2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/41418This is a pedagogical review of some selected topics of CP and T violation in the decays of K mesons. Diagonalization of the quark mass matrix and the emergence of the complex phase in both the standard and the left--right symmetric models is considered in great detail. Prominence is given to a correct definition of the CP-violating quantities: $ε, ε'$ {\it etc.} (with due regard for the Wu--Yang phase convention) and to formulation of the time-reversal invariance criterion in the elementary particle physics. A particular attention has been concentrated on theoretical evaluation of the parameters $ε$ and $ε'$ and the CP- and T-violating asymmetries in the decays $K \to μνγ$ and $K \to 3π$.28 pages, 11 figures; a talk presented at the 24 Int. Workshop on High-Energy Physics and Field Theory, Protvino, 27--29 June 2001High Energy Physics - Phenomenologytext