AMA | September 2024

5892.198 - 5915.045 Sean Carroll

Why is the CP symmetry respected by the strong interactions but not the weak interactions? And axions are part of an explanation for that. So you like that. You like it when the particle explains something else. And even though axions don't necessarily have the right density to be the dark matter, you can give them the right density to be the dark matter without too much effort.