Neutrino Mixing, Flavor Vacuum and Galactic Rotation Curves

We report on the connection between neutrino mixing and dark matter within the framework of quantum field theory in curved spacetime. The flavor vacuum exhibits a condensate structure whose semiclassical energy-momentum tensor acquires a perfect-fluid form with zero pressure. In static spherically symmetric spacetimes, and within the weak field approximation, the resulting energy density induces a Yukawa-like correction to the Newtonian gravitational potential. We review the derivation of the flavor-vacuum energy-momentum tensor and the modified gravitational potential, summarizing their phenomenological implications for galactic rotation curves and the baryonic Tully-Fisher relation [1].