One of the most basic laws of quantum mechanics is that a system can be in more than one state -- it can exist in multiple realities -- at once. This phenomenon, known as the superposition principle, ...

Physicists have proposed an entirely new way to test the quantum superposition principle—the idea that a quantum object can exist in multiple states at the same time. The new test is based on ...

Three's company: interference patterns for one to four slits (expand for full image) A group of physicists in Austria has directed a beam of large molecules at a series of extremely narrow slits to ...