> You set up a photodetector around each slit, and measure when a particle passes through it. [...No interference happens...] > This is weird! No, it's not.

> You set up a photodetector around each slit, and measure when a particle passes through it. [...No interference happens...] > This is weird! No, it's not. You made that particle's wave function collide with the huge wave function of a photodetector, of course it's going mess up the wave of the particle itself.