From the Editor
Search and Discovery
After 20 seconds in an optical lattice, the gravitational potential-energy difference between two wavepackets separated by micrometers generates megaradians of phase.
Issues and Events
A little-used nuclear fuel may be the foot in the door for a US company hoping to snag a far bigger prize.
Relying on students to rate professors is convenient, cheap, and problematic.
The elements’ electronic configurations help explain why the rare earths are key ingredients in dozens of technological products—cell phones, computer hard drives, and lasers among them.