Of potential interest:
Mesons violate Bell's inequality (Nov 6)
The famous Bell's inequality of quantum mechanics has been tested in a
high-energy particle physics experiment for the first time. The
inequality was violated by three standard deviations in experiments with
B mesons at the KEK laboratory in Japan - yet again confirming the
predictions of quantum theory (arxiv.org/abs/quant-ph/0310192; J. Mod.
Optics to be published). Previously most Bell's inequality experiments
have been performed with photons or ions.