Quantum mechanics flummoxes physicists again : Nature News

Quantum mechanics flummoxes physicists again : Nature News: "To perform their experiment, Weihs and colleagues aimed a source of single photons (which, like electrons, exhibit wave–particle duality) at a mask containing various open and closed combinations of three slits. The authors fired photons repeatedly through the mask, while building a probability distribution of photons arriving on a detector beyond it. From the probabilities of each combination, they could calculate a crucial interference term, which would highlight any three-path interference."