Particle Physics in Curved Spacetime and Dark Matter

We review recent results showing that, within the framework of quantum field theory in curved spacetime, the semiclassical energy-momentum tensor of the neutrino flavor vacuum fulfills the equation of state of dust and cold dark matter. By considering spherically symmetric spacetimes in the weak field approximation, the flavor vacuum is shown to contribute as a Yukawa correction to the Newtonian potential. We discuss how this modified potential provides a mechanism to account for the flat rotation curves of spiral galaxies. In this perspective, neutrino mixing is presented as a viable contributing factor to the dark matter content of the universe.