In a groundbreaking discovery, physicists have for the first time observed individual free-range atoms interacting in free space, confirming a quantum mechanical theory proposed over a century ago.

The hero is regular matter, which is everything we can see around us. Antimatter is the mirror-image explosive twin that scientists understand well but can barely find. And dark matter is the ...

Two huge metal rings, each more than two miles around. Gold ions smashing together at more than 99.99 percent the speed of ...