Testing the principle of equivalence by supernova neutrinos

We study the possible impact of the neutrino oscillation which could be induced by a tiny violation of equivalence principle (VEP) on the observation of neutrinos emitted from supernova driven by gravitational collapse. We show that using supernova neutrinos, one can probe very small values of VEP parameters, δ γ ≲O(10 −31) for massless or degenerated neutrinos and δ γ≲ O(10 −16)×( Δm 2/10 −5 eV 2) for massive neutrinos.