Scientists have made the first experimental observation of matter wave diffraction in a short-lived electron-positron atom.

Optical interference is not only a fundamental phenomenon that has enabled new theories of light to be derived, but it has also been used in interferometry for the measurement of small displacements, ...

In a first, scientists have shown that they can send light through “slits in time” in time. The new experiment is a twist on a 220-year-old demonstration, in which light shines through two slits in a ...

Two of the forefathers of quantum theory, Albert Einstein and Niels Bohr, had a famous argument over whether light is a wave ...

Can we turn back time? Ask a savvy physicist, and the answer will be “it depends.” Schemes for retrograde time travel abound but usually involve irreconcilable paradoxes and rely on outlandish ...