2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/34690As we showed in a preceding arXiv:gr-qc Einstein equations, conveniently written, provide the more orthodox and simple description of cosmological models with a time dependent speed of light $c$. We derive here the concomitant dependence of the electric permittivity $ε$, the magnetic permeability $μ$, the unit of charge $e$, Plank's constant $h$, under the assumption of the constancy of the fine structure constant $α$, and the masses of elementary particles $m$. As a consequence of these concomitant dependences on time they remain constant their ratios $e/m$ as well as their Compton wave length $λ_c$ and their classical radius $r_0$.Latex, 11 pagesGeneral Relativity and Quantum Cosmologytext