  We review the application of the Wigner-Weisskopf model for the neutral K
meson system in the resolvent formalism. The Wigner-Weisskopf model is not
equivalent to the Lee-Oehme-Yang-Wu formulation (which provides an accurate
representation of the data).
  The residues in the pole approximation in the Wigner-Weisskopf model are not
orthogonal, leading to additional interference terms in the $K_S-K_L 2\pi$
channel. We show that these terms would be detectable experimentally in the
decay pattern of the beam emitted from a regenerator if the Wigner-Weisskopf
theory were correct. The consistency of the data with the Lee-Oehme-Yang-Wu
formulation appears to rule out the applicability of the Wigner-Weisskopf
theory to the problem of neutral K meson decay.
