Test of the equivalence principle from neutrino oscillation experiments

Abstract

We consider the hypothesis that neutrino oscillation data can be explained if the gravitational couplings of (massless or degenerate mass) neutrinos are flavor nondiagonal, in violation of the equivalence principle. We analyze the various neutrino oscillation laboratory experimental data including the recent LSND observations to constrain the relevant parameter space. We find (under the hypothesis that gravity couples to matter and antimatter in the same way) that there is no allowed region of parameter space which can explain the existing data, implying that the LSND result cannot be explained by oscillations of degenerate-mass neutrinos due to equivalence principle violations.