According to Quantum Mechanics, a pair of particles created in any interaction exhibits EPR type of non-local correlation. In 1964, CERN physicist J.S. Bell put the non-locality in a testable form, the so-called Bell Inequality. It has since been tested with polarization in photons and spin in atoms but never with particle-antiparticle in elementary massive particles. In particle physics, both Φ → K0 Kbar0 and Υ(4S) → B0Bbar0 exhibit the same EPR non-local correlation. In this talk, I will discuss the similarities and differences of these decays with the spin 1/2 and photon system. I will then discuss the possibility of testing Bell Inequality. Finally, the preliminary result of violation of Bell Inequality using semileptonic B0 decays at BELLE experiment in KEK will be presented.
