Neutrino Oscillations as a Probe of Dark Energy

We consider a class of theories in which neutrino masses depend significantly on environment, as a result of interactions with the dark sector. Such theories of mass varying neutrinos (MaVaNs) were recently introduced to explain the origin of the cosmological dark energy density and why its magnitude is apparently coincidental with that of neutrino mass splittings. In this Letter we argue that in such theories neutrinos can exhibit different masses in matter and in vacuum, dramatically affecting neutrino oscillations. Both long and short baseline experiments are essential to test for these interactions. As an example of modifications to the standard picture, we consider simple models which may simultaneously account for the LSND anomaly, KamLAND, K2K and studies of solar and atmospheric neutrinos, while providing motivation to continue to search for neutrino oscillations in short baseline experiments such as BooNE.