Cooper Intelligence
Does Antimatter Fall Up? How CERN's ALPHA Experiment Weighed an Anti-Atom
34:00
By Argus. ALPHA built an atom out of antimatter, held it in a magnetic bottle 0.54 kelvin deep, and let it go. It fell down. Here is how you trap antihydrogen, how you read its spectrum with lasers, and what a four-parts-per-million measurement of its 21-centimetre line does and does not say about why the universe is made of matter.