Result: proton radius ~0.841 fm (puzzle resolved)

1:32:30>> The blue little star fighter that you see there. >> Yeah. Yeah. In the middle. >> In the middle. >> Yeah. >> That is their measurement. 0.84. Okay. >> One. >> Okay. >> It is in line with their muon measurement that they took 16 years ago. >> So the 87 I think it was >> the 0.87 that's all these other >> things over to the right. >> Yeah. >> That is wrong. >> You are the weakest link. Goodbye. >> Yep. Yeah. So so they corroborated that measurement. The muonic hydrogen is the same as the normal hydrogen. The true size of the proton is 0.84. 84. And there is no new physics, at least in

1:33:12terms of the difference between the muon and the electron. They are indeed the same up to this >> significance. >> Mhm. >> Mhm. >> For all intents and purposes, the only thing that is different between the muon and the electron is their mass. >> Is the mass. >> That's it. >> That's it. And what this also means then is that the theorists have to go back to the wood shop, woodshed, and work on it. >> Yeah. They're going to they they need to figure out what else to try. >> Right. Right. Right? Because they were they were I I bet you there were tons of theorists that were really hoping that this measurement was not going to fall within that air bar, right? That that that the muon was going to be here, the electron was going to be here, and they'd be like, "Oh, I I got a theory for why they're right." [laughter]

1:33:54>> Turns out they're not. >> This is okay. This is actually a really great story around understanding the refinement that goes through the scientific process on something like the size of a proton. like why it's incredibly difficult. >> Yeah. >> Uh like fundamentally because it's so small like we can't just image it the way we normally would. Yeah. And so we have to go through this process of >> understanding like how these things interact because how they interact creates these derivative variables that we can measure. that electron piece that we just talked about. And then you can sort of now back calculate

1:34:35what you're looking for because you actually have a strong understanding of these other uh aspects of physics and the relationship between these different moving parts. And again, this tension between theory and experiment uh uh and the back and forth and sort of it's it's sort of like a it's sort of like a this it's it's like a dance, right? Uh where both influence and and counterargue each other at different periods in time. However, the theorists did not win this one. No. >> Um I'm sorry. I'm sorry to say. Yeah. >> Uh maybe next time. >> Maybe next time. Probably. I mean, this maybe is this why they're always looking at string theory cuz then they the experimentalists can't >> Yeah, cuz on string theory [laughter]

1:35:16they're just like, "Oh, well, you I need like 10 more decimals on your measure and just keep going. >> Let's keep going." >> To to really validate my theory or not. But like jokes aside, I mean, you know, it seems like a relatively boring thing to talk about just the size of the proton, but the techniques and the the fact that this closed that door, >> right, >> on there being some new physics. >> Mhm. >> We don't have to think about that anymore. >> Right. Right. >> Right. Like leptton universality is a thing. The muon and the electron are the same except for mass. Yes. >> Now we can worry about other stuff. Right. You can put constraints on exotic particles like there's zero anomalous

1:35:59deviation from quantum electronamics rules, >> right? So like a bunch of other stuff about dark matter like oh there's this dark sector that maybe does this. Well, if that particular way of thinking about dark matter has a different measurement, >> it's wrong. >> Right. Right. >> Falsifiability is everything when it comes to physics. Right. >> That's actually I didn't think about that. What you're saying is uh this experimental result can now inform research areas that are not about uh like measurements of these subatomic particles and things like that. >> But there's overlap conceptually or architecturally >> that if you were basing your dark matter

1:36:40model off of the original 0087 theoretical framework. >> Sorry. >> Sorry. [laughter] Yeah. Gotta love sigh. That's a good that is a very good very technical story. >> Yeah. >> Um but really again the the the fun to me is in the journey and the process. >> Yeah. >> Um not simply the result cuz like you said the result. Okay. The size of the proton. Great. >> Um >> but all of those new techniques again also are not isolated to just this specific research question. Uh fantastic. That was uh the sort of physics story on the proton size. We have this out of Maxplank Institute and

1:37:21it was in uh quantum op for quantum optics in nature. Uh I just I I'll ask you like that one. >> I'll ask you questions off here about that one because there's there's a couple more I have. We are going to go ahead and move into our last story which is uh a medicine story about ALS. Um,