Mass is mass is mass. Physicists have three different definitions of mass, all thought to be equivalent. Measurements of the distance between Earth and the moon confirm that two of those masses are ...

The result from CERN confirms expectations, but it's the first time gravity’s effect on the stuff has actually been tested. Reading time 3 minutes In the 95 years we’ve known about antimatter, ...

A test performed on antihydrogen atoms has shown that gravity acts on matter and antimatter in a similar way. The experimental feat is the latest in efforts to probe the crossover between theories of ...

I've been trying to explain quantum physics, forces, relativity, and space-time to my kid and we had a question that I'm finding difficult to find a solid answer to. Background you can skip if you ...