1 Feynman's double-slit experiment gets a makeover Mar 14, 2013 Electrons travelling through two slits and a single slit Physicists in the US and Canada say that they have done the best job yet of realizing Richard Feynman's famous thought experiment about how single electrons pass through two slits. Although the researchers are not the first to recreate the experiment in the lab, they say that their incarnation best captures the essence of the original exercise. Feynman originally outlined his thought experiment in volume three of his famous series The Feynman Lectures on Physicsas a way of illustrating wave–particle duality in quantum mechanics. In the book, he invites the reader to imagine firing individual electrons through two slits and then marking the position where each electron strikes a screen behind the slits. After many electrons have passed through the slits, the marks on the screen will comprise a diffraction pattern –illustrating the wave-like behaviour of each electron. But if one were to cover up one of the slits so that each electron could only pass through the other slit, the diffraction pattern would not appear –showing that each electron does indeed travel through both slits.