2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/5361A brief note on the time variation of the fine structure constant $α_{em}$; it is shown that such a variation should violate mass-energy conservation in the absence of proton decay.Latex2e document. 3 pagesAstrophysicsTime variation of the fine structure constant and mass-energy conservationtext