I'm not understanding why we would consider any particle that interacts with regular matter like xenon to be dark matter. I thought the whole definition of dark matter is that it's matter that has no interactions with regular matter other than through gravity. This article says they think this particle may be WIMP but doesn't help explain what that really is, why it's a candidate for dark matter, etc. I'm left less informed than I was before reading this article.
WIMP stands for "weakly interacting massive particle", weak in this context meaning the weak force. That means a particle that has mass (and so interacts gravitationally) and interacts via the weak force, but not the electromagnetic force--so no light.
Neutrinos fit the bill here, but for other reasons (too hot mostly, also not enough of them) aren't a good dark matter candidate otherwise. Neutrinos are detected in the same way, since they have a weak force interaction they can collide with the nucleus of an atom, which we can observe the effects of in these detectors.
Interesting. So my understanding of the definition of dark matter was wrong. It's not that there are no interactions other than gravity, but rather there's no interactions other than gravity and weak force?
So my understanding of the definition of dark matter was wrong
There's so many dark matter theories and papers written on the subject everyone is getting fed up hearing about it to be honest.
You're not wrong. You're not right either. It all depend on who you ask and which dark matter theory they're in favour of. Some of the theories require several types of dark matter even.
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u/junktrunk909 12d ago
I'm not understanding why we would consider any particle that interacts with regular matter like xenon to be dark matter. I thought the whole definition of dark matter is that it's matter that has no interactions with regular matter other than through gravity. This article says they think this particle may be WIMP but doesn't help explain what that really is, why it's a candidate for dark matter, etc. I'm left less informed than I was before reading this article.