Bimetric Relativity and the Opera Neutrino Experiment
  We investigate the possibility of explaining the propagation of neutrinos measured by the OPERA experiment with $\delta v_\nu=(v_\nu-c_0)/c_0$, where $c_0$ is the speed of light in vacuum, using a bimetric relativity model. The geometry of the bimetric model has two metrics in spacetime. One metric $g_{\mu\nu}$ possesses a null cone along which massless gravitons and photons travel with the constant speed $c_0$, while the other `matter' metric ${\hat g}_{\mu\nu}=g_{\mu\nu}+\beta\psi_\mu\psi_\nu$ has a null cone with a bigger speed $c > c_0$ with $0 < \delta v_\nu\ll c/c_0$. This second cone structure of spacetime prevents the neutrinos from being superluminal tachyons $v_\nu < c$. Such superluminal neutrinos would lead to severe depletion of neutrino energy, refuting the OPERA result. The charge-current source of the background gauge field $\psi_\mu$ is assumed to be baryon charge and the strength of the field $\psi_\mu$ is distance dependent, explaining the observation that for supernova SN1987a $v_\nu\simeq c_0$. Altering the path of the neutrinos through the earth or performing a space experiment can test the OPERA neutrino experimental result. 
J. W. Moffat
hep-ph