Gravitational coupling of neutrinos in a medium
  In a medium that contains electrons but not the other charged leptons, such as normal matter, the gravitational interactions of neutrinos are not the same for all the neutrino flavors. We calculate the leading order matter-induced corrections to the neutrino gravitational interactions in such a medium and consider some of their physical implications. 
Jose F. Nieves (University of Puerto Rico), Palash B. Pal (Saha   Institute, Calcutta)