surrounding a Spherical Mass $M$ at a Non-Zero Temperature. https://arxiv.org/abs/hep-ph/9305302

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