2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/93849We propose that the quantum vacuum may be considered as a gas of virtual photons which carry a non-vanishing linear momentum as well as a non-vanishing energy. We study, in particular, the Casimir effect in order to show that these virtual photons should satisfy a Fermi-Dirac statistics, which implies a non-zero temperature of the vacuum state.3 pages, revtex, no figures, 9 references. This work is a new version of a paper submitted for publication in a major journal of physicsQuantum Physicstext