An experiment on the side of an extinct volcano in Mexico involving gamma rays is helping scientists answer a fundamental question in physics: Is the speed of light the same throughout the universe?

The famous double-slit experiment, which demonstrated that light is both a wave and a particle, has been performed using “slits in time”. The techniques involved present a new way to manipulate light ...

Dark matter, a type of matter that does not emit, absorb, or reflect light, is predicted to account for most of the universe's mass. While theoretical predictions hint at its abundance, detecting this ...

When the massive upgrade at the Advanced Photon Source (APS) at the U.S. Department of Energy’s (DOE) Argonne National Laboratory is completed later this year, experiments at the powerful X-ray light ...

Scientists at the X-ray free-electron laser SwissFEL have realized a long-pursued experimental goal in physics: to show how electrons dance together. The technique, known as X-ray four-wave mixing, ...

Small angle X-ray scattering, or SAXS, is an experimental method where the intensity of the scattered X-rays is measured as a function of the scattering angle. The information obtained in a SAXS ...