2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/179164We show that the non-strange scalar $σ$ meson, as now reported in the 1996 PDG tables, is a natural consequence of crossing symmetry as well as chiral dynamics for both strong interaction low energy $ππ$ scattering and also $K \to 2π$ weak decays.Latex, 15 pagesHigh Energy Physics - Phenomenologytext