Atom and its Quantum Mirror Image

Standing in front of a mirror, we can easily tell apart ourselves from our mirror image. The mirror does not affect our motion in any way. For quantum particles, this is much more complicated. In a spectacular experiment in the labs of the Heidelberg University, a group of physicists from Heidelberg Unversity, together with colleagues at TU Munich and TU Vienna extended a gedankenexperiment by Einstein and managed to blur the distinction between a particle and its mirror image. The results of this experiment have now been published in the journal "Nature Physics". Emitted Light, Recoiling Atom - When an atom emits light (i.e. a photon) into a particular direction, it recoils in the opposite direction.