Editing C-symmetry (section)

==Combination of charge and parity reversal==
It was believed for some time that C-symmetry could be combined with the [[parity (physics)|parity]]-inversion transformation (see [[P-symmetry]]) to preserve a combined [[CP-symmetry]]. However, violations of this symmetry have been identified in the weak interactions (particularly in the [[kaon]]s and B [[meson]]s). In the Standard Model, this [[CP violation]] is due to a single phase in the [[CKM matrix]]. If CP is combined with time reversal ([[T-symmetry]]), the resulting [[CPT-symmetry]] can be shown using only the [[Wightman axioms]] to be universally obeyed.