When an neutrino is observed, it becomes a point particle, but it has mass. Is that mass not concentrated into a point? Why doesn't it collapse down to a micro black hole? What's the difference between a neutrino and a micro black hole of the same mass? I know it has 1/2 spin and other properties, but why? In a similar thought, what would happen if you tried the double slit experiment with micro black holes? Does relativity and QM agree in the expected result or is it too fuzzy to even lean one way or the other (blotches or interference patterns) in one or both theories? I would expect relativity to predict no interference pattern. Would string theory provide a prediction?