It is easy to construct classical two-state systems illustrating the behavior of the short-lived and long-lived neutral K mesons in the limit of CP conservation. The emulation of CP violation is more tricky, but is provided by the two-dimensional motion of a Foucault pendulum. Analogies are drawn between the pendulum and observables in neutral kaon decays. An emulation of CP and CPT violation using electric circuits is also discussed.
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