Parity and philosophical takeaways

1:06:18actually talk about certain experiments that you could do, >> okay, >> to maybe find out if something if beta decay is different in the mirror world. >> Yes. >> Okay. Everything else is the same. But beta decay is something that no one's actually bothered to check. Okay. They they contact Chen Chung Wu >> who is um an experimental physicist at Colombia. She's one of the great great experimental physicists of the 20th century and she was basically the expert in the entire world about beta decay and beta decay spectroscopy. So they're like there's one person that we can go to and

1:06:59it's um Chian Jang Woo. >> Um they proposed this they proposed this idea this like I want to check if this thing is symmetric. So Woo comes up with this ingenious experiment. Okay. >> Okay. Here's what she does. She gets cobalt 60, which is an isotope of cobalt. Okay. It's got 60 um neutrons and protons in its nucleus. And what they're going to do is they're going to wait for the cobalt 60 to decay into nickel 60. So notice the atomic number has remained the same which means what's happened is a neutron has turned into a proton. >> A neutron turning into a proton that's a

1:07:40neutral charge going into a positive charge which means it has to release a negative charge by the negative charge. >> Exactly. By the conservation of charge the charges before and have to remain the same. So if I've created a positive charge and I started at zero I need to create a negative charge to balance it out. >> Mhm. So this is a process of beta decay. Okay, this is something that has to do with the weak nuclear force. Okay, the question is is the electron that gets spit out, does it have a preferred orientation? >> This goes back to our right-handedness, left-handedness. >> Exactly. >> Does it does the electron that gets spit out, does it have a way of only

1:08:23preferring left or right or one of the other? >> Yeah, >> that's the question. It's a very simple experiment, right? That's and this is the genius of Woo. I mean, the the experiment sounds simple. It's insane, right? You got to you got to get these cobalt 60 atoms. Then you got to cool it down to near absolute zero because you don't want the cobalt 60 to be, right? You want to tell which way the electron is moving. So, you got to columnate all of the cobalt 60 so that it's all oriented in the same direction. The cobalt 60 itself has a spin on its own, right? So you want all of the cobalt 60 atoms to be oriented in the same direction which means you got to cool [snorts] everything down to near absolute zero. This is something like 10 millich keelvin which is like difficult

1:09:04even now but back then like she had to do it at the um NIST the NIST offices in Washington DC because they were experts at making really really cold things. So she actually told them this was in um December of 1957. Okay. Or 1956, actually, December of 1956, she goes down to Washington DC and she sets up this apparatus. She wants to do it fast because she knows this is going to be big. So she's like, "No, I I I am Lady Woo. I am in charge of beta decay everywhere around the world. I'm going to do this." So she gets Cobalt 60. She cools it down, puts a magnetic field on it so that all of the Cobalt 60 atoms, let's say, are oriented in this

1:09:45direction. Let's say away from me. So they're they're they're pointing in this direction and she waits for the electrons to come out right during this decay. Now here is the critical thing. Okay, there's two scenarios that could happen. The cobalt 60 is oriented in one direction. The electron could go forward