Cassini plume chemistry and the Earth match

1:10:33terrible analogy because I'm always trying to figure out ways to think about it in my head. If you have a relay race, a 4x400, classical computers, you have to wait to hand the baton to the next runner. >> Yeah. >> But in a quantum computer, my first lap, the first runner can have like multiple >> runs >> and like whichever one happens to get there first is like and so it's like your parent >> all four just basically cheat, right? Go through the whole thing. Yeah. But just as trying to like contextualize like what the difference is when you say that a cubit can be in a superp position of both zero and one. There's not you're not waiting for the handoff in order for the next thing to do its next process.

1:11:15>> Yeah. Yeah. You can do a lot of things in parallel and and you can access a lot of computational stuff in parallel. Yeah. Yeah. It's a weak analogy but it'll work actually. Um and and at the end of the day, how a quantum algorithm works is the following. There's something that's very um famous called the shores algorithm. Okay, this is the one that all the NSA and everyone is excited about because this is the algorithm that lets you break RSA encryption. >> Okay, >> but it works like any other quantum algorithm in that here's what happens. You've got a bunch of cubits that you're going to prepare in some kind of state. Let's just say for for um argument sake, I'm going to prepare them in the zero

1:11:56state. So they're all zero. >> And then what I'm going to do is that I'm going to apply quantum gates to these guys. Okay? And what that means is I'm going to poke this cubit a one way. So it's going to maybe flip from a zero to a one or it's going to flip into halfway between 0 and a one. And then this guy's going to talk to its neighbor who's going to talk to his neighbor. And all of these quantum gates are basically pokes in some way >> of each of the bits that I have. >> The the key bottleneck is the following. Okay, my gates and my poking have to be faster than how long it takes for my cubit to forget itself. Here's what I

1:12:38mean by that. Okay. >> In a transistor, if I turn it off, it's going to stay off. >> Unless like a cosmic ray comes in and like like you know the the the some proton comes in and knocks exactly that transistor from a zero to a one. It's going to remain off and I can reliably come back and it'll remain off. This is how data works, right? Why why is my data >> or how do I store stuff, right? This this is the transistor is in the in or like whatever thing is in the zero and the one is going to be in the zero and one forever. It's not a transistor. It's solid state or whatever. But at the end of the day, I have some time horizon that is way longer than my computation.

1:13:18>> Yes. >> That I know can reliably remember if it's a zero or a one. In quantum mechanics, that's no longer the case because these cubits are made out of incredibly small technologies. Okay? And so there's a lot of forgetting that happens. I I I prepare my cubit in a zero state. For example, let's take the extreme case of an electron that's spinning in one direction and that's my zero. If it spins in the other direction, that's my one. >> Well, I need this thing to remember that it's spinning in that direction. Yep. >> But if there's a bunch of stuff around it, it's going to start poking it, right? There's a bunch of atoms and a bunch of little magnetic fields that the

1:13:58atoms create that are going to try to change the way that my electron is spinning. So if my electron is this cubit where spinning down is zero and spinning up is one and I prepare it in the down, it's not going to take very long for that electron to just get influenced by all of the stuff around it and forget that it was a zero in the first place. This is called the decoherence time. >> Okay. And one of the central challenges is one one of the central challenges in creating a workable quantum computer is to make the decoherence time way way longer than the

1:14:39algorithm time. So so this this actually