2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/196246We show that local/semilocal strings in Abelian/non-Abelian gauge theories with critical couplings always reconnect classically in collision, by using moduli space approximation. The moduli matrix formalism explicitly identifies a well-defined set of the vortex moduli parameters. Our analysis of generic geodesic motion in terms of those shows right-angle scattering in head-on collision of two vortices, which is known to give the reconnection of the strings.5 pages; v2 references added; v3 the final versionHigh Energy Physics - TheoryAstrophysicsHigh Energy Physics - Phenomenologytext