Actually, looking at the diagram and explanation of the experiment posted at I think Saibal Mitra and the sci.physics.research poster I quoted may have misunderstood what happened in this experiment. I may have misunderstood, but it sounded as if both were arguing that the finite width of the wires could erase some of the which-path information and explain why you'd see interference at the final detectors. But the diagram seems to say that *no* interference was found at the detectors----the interference Afshar is talking about was just in the fact that no photons were scattering against the wires because they were all placed in the interference valleys. So the idea seems to be that interference is the explanation for why no photons scatter against the wires, but the focusing lens behind the wires makes sure that photons from the left slit always go to the left detector and the photons from the right slit always go to the right detector--this is the "violation of complementarity", that the photons behave like a wave in avoiding the wires but behave like particles when arriving at the detectors. I'm not sure that the notion of "complementarity" has ever been sufficiently well-defined to say that this experiment violates it though, and in any case, as long as the results of the experiment match the predictions made by the standard theory of quantum mechanics, it cannot be taken as a disproof of the Everett interpretation, since the basic idea of the Everett interpretation is to keep the standard rules for wavefunction evolution but just to drop the "collapse" idea (the projection postulate).


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