2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/49197Up to second order in alpha, vacuum electro-magnetic corrections to weak interaction induced charged particle lifetimes have been previously studied. In the laboratory, stopped muon lifetimes are measured in a condensed matter medium whose radiation impedance differs from that of the vacuum. The resulting condensed matter corrections to first order in $α$ dominate those vacuum radiative corrections (two photon loops) which are second order in alpha.RevTeX 4 pages plus one postscript figureHigh Energy Physics - Phenomenologytext