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Can you hear me now? Great.

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Okay, so.

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Today, I don't do very much talking.

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You guys talk and all of the order that's in that was on piaza. Let me just actually.

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See, if I can pull up a page that had.

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There in order.

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3rd.

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So, Connor 1st and G, Hong Kong David. So he sent me a video which I.

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In case of hardware problems John Rawlinson.

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Honor Macallan into sorry and then David Cohen gave us.

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So, and given that we have our and.

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20 minutes give or take, I'm suggesting 9 or 10 minutes for the single person.

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Talk, and perhaps for 15 minutes give or take.

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Or the to person talk.

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And I'm not going to electrify your chair if you go over by a minute.

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And so I'm not going to complain if you go under by a minute or 2, but say.

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You know, stop talking if you're a single person in 9 minutes or so.

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And 2 people go somewhat longer.

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Okay, so you can.

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If Connor.

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Is on line and let us see if it works.

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You have the floor can you see my screen? Yes, I can see your screen and I can also hear you.

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Okay.

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So, my name is Connie Gloucester, and I did my attention, my presentation on shooting your cat.

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Um, so the experiment is basically it's a thought experiment or paradox that.

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Was about superposition and so the experiment, um, started, um, with.

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The idea is that cat gets put in a steel box and within this deal box is a Geiger counter and in the got your counter, there's some radioactive material.

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And it has a 50, 50 chance of decaying to not the king after an hour.

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If it decays, it triggers a series of events that causes a hammer to fall and break a flask of.

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Hydro acid, which would then kill the cat.

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But where the paradox arises is.

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After an hour, we don't know whether the cat is or alive or dead, which puts it in a state of superposition.

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So, it's got a 50% chance probability of being dead and 50% of being alive.

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Which brings up questions on, like, when does a system become determinant?

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Um, which would be when you measure it, but you could also think of it. How.

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Do you look at it? Do you look at the cat as the observer, or you look at it as the catch? Just another component within the system.

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And these questions come up when dealing with the experiment.

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The actually the, the cat being the observer is a variation of the experiment, which I will talk about later.

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Um, and so a little history.

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About the experiment was, it was devised by, uh, Irwin.

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In 1935 after a discussion with Albert Einstein.

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And the discussion was about his article that he published.

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And that article was about the counterintuitive this of superposition.

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And so I had actually, 1st suggested using gunpowder instead of acid.

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Which would have been an interesting take on the whole experiment.

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Because it would have added a sound component, but then there's also.

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But the most common version is actually called the Copenhagen interpretation, which is.

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The variant where I'll go to the next slide, which is the variant where.

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You're dealing with the superposition of the States, so.

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After 1 hour, you physically observe the box to see whether the cat is alive or dead and since it's in a state of superposition, it either converges to being dead or live after you view it.

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So, it's a very straightforward take on.

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The paradox is, that's why it's the most widely known 1, but there's also 2 other common ones. The many worlds interpretation.

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And then actually, the quantum suicide variation, which.

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Takes an account both the Copenhagen and the many worlds versions.

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And so the many world's versions is.

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It still starts and you look at it as a state of superposition.

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When it's unknown after an hour, when you observe it.

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Um, it splits and so you have.

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1 world where you observe the state.

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Reserve the cat, and it was dead, and you have 1 world where you observed the cat, and it was alive.

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This is this idea brings brings about the coherence.

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Which doesn't tangles the 2 particles.

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Are the 2 States after you view them.

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And then you could think of it as entangling the, the observer to that state that was viewed.

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So, it kind of shifts everything that you were looking at.

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And this ties into the quantum suicide variation, because.

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The quantum suicide variation is the 1 where you are the cat inside the box.

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Where, after 1 hour, you have a chance of being alive, or you have a chance of being dead.

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And so if you use the Copenhagen interpretation and apply it to the quantum, apply it to you, being the observer inside the box.

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After each iteration, so after every hour, if you view it.

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Your chances of surviving decrease towards 0.

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Which is great, but.

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If you use the many world's interpretation, you end up.

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Having a quantum necessity to survive and.

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So, after every iteration, you always have.

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1 world where you are alive, and that will always be the case.

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Because the probability isn't going to go straight to 0T like, it might in the Copenhagen interpretation.

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And this brings up an idea of.

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Quantum immortality, which is a different topic altogether, so I didn't go into it, but.

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It is another interesting thing you could look into, um.

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There are 3 other variations that I had found, which.

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Weren't as popular, but so I didn't go into explaining them, which is the, in some way. Um.

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Interpretation the relation interpretation, the transactional interpretation.

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I'm going to instead talk about.

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It's called the witness friend and.

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This is the, it's a kind of it's another variation.

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But instead of having 1 person, you have 2 people.

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So, you have 1 person inside of a laboratory with the whole cat experiment.

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And this usually uses the Copenhagen interpretation.

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But there's also a variation for many worlds interpretation.

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But using the Copenhagen interpretation, you put the cat.

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Or you put the trainers cat experiment inside a room.

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With a friend and observer, you are outside of the room somewhere else.

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And so it then puts a system inside of a system.

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So, you're after an hour, your friend observes the cat.

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It sees out of the cast dead or alive and then your friend tells you.

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You don't know whether the cat is alive or dead until your friend tells you.

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But but this is where the questions arise with this problem with this paradox.

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Do the States converge the, the States converge when your friend looks at it?

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Or, did the States converge when you look at it? And.

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This brings up a ton of questions because what happens if you apply the many worlds interpretation? What happens if you apply be.

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Um, any number of variations.

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Because how do you know when the state truly converges.

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And this brought up a ton of arguments on how to handle it.

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And the main argument was, how do you define consciousness.

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And which was an extremely philosophical debate on.

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Everybody's personal point of view on is the person inside the box considered to be the conscious observer.

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Or is the person inside the laboratory makes the 1st observation to that the conscious observer, or is the.

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Wagner, who is outside of the box who hears from the friend.

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And this idea created.

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A lot of debate with how to, to take this experiment further.

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But I thought it was another if it was just a very interesting.

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A topic, or an interesting point of view on.

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How to handle superposition and how to handle.

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The, I guess measurement observe ability.

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Decision and so this is actually it was as far as I went. So, I don't know. Does anyone have any questions.

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Thank you that time for a question.

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I'll ask a quick 1. has there been any since the 19 thirties and so on.

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Pretty much there hasn't been a ton there. There's been papers being published on different perspectives.

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Um, but nothing concrete. I know I had actually done a different I started doing a different topic 1st before I got chosen.

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Um, so I know more experiments are being done with when it comes to physical hardware.

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But with the paradox, and the more conceptual aspects point of views have.

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For most of the opinions have been already written about and already been published. Okay. Well, thank you.

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So.

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Next thought jihad, Hong bottom crypto.

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Let's learn about that. All right. Can you hear me.

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Yes, I can hear you. I can't see you.

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Oh, uh, would be because my camera's not on.

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Um, my partner is, uh, Nick Murphy. Oh, thank you.

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Yeah, no problem. Yeah. Can you hear me as well?

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Yes, I can hear you Nick also. Um, I cannot see either of you.

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I just turned on my camera. Okay. Okay. Now I can see you. Yes. Cool. Okay.

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All right, let me bring back on the screen. Yeah, I know he's putting up the presentation.

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Okay all right beautiful. Can see it.

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All right, we just move all of these things out of the way.

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There you all right.

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Quite visible. All right. Cool. Hello everyone my name is Nick, but I'm joined by.

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And we're going to be talking about current quantum photography implementations.

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And with technology exists today, so, 1st, just a quick overview of what we're going to be talking about. We'll go.

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Cryptography currently, um, and how we can apply quantum mechanics to make it more secure.

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We'll have a few in a.

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In order to better relate our current photography implementations to these, these quantum implementations.

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And we'll talk about quantum key to physically how does it actually take place?

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And then 2, more of the theory behind it, you know, why does it work.

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Of 1, such quantum key distribution protocol.

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And then real quick, we'll talk about its existence in the commercial market today and you know where we're looking for the future.

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All right, so for the cryptography background.

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In case, not, everybody's familiar. It's just that cryptography is the.

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Uh, it's the math behind sending secure messages between 2 entities, or that'd be across the world or.

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10 kilometers away, so it's just communication in that aspect. Um, being.

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Available.

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Secure all those aspects in order to.

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Have your message, or he's sent a person that you needed to.

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Without anybody else snowing if you need that privacy.

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So, yeah, you can read for yourself these keys that, um.

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Encrypt and decrypt messages. These keys are mathematically secure.

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Um, with current technology right now it's an excellent.

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So, what we have in the current cryptography.

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Um, math that allows us to send secure messages, for example, is I know this is another presentation about this, so I don't want to go into detail over, take someone else's information, but I'd like to at least highlight that.

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With this scheme that relies on a key exchange.

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You'll we will find that this key exchange in particular.

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I'm focuses on the security of factoring up large prime number.

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Or factoring large numbers into their components so.

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That can be achieved in a finite time with quantum algorithms.

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So, when you can, when you can factor this, you can do this factor problem quickly.

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Uh, what's going on is that you can grab someone's private key. You can figure out that private key before.

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The receiver gets it or along with the receiver.

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So you can, uh, decrypt the messages that are being sent. So that's how the schemes being broken.

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Yeah, and other cryptography schemes rely on that. Yeah.

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For the next slide yeah, we have, um.

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So, in the general purpose, what's going on with.

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Uh, quantum security, so we know that quantum can break current algorithms.

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But we also now, there, it's a self solution that quantum can also fill the gap of security.

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So, what's going on is that.

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Quantum these quantum algorithms that are being developed are.

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Basically, just relying on the physics of supervision the, the whole.

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State of superposition. That cannot be right. It cannot be cloned or tampered with.

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Measured before someone else measures it again. So.

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Um, that's that's the secure part of sending.

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A cube in and just be in that singular component.

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So, with the large drawback, of course, with, uh, implementing a quantum cryptography system for the whole world to use, is that this would be a huge new infrastructure undertaking.

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So, there are proposed.

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There are proposed solutions with respect to different types of CubeSats of as, as we've seen. Um, Cubics can be represented as say, like, the polarization of a photon.

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Um, maybe the state of an Atom.

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Or an ion, so what we're focusing on, I have it bolded is that, um.

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Current cryptography implementations can be done through photons.

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So, and with the last respect to the last comment, if it is in the use of photons, Cuba.

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The latency speeds would be an important.

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Speed up, so, yeah. Um, I figured it would be best to just.

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Create the analogy with respect to the model, because security is in all layers. Right? So.

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Going from actually want to start in the bottom with the physical layer.

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And we know that conventional networks right now, I'm just rely on phone towers the 5 g towers that are being newly implemented in some fiber optic cables.

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If we were to implement a cubic system.

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Um, with respect to photons, we would want to use fiber optic cable.

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Maybe a higher quality, so you can maintain that.

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Polarization superposition or lasers.

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With respect to the, the analogy is a little fuzzy, but what I can say.

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Instead of, you know, a a radio signal.

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Um, say, being implemented in, for quantum, what could be done.

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Um, wirelessly is, um, doing a line of sight of lazy.

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Um, where he would have 1 device at, and a base station that is.

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Beaming direct, um, beams of light between each other to communicate.

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Another protocol that could be done is.

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With an entangled cubic protocol.

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Which is essentially being able to store a single photon and its state.

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And sending that along, and that says, um.

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That is capable as male as snail mail, right? Because you're just holding physical pieces of objects at a time to be sent over. And then it's.

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Your snail mail in Cuba I don't know if that's Super.

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Well, implemented, but it's possible, um, with respect to the network, um.

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There is no structure for that yet for.

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What has been researched with quantum cryptography?

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And with the last layer in application.

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We know conventional security deals with using.

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Um, which is the advance encryption suite.

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Or Elliptic curve, digital signature algorithm.

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So, because we can.

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Potentially break FISA algorithms. What? New algorithms for quantum.

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Um, and it's quantum math is implemented our deviate for.

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Which we're, we're going to focus on later, be 92.

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And which is made by.

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But it stands for the Einstein petoskey Rosen paradox.

222
00:23:58.169 --> 00:24:01.229
Um, for the last 2 layers, I just wanted to.

223
00:24:01.229 --> 00:24:06.808
Common about them for completeness. It's, um, that the transport layer is very.

224
00:24:06.808 --> 00:24:11.969
It's, it's obstructed from the file there, so you can just re, implement.

225
00:24:11.969 --> 00:24:15.808
Say into quantum, and for the presentation session layer.

226
00:24:15.808 --> 00:24:25.499
Again, they can be re, implemented on top of the quantum transport layer, but they're also not conventionally thought of as separate from the application and transport layer.

227
00:24:29.519 --> 00:24:33.509
Um, so for the physical layer, quantum key distribution.

228
00:24:33.509 --> 00:24:40.318
What I'm focusing what the research paper has given us research documentation has given us are 4 methods.

229
00:24:40.318 --> 00:24:43.469
Like, to focus on the 1st, 3, because.

230
00:24:43.469 --> 00:24:51.298
What this graph is telling us is that the, the attributes for continuous variables is not very viable besides it's.

231
00:24:51.298 --> 00:24:54.328
Um, speed potential, so I ignored that.

232
00:24:57.959 --> 00:25:04.439
All right, for a week laser pulses, this is has to do with, um, 2 aspects of.

233
00:25:04.439 --> 00:25:08.608
quantums, so the 1st aspect is what.

234
00:25:08.608 --> 00:25:11.848
Is being stored as the superposition upstate.

235
00:25:11.848 --> 00:25:15.509
Just 5 times, so we know we're using 5 times and.

236
00:25:15.509 --> 00:25:20.848
I just wanted to highlight that lasers aren't polarized like.

237
00:25:20.848 --> 00:25:24.088
It's just merely focussed light in a single direction. So.

238
00:25:24.088 --> 00:25:31.348
It can be polarized, so that's the supervision of state that's being sent over from 1.

239
00:25:31.348 --> 00:25:35.489
Uh, base station to another base station so.

240
00:25:35.489 --> 00:25:39.179
That's mostly straightforward I think, um, for the.

241
00:25:39.179 --> 00:25:44.699
Reliability, it's that he's the cubic representations. He's.

242
00:25:44.699 --> 00:25:52.618
Cubics are not are not unique. There are pulses of them so there's more than 1 being sent out a time.

243
00:25:52.618 --> 00:25:58.798
In order to increase that reliability and, uh, because you're sending more than 1 with the same state.

244
00:25:58.798 --> 00:26:04.439
You have a risk of someone intercepting a few of those and, uh.

245
00:26:04.439 --> 00:26:07.739
Capturing your message so there's that.

246
00:26:07.739 --> 00:26:11.128
Um.

247
00:26:11.128 --> 00:26:23.909
And the other aspect of the week, laser pulses is just how the technology is progress today. So what can be used already and is used today is a free space optical communication.

248
00:26:23.909 --> 00:26:27.598
Which are these laser.

249
00:26:27.598 --> 00:26:30.868
Transmitting and receiving devices that, uh.

250
00:26:30.868 --> 00:26:34.259
They have a a little spread as you can see. So.

251
00:26:34.259 --> 00:26:37.348
Is spread from 1 place to the other and.

252
00:26:37.348 --> 00:26:50.519
Uh, the direction is duplex, so it can come back, but the technology already exists and it has been recorded to go as far as 2.5 kilometers. Yeah. With a bandwidth of 10 gigabits per. 2nd.

253
00:26:50.519 --> 00:26:58.648
But of course, it's lasers that can be effected by strong weather conditions, such as fog sunlight.

254
00:26:58.648 --> 00:27:06.298
And, you know, physical instructions next line.

255
00:27:06.298 --> 00:27:13.858
And for the single photon source, this is only a flavor of week laser impulses. It's basically saying.

256
00:27:13.858 --> 00:27:24.298
If we can increase the reliability to 100% or very high percent of sending and receiving 1, single photon, 1, single Cupid at your time.

257
00:27:24.298 --> 00:27:27.929
We're increasing the security.

258
00:27:27.929 --> 00:27:33.118
You know, to a near perfect amount, right? Because there's only 1 cubic. And if that gets lost.

259
00:27:33.118 --> 00:27:36.689
That Cuba is no longer part of the security.

260
00:27:36.689 --> 00:27:40.378
Because it's been intercepted, so the way.

261
00:27:40.378 --> 00:27:45.989
This has been fully there's less physical technology available for this yet, but.

262
00:27:45.989 --> 00:27:50.189
What has been proposed is a nature nitrogen vacancy diamond.

263
00:27:50.189 --> 00:27:55.019
Which is basically a carbon structured to hold.

264
00:27:55.019 --> 00:27:59.699
A singular nitrogen atom and that nitrogen atom is excited.

265
00:27:59.699 --> 00:28:06.719
And it's a single photon at a time, something to that effect. And in order to store this futon.

266
00:28:06.719 --> 00:28:09.959
It's been proposed to use optical cavities.

267
00:28:09.959 --> 00:28:13.739
Which is the green picture right there? It's the ability to hold.

268
00:28:13.739 --> 00:28:18.028
Like, single photons out at a time single cubes at a time.

269
00:28:19.588 --> 00:28:23.818
For the next slide, all we have left are entangled pairs.

270
00:28:23.818 --> 00:28:26.999
And this has also been viable technology.

271
00:28:26.999 --> 00:28:31.348
Uh, created it's basically fiber optic cable.

272
00:28:31.348 --> 00:28:34.588
From a central source, the source it says.

273
00:28:34.588 --> 00:28:38.128
That central source is giving its.

274
00:28:38.128 --> 00:28:42.058
Is basically making an entangled pair of Cubics.

275
00:28:42.058 --> 00:28:46.828
Or sequence of events for Alice and Bob to use. So.

276
00:28:46.828 --> 00:28:52.709
Well, after you pair set 1, um, each 1 goes to.

277
00:28:52.709 --> 00:28:59.669
Alice and Bob, and then the next cube next to keep it there paired and 1 sent to Alice once and Bob.

278
00:28:59.669 --> 00:29:03.388
So, it's basically the entire scheme, um.

279
00:29:03.388 --> 00:29:12.209
With this fiber optics system, they've been able to send Q bits that are securely entangled.

280
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Out to tens of kilometers.

281
00:29:15.509 --> 00:29:20.219
So the only limit, of course, is the infrastructure of sending.

282
00:29:20.219 --> 00:29:26.759
Setting up fiber infrastructure to every single person, because it would be a central source. So.

283
00:29:26.759 --> 00:29:30.239
That's the main drawback of entangled parents.

284
00:29:30.239 --> 00:29:34.588
So that's all the physical key quantum distributions. There are.

285
00:29:37.888 --> 00:29:50.159
All right, so now we have looked at how to physically send or communicate via. But how is this actually helpful to implement some kind of cryptography system?

286
00:29:50.159 --> 00:29:57.808
So, in 1984, a protocol, the 8 4 protocol was.

287
00:29:58.973 --> 00:29:59.723
Was introduced,

288
00:30:00.054 --> 00:30:02.483
and this is a method of quantum key distribution,

289
00:30:02.483 --> 00:30:08.513
which basically uses Cubics to generate a secure sequence of bits that only the sender and receiver know,

290
00:30:09.144 --> 00:30:15.653
and this uses fundamentals of quantum physics and quantum mechanics in order to securely send and receive information.

291
00:30:15.894 --> 00:30:20.213
And even to detective, someone was dropping and trying to intercept that data.

292
00:30:20.548 --> 00:30:26.368
Um, so this this protocol takes place in 4 steps.

293
00:30:26.368 --> 00:30:37.318
Uh, the 1st step is Alice, the 1 who's going to initiate the communication? She will select 2 different orthogonal bases to encode the bits that are going to be sent.

294
00:30:37.318 --> 00:30:43.523
Um, and in the, the table on the right here, we can see the different bases that she has selected.

295
00:30:44.394 --> 00:30:53.423
So, for sake of simplicity, we call them the, the plus basis and the X pieces and you can see what 0T cube it at a 1 cube represent in each of those bases.

296
00:30:53.729 --> 00:31:02.519
So, Ellis then flips a coin and times in order to determine which bits she's going to send as your 1 in the classical sense.

297
00:31:02.814 --> 00:31:16.973
And then she'll flip the coin and other times, in order to determine the bases and wish to send the bids. So, the table at the bottom shows, the results of that, we have a random sequence of ones and zeroes and a random sequence of bases and that corresponds to.

298
00:31:17.818 --> 00:31:21.808
Her then sending Cubans above with certain.

299
00:31:21.808 --> 00:31:36.598
So, on the other end, Bob is going to receive all of these keywords and he is also going to just randomly flip a coin and times to determine the bases by which to measure the Cubans.

300
00:31:36.598 --> 00:31:45.328
So, he's going to measure using the X or the plus basis for each of those cubes and he'll end up with a sequence of classical bits out of that.

301
00:31:45.328 --> 00:31:56.818
Now, if he has guessed correctly for a certain bit, then his bit will match the 1 that Alice sent if he guesses wrong due to the nature of the bases his bit will match. Alice is 50% of the time.

302
00:32:00.953 --> 00:32:15.294
So the 3rd, step of this protocol is Bob and Alice connect via some kind of public communication channel could just be a phone call and Alice is going to tell Bob when he gets. Right?

303
00:32:15.354 --> 00:32:24.534
And when he yes. Wrong so note that the bits that were actually sent and received are not being communicated, but instead the bases by which the cubes were measured.

304
00:32:25.644 --> 00:32:35.723
So, if Bob guessed wrong, then they will just discard that corresponding bit. And so in this table, you can see Alice has bases that she used and Bob's bases.

305
00:32:36.023 --> 00:32:41.753
And anytime they agree, those are the bits that are going to end up in their shared secret key.

306
00:32:42.058 --> 00:32:53.729
The sequence that they end up with is identical, unless someone was listening in on the quantum channel and that brings us to the 4th step and the last step of the critical.

307
00:32:53.729 --> 00:33:07.558
So, if someone measures, the Cuban during its transfer, it will change the quantum state. Right? If someone measures the cubic, while it's being sent, it'll collapse to 1 of the basis states that was used to measure it.

308
00:33:07.558 --> 00:33:16.499
Um, and those changing the quantum state that Alice originally sent to keep it in. And so Allison, Bob can use this to check for East dropping. So.

309
00:33:16.499 --> 00:33:23.159
I was involved, we're going to compare they're going to randomly select half of the remaining bits and they're going to publicly compare them.

310
00:33:23.159 --> 00:33:36.898
If the bits disagree, then they will start over completely because now they know that a significant portion of the bits that they sent, even though they were sent and received using the same basis.

311
00:33:36.898 --> 00:33:47.878
They disagree so there was some tampering while they are being transferred. So they'll, they'll completely start over. However, if their bits are mostly similar.

312
00:33:47.878 --> 00:33:55.528
You know, and maybe the error can be attributed to imperfect communication or the States being.

313
00:33:55.854 --> 00:34:10.043
Being affected just well being sent, then they will just discard the shared bits and the remaining bits are the security key. Now, Allison, Bob have a sequence of classical ones and zeros that only they know and that they can be.

314
00:34:10.224 --> 00:34:13.164
Absolutely sure. No, 1 else has tampered with.

315
00:34:13.469 --> 00:34:25.619
So this doesn't mean though that if the original number of bits that Alison was was N, the resulting key has link and over 4 on average in step 3, they.

316
00:34:25.619 --> 00:34:29.579
On average, we'll toss out half of the bits and then in this step, they'll toss out another half.

317
00:34:29.579 --> 00:34:39.059
But that's okay, because Alice can just send an arbitrary number of Cubics. So, do you want a 64 bit key? You said, 264 or? Sorry? 256 Cubans.

318
00:34:40.733 --> 00:34:53.873
And then, just as a quick aside, there are other quantum key distribution protocols. There's the B92 protocol, which was introduced in 1992, very similar to this critical, but instead uses 1 non orthogonal basis to encode the.

319
00:34:56.128 --> 00:35:08.398
And then there's the protocol that we mentioned earlier, which is again very similar to this protocol, but instead of using some physical channel uses a form of quantum entanglement to communicate.

320
00:35:13.463 --> 00:35:24.893
So, where are we today right? This, all kind of sounds like, you know, some hand wavy SciFi but there are many companies that already develop these quantum distribution solutions.

321
00:35:25.978 --> 00:35:35.909
You can, you can see the companies here ranging from Boston, mass to Geneva, in Switzerland, Cadbury, Australia or even Paris France.

322
00:35:37.884 --> 00:35:46.373
And there are some important milestones that have been achieved in 2004 in Austria, the 1st, bank transfer that was secured using a quantum distribution system, took place.

323
00:35:46.673 --> 00:35:59.003
And in 2007, in Geneva, Switzerland, this company ID, quanti, implemented a quantum encryption system to securely transmit ballot results to the capital in their national election.

324
00:35:59.003 --> 00:36:01.853
And that system is actually still being used today.

325
00:36:03.509 --> 00:36:06.989
Um, and 2013.

326
00:36:06.989 --> 00:36:18.869
The patellar moral Institute installed a Q, Katy system between their main campus in Ohio, and their manufacturing facility in Dublin. So these things have been proven to work and they're even being implemented today.

327
00:36:18.869 --> 00:36:25.349
So looking to the future a little bit.

328
00:36:25.349 --> 00:36:28.559
There are a few problems that have been introduced with Q, Katie.

329
00:36:28.559 --> 00:36:32.909
Um, the 1st is a key management problem so, um.

330
00:36:32.909 --> 00:36:39.358
You know, we have to store and we have to generate a bunch of pairwise keys for every.

331
00:36:39.358 --> 00:36:44.608
Every pair of users on our network and so story and that becomes very difficult.

332
00:36:44.608 --> 00:36:57.119
And then as a result of the no cloning theory, Katie can only provide 1 to 1 connections. So if and is the number of nodes, then the number of links is going to scale up exponentially with regards to end.

333
00:36:57.119 --> 00:37:02.039
And then there are a couple different versions here that we, that we quickly mentioned.

334
00:37:02.039 --> 00:37:06.599
There's an idea of 3 stage quantum cryptography.

335
00:37:06.599 --> 00:37:21.114
Which is an extension of the double lock cryptography where Allison, Bob, both have some kind of random polarization rotation that they apply to a series of Cubics as their lock. So Alice would apply that send it to Bob.

336
00:37:21.414 --> 00:37:30.773
Bob would apply his and send it back to Alice. She would verify there's been no tampering and then would undo her polarization, send it back to Bob and he would undo his. And now he has the.

337
00:37:31.168 --> 00:37:44.128
Um, on unencrypted data, and then there's also an idea of quantum digital signatures. So an individual can sign some data in such a way that all recipients can verify that it came from that person.

338
00:37:44.128 --> 00:37:51.148
And instead of using a classical sequence of ones, and zeroes, you can use a series, a set of quantum states as your public key.

339
00:37:52.768 --> 00:37:58.048
So, yeah, that's that's what we got.

340
00:37:58.048 --> 00:38:03.958
Well, thank you very much. I learned a lot. I'm for 1 quick question and then.

341
00:38:08.548 --> 00:38:20.010
Okay, so next is David and David. If you still, I can show your video.

342
00:38:22.860 --> 00:38:27.210
Or, can you show it just a 2nd.

343
00:38:29.579 --> 00:38:33.420
No, I have to get that would be preferable.

344
00:38:33.420 --> 00:38:36.869
Okay, I just have to get a cable back in a minute.

345
00:38:40.860 --> 00:38:45.420
Silence.

346
00:38:55.860 --> 00:38:59.489
It's the 2nd, here.

347
00:39:53.699 --> 00:40:00.389
You're on TV.

348
00:40:31.889 --> 00:40:33.000
Okay.

349
00:40:48.750 --> 00:40:55.679
Right. It doesn't sound like there's any audio coming from the video, right? Yeah, that's what I.

350
00:40:55.679 --> 00:40:59.010
Trying to figure out cause I.

351
00:41:01.769 --> 00:41:06.119
Right.

352
00:41:06.119 --> 00:41:12.989
Can you hear this.

353
00:41:12.989 --> 00:41:18.150
No, I don't hear it.

354
00:41:18.150 --> 00:41:21.599
Yeah, we can hear you, but we cannot hear any kind of video.

355
00:42:08.460 --> 00:42:11.639
More complex.

356
00:42:11.639 --> 00:42:14.969
Credit card.

357
00:42:14.969 --> 00:42:21.750
For.

358
00:42:22.980 --> 00:42:28.260
Can you hear that?

359
00:42:30.750 --> 00:42:37.409
Very, yeah, it's like, we can hear it through a microphone through a speaker. It's not actually hearing it.

360
00:42:37.409 --> 00:42:54.510
Silence.

361
00:42:54.510 --> 00:42:58.650
Silence.

362
00:43:00.840 --> 00:43:13.050
Might have to.

363
00:43:24.480 --> 00:43:38.130
By.

364
00:44:31.170 --> 00:44:36.210
Yes, yeah.

365
00:44:58.769 --> 00:45:08.639
Trick is getting the ball. I am actually patching it to the Mike because the video is not feeding into.

366
00:45:08.639 --> 00:45:18.480
Webex videos feeding in the audio is not feeding into Webex. So basically.

367
00:45:20.460 --> 00:45:23.639
If this is, this is.

368
00:45:24.780 --> 00:45:33.300
Article.

369
00:45:33.300 --> 00:45:40.980
So, what is.

370
00:45:40.980 --> 00:45:44.730
This is not working.

371
00:46:06.780 --> 00:46:12.690
To used widely across the Internet as.

372
00:46:12.690 --> 00:46:20.250
More complex.

373
00:46:20.250 --> 00:46:24.480
For me.

374
00:46:27.480 --> 00:46:36.659
Private.

375
00:46:36.659 --> 00:46:41.760
Or it is even used for more based on things such as age.

376
00:46:41.760 --> 00:46:45.210
It was passing in by Ronald Dell.

377
00:46:45.210 --> 00:46:50.550
Eddie Shamir and honored and Edelman and is named after them.

378
00:46:50.550 --> 00:46:54.150
With each letter, being an initial.

379
00:46:54.150 --> 00:47:01.320
Each of their last names so how does it work? Well, on a basic level, it works by using public keys.

380
00:47:01.320 --> 00:47:10.769
Everyone has public and private keys. The public key is used to encrypt data that will be sent to them. And the private key is to decrypt.

381
00:47:10.769 --> 00:47:20.489
Their specific public, so the process is done by the receiver, giving the sending party in their public key center. Then.

382
00:47:20.489 --> 00:47:24.360
Uses that came to encrypted their data and transfer it to a receiver.

383
00:47:24.360 --> 00:47:27.360
Then you receiver then decrypt the data.

384
00:47:27.360 --> 00:47:31.230
Using their private key so a.

385
00:47:31.230 --> 00:47:34.980
Initial example of this is joining this picture where.

386
00:47:34.980 --> 00:47:44.909
Bob has a box and a lock that is unlocked and he sends the empty box in the unopened lock or the open block to Alice.

387
00:47:44.909 --> 00:47:54.059
And then Allison uses the open lock, and then puts in the valuable information in this case, the diamond into the box, and then locks it and using.

388
00:47:54.059 --> 00:48:00.809
Bob slock and then as soon as the lockbox back to Bob presents, Bob had.

389
00:48:00.809 --> 00:48:03.900
Silence.

390
00:48:03.900 --> 00:48:07.949
Silence.

391
00:48:10.559 --> 00:48:18.179
1 minute.

392
00:48:18.179 --> 00:48:21.960
Silence.

393
00:48:24.030 --> 00:48:33.989
Silence.

394
00:48:44.400 --> 00:48:49.349
Silence.

395
00:48:49.349 --> 00:48:54.090
Silence.

396
00:48:56.340 --> 00:49:02.369
Silence.

397
00:49:02.369 --> 00:49:11.940
Silence.

398
00:49:11.940 --> 00:49:20.340
Silence.

399
00:49:34.260 --> 00:49:37.739
Silence.

400
00:49:41.280 --> 00:49:58.739
Silence.

401
00:50:02.519 --> 00:50:07.829
Yeah, I kick it. No, 1 was saying the video is that correct?

402
00:50:09.150 --> 00:50:14.159
Yeah, yeah, correct.

403
00:50:16.650 --> 00:50:23.159
Silence.

404
00:50:23.159 --> 00:50:28.380
Silence.

405
00:50:28.380 --> 00:50:33.989
Silence.

406
00:50:39.179 --> 00:50:43.860
Silence.

407
00:50:45.389 --> 00:50:51.869
I was going to stop and restart the application. It's all. It's all I can think to do.

408
00:50:54.150 --> 00:51:52.679
Silence.

409
00:52:03.780 --> 00:52:14.219
Bronto Dell Shamir.

410
00:52:14.219 --> 00:52:18.300
And Dylan, or defend Edelman and named after them.

411
00:52:18.300 --> 00:52:24.360
Also, today, I'm going to be talking about.

412
00:52:24.360 --> 00:52:31.619
So, what is our is a public P encryption protocol we're sending data between 2 parties.

413
00:52:31.619 --> 00:52:35.010
It is used widely across the Internet in.

414
00:52:35.010 --> 00:52:39.690
Various use cases, such as more complex things such as.

415
00:52:39.690 --> 00:52:42.840
Passwords and credit card.

416
00:52:42.840 --> 00:52:49.679
Information private, or it is even used for more based on things such as age.

417
00:52:49.679 --> 00:52:53.760
It was patching in by frontal Dell, brightest.

418
00:52:53.760 --> 00:52:56.880
Eddie Shamir and Leonard Edelman.

419
00:52:56.880 --> 00:53:01.260
And it is named after them with each letter being.

420
00:53:01.260 --> 00:53:04.320
Initial each of their last names.

421
00:53:05.340 --> 00:53:09.840
So, how does it work? Well, and a basic level it works by using public keys.

422
00:53:09.840 --> 00:53:15.630
Everyone has public and private keys, and the public key is used to encrypt the data.

423
00:53:15.630 --> 00:53:19.289
That will be sent to them and if the private key is to decrypt.

424
00:53:19.289 --> 00:53:23.130
They're specific public, so they.

425
00:53:23.130 --> 00:53:29.039
Process is done by the receiver, giving the sending party of their public key. They send her then.

426
00:53:29.039 --> 00:53:32.969
Uses that came to encrypted their data and transfer it to a receiver.

427
00:53:32.969 --> 00:53:38.130
Then the receiver then decrypts the data using their private key.

428
00:53:38.130 --> 00:53:43.559
So, a visual example of this is joining this picture where.

429
00:53:43.559 --> 00:53:47.639
Bob has a box and a lock that is unlocked.

430
00:53:47.639 --> 00:53:52.110
And he sends the empty box and the unopened lock or the open lock.

431
00:53:52.110 --> 00:53:56.429
To Alice and Alice, and uses the open lock.

432
00:53:56.429 --> 00:54:02.610
And then puts in the valuable information in this case, the diamond into the box, and then locks it using.

433
00:54:02.610 --> 00:54:11.219
Bob's lock and then the lock box back to Bob, and since Bob has the key to that lock.

434
00:54:11.219 --> 00:54:17.250
He's the only 1 who can unlock it and us is the only 1 able to access the diamond that is inside.

435
00:54:19.079 --> 00:54:25.050
So, how does specifically work on a mathematical basis? Well, for making a public key.

436
00:54:25.050 --> 00:54:31.260
The computer picks 2, random, large prime numbers. Let's call them.

437
00:54:31.260 --> 00:54:34.650
Then they are multiplied together to get an.

438
00:54:34.650 --> 00:54:41.070
And then a number he is picked that is relatively prime 2 P minus 1 times. Q minus 1.

439
00:54:41.070 --> 00:54:44.340
Relatively meaning that meaning that they share.

440
00:54:44.340 --> 00:54:51.539
Only a common factor of 1 a public key is made up of Andy.

441
00:54:51.539 --> 00:54:57.329
Then a private key is made, which is done by getting the modulator inverse of.

442
00:54:58.710 --> 00:55:01.889
In mod P minus 1 times Q minus 1.

443
00:55:01.889 --> 00:55:06.539
Which would be, it can be solved using the equation scene on screen.

444
00:55:06.539 --> 00:55:10.829
And that can be done to use any utility and division algorithm.

445
00:55:10.829 --> 00:55:16.289
And the private key would be the sender, then encrypts their data.

446
00:55:16.289 --> 00:55:20.250
By having their data, as let's say number am.

447
00:55:20.250 --> 00:55:24.510
And then using the receivers public key.

448
00:55:24.510 --> 00:55:27.539
They do amateur.

449
00:55:27.539 --> 00:55:30.960
Mart, and get to see which is the data.

450
00:55:30.960 --> 00:55:36.150
Send a receive send sender of the data, receive a receives the data.

451
00:55:36.150 --> 00:55:40.199
And the receiver decrypts the data using their private key.

452
00:55:40.199 --> 00:55:43.590
By doing see the.

453
00:55:43.590 --> 00:55:46.679
Model and and getting back to the message.

454
00:55:49.079 --> 00:55:53.099
So, why does it work? Well, it works because.

455
00:55:53.099 --> 00:55:56.219
It is using large prime numbers and.

456
00:55:56.219 --> 00:56:01.199
For doing that encryption is very easy, because selecting and multiplying large number is.

457
00:56:01.199 --> 00:56:05.909
Together is a very quick and easy operation for a computer to solve.

458
00:56:05.909 --> 00:56:09.150
However, description is a very hard.

459
00:56:09.150 --> 00:56:12.269
Thing to solve if you do not have the.

460
00:56:12.269 --> 00:56:16.710
Fact, very large numbers is computationally very difficult and very expensive.

461
00:56:16.710 --> 00:56:22.289
Especially for numbers that are made up of 2 crimes.

462
00:56:22.289 --> 00:56:25.320
Because there are only those 2.

463
00:56:25.320 --> 00:56:30.389
Those 2 factors, and it takes a long time for leaders to solve this thing.

464
00:56:31.619 --> 00:56:37.920
And especially today we're using 2048 bit numbers.

465
00:56:37.920 --> 00:56:43.320
It is considered impossible to solve because it would just take so long.

466
00:56:43.320 --> 00:56:46.769
For a traditional computer to solve that. It is not.

467
00:56:46.769 --> 00:56:51.929
Equivalent to being done within a lifetime.

468
00:56:54.059 --> 00:56:59.820
But what about quantum computers? Well, in 1994 and Peter shore discovered an algorithm.

469
00:56:59.820 --> 00:57:04.860
I would allow quantum computers to factor large number of years at a substantially better rate.

470
00:57:04.860 --> 00:57:11.489
Classical computers this was done by using a specific factoring.

471
00:57:11.489 --> 00:57:16.170
Method and was optimized in the.

472
00:57:16.170 --> 00:57:23.849
Mathematical space in 2014 physicists used before, but quantum computer to factor.

473
00:57:23.849 --> 00:57:27.090
56153, which.

474
00:57:27.090 --> 00:57:30.329
Well, it doesn't seem like a.

475
00:57:30.329 --> 00:57:33.780
Large accomplishment. It is a very large number to.

476
00:57:34.860 --> 00:57:39.000
Factor using Cubans.

477
00:57:39.000 --> 00:57:44.519
In 2015 researchers estimated that a 1B cubic computer.

478
00:57:44.519 --> 00:57:48.630
What we needed in order to factor 8 2048.

479
00:57:48.630 --> 00:57:53.820
The number, which is good because.

480
00:57:53.820 --> 00:57:58.860
Uses 2048 bit encryption. Most of the time.

481
00:57:58.860 --> 00:58:01.949
And, however, in 2019.

482
00:58:01.949 --> 00:58:06.449
Disney and Martin come up with a method.

483
00:58:06.449 --> 00:58:10.590
Or using a 20M to the computer 2 factor.

484
00:58:10.590 --> 00:58:14.909
24 to 8, big numbers within the hours they both optimized to the.

485
00:58:14.909 --> 00:58:18.840
Hardware side of the algorithm.

486
00:58:18.840 --> 00:58:23.039
As well as the mathematical side, so.

487
00:58:23.039 --> 00:58:26.550
Is our safe safe mostly yes. For now.

488
00:58:26.550 --> 00:58:29.610
Because most systems use, at least.

489
00:58:29.610 --> 00:58:33.599
2048 bit numbers, which are, as I said before.

490
00:58:33.599 --> 00:58:36.690
Essentially, the impossible to solve with traditional computers.

491
00:58:36.690 --> 00:58:40.679
And even as traditional computers increase in speed.

492
00:58:40.679 --> 00:58:46.230
Most data will become significant in the amount of time it would take to the data.

493
00:58:46.230 --> 00:58:50.039
And quantum computers. Wow.

494
00:58:50.039 --> 00:58:53.820
Are able to solve that problem at some point it.

495
00:58:53.820 --> 00:58:57.179
There's still ways away from being able to crack.

496
00:58:57.179 --> 00:59:01.949
At the level that would be dangerous to people and.

497
00:59:01.949 --> 00:59:05.340
If it's not safe for the future security experts.

498
00:59:05.340 --> 00:59:10.110
Have already created cryptography methods that cannot be solved by quantum computers.

499
00:59:10.110 --> 00:59:14.639
And those will be implemented, should on the fingers, be a correct for our site.

500
00:59:14.639 --> 00:59:19.380
Thank you for listening to my presentation.

501
00:59:20.699 --> 00:59:23.820
Okay.

502
00:59:23.820 --> 00:59:30.300
Thank you gave time for a quick.

503
00:59:30.300 --> 00:59:34.500
Question.

504
00:59:34.500 --> 00:59:40.949
I'm just having to switch switch the on where.

505
00:59:40.949 --> 00:59:45.719
Silence.

506
00:59:45.719 --> 00:59:52.800
Okay.

507
00:59:58.289 --> 01:00:06.539
Switching the audio back to a normal situation and.

508
01:00:15.599 --> 01:00:24.869
Good. Okay, well, 1, question for you is there a cryptography and printed material that might still you want to keep secret after many years?

509
01:00:26.250 --> 01:00:30.210
Think about that uh, yeah.

510
01:00:30.210 --> 01:00:38.730
Yeah, especially yeah, it's not super risky for normal people, but for, like, confidential government data.

511
01:00:38.730 --> 01:00:44.010
And perhaps high level company data after, like, 2025 years.

512
01:00:44.010 --> 01:00:48.659
Uh, data can still be important 1 of the corrected at that time.

513
01:00:49.800 --> 01:00:59.099
Yeah, we're seeing stuff in the news, I guess, or post the politicians made 20, 30 years ago perhaps might come back and.

514
01:00:59.099 --> 01:01:03.570
There's still stuff from World War 2 I think, which has, which is still.

515
01:01:03.570 --> 01:01:11.130
Secret, and I'm guessing it might be prominent people are secretly on the other side or something. So it may be some stuff.

516
01:01:11.130 --> 01:01:17.010
Um, okay, so let's see. Thanks, Dave.

517
01:01:17.010 --> 01:01:22.769
John Rawlinson you tell us about coherence.

518
01:01:22.769 --> 01:01:27.750
Yeah, can you hear me? I can hear you. Yes, I can see you.

519
01:01:27.750 --> 01:01:30.989
Okay, cool. Let me just share my screen.

520
01:01:30.989 --> 01:01:34.920
And I can see your screen. Okay.

521
01:01:45.204 --> 01:01:58.704
Okay, so I'm going to be talking about a D and how do you coherence is essentially how we relate the quantum world to the classical world or, in other words, the.

522
01:01:59.309 --> 01:02:03.809
Classical reality, it can be reconciled with the quantum world.

523
01:02:03.809 --> 01:02:13.440
So, it might give a brief introduction to what is DCO parents and talk about the motivation for why coherent is essentially necessary.

524
01:02:13.440 --> 01:02:20.429
And some of the implications of coherence in quantum computing, and then give a short example of coherence in quantum.

525
01:02:21.804 --> 01:02:22.135
So,

526
01:02:22.164 --> 01:02:22.974
throughout this paper,

527
01:02:23.364 --> 01:02:24.474
or throughout this presentation,

528
01:02:24.474 --> 01:02:27.414
I'll be referencing this review paper by well,

529
01:02:27.414 --> 01:02:28.583
known theoretical physicist,

530
01:02:28.855 --> 01:02:29.485
which exert,

531
01:02:30.054 --> 01:02:35.905
and essentially tells us that DCO hands is caused by the interaction of the environment,

532
01:02:36.414 --> 01:02:38.125
which in effect monitors certain,

533
01:02:38.125 --> 01:02:39.744
observe a system,

534
01:02:39.804 --> 01:02:40.375
destroying,

535
01:02:40.405 --> 01:02:41.005
inherent,

536
01:02:41.485 --> 01:02:43.764
destroying coherence between the pointer States.

537
01:02:44.070 --> 01:02:49.710
Corresponding to their values, this leads to environment induced Super selection or selection.

538
01:02:49.710 --> 01:02:55.889
A quantum process associated with a selective loss of information. So this is kind of a very, um.

539
01:02:55.889 --> 01:03:07.050
Sort of detailed explanation of what enhances, but essentially the main points are that results from the interaction of the quantum system with its environment.

540
01:03:07.050 --> 01:03:13.679
And in this interpretation, we have to view the environment as an observer of a quantum system.

541
01:03:13.679 --> 01:03:19.409
And the results of this observation by the environment is a selective loss of information.

542
01:03:20.610 --> 01:03:29.940
So, the origins of DCO heads basically relate back to the origins of quantum mechanics and in the early 19th and 19 twenties.

543
01:03:29.940 --> 01:03:34.710
Um, a lot of people really had a big problem with quantum mechanics in that.

544
01:03:34.710 --> 01:03:47.400
A quantum mechanics seem to fly in the face of classical mechanics and sort of objective reality as we know it. So, this led to an issue of what people term an existential interpretation of quantum mechanics.

545
01:03:47.400 --> 01:03:53.909
In that, how can we have sort of a deterministic objective? Reality of quantum mechanics tells us.

546
01:03:53.909 --> 01:03:57.480
That sort of all states exist with equal profitability.

547
01:03:57.480 --> 01:04:03.059
And, um, and there should be no sort of determinism in our universe.

548
01:04:03.059 --> 01:04:08.039
So, run interpretation of this was the Copenhagen interpretation.

549
01:04:08.039 --> 01:04:17.849
Uh, the main proponent of whom was a board, and boy essentially said, um, in order to reconcile the differences between quantum and classical systems.

550
01:04:17.849 --> 01:04:30.960
We, we will just drop box around quantum systems and add small scales, quantum systems exist. And and once we go outside of that box into, sort of the world that we live in, this is where the classical world exists.

551
01:04:30.960 --> 01:04:43.260
And this is sort of related, to course, correspondence principle, which is essentially a mathematical proof that you can show that, as the scale of a quantum system increases to sort of macroscopic scales. It.

552
01:04:43.260 --> 01:04:44.724
It becomes a classical system,

553
01:04:45.835 --> 01:04:52.255
the sort of competing interpretation for this is the many worlds interpretation created by Everett 30 years later in 1957,

554
01:04:52.255 --> 01:05:02.094
and ever essentially said that we can't view quantum systems as as closed or isolated quantum system necessarily has to interact with with its environment.

555
01:05:03.090 --> 01:05:09.360
And because of this, we essentially have to consider the entire universe as 1.

556
01:05:09.360 --> 01:05:17.400
Gigantic quantum system 1, gigantic quantum state vector and reality is sort of the evolution of this quantum state vector.

557
01:05:17.400 --> 01:05:21.360
Through it's, um, through its probable States.

558
01:05:22.679 --> 01:05:32.369
So, the issue with these interpretations is that, while they sort of try to reconcile the differences between quantum and classical mechanics.

559
01:05:32.369 --> 01:05:36.690
They don't really explain how the 2 are related.

560
01:05:36.690 --> 01:05:44.670
And essentially, in the years following that, mostly in the 19 seventies up until 1980.

561
01:05:44.670 --> 01:05:48.809
There was sort of developed this idea that, um.

562
01:05:48.809 --> 01:05:54.659
Parents is is how quantum mechanics relates to class mechanics.

563
01:05:54.659 --> 01:06:00.179
And essentially what it says is that in quantum physics, we can think of.

564
01:06:00.179 --> 01:06:03.840
Reality is is is measurement.

565
01:06:03.840 --> 01:06:10.050
Um, so, in order to observe something, or the observation of something, uh, implies the existence of something.

566
01:06:10.050 --> 01:06:23.699
And measurement is this really just information transfer between a system and its environment, or really information transfer between 1 part of a system and another part of that system.

567
01:06:23.699 --> 01:06:32.550
So this environment acting as an observer, essentially imposes a set of Super selection rules.

568
01:06:32.550 --> 01:06:44.460
So essentially what these super selection rules do is, they say that we really reduce the dimensionality of deliberate space, which is theoretically infinite in size and its number of dimensions.

569
01:06:44.460 --> 01:06:48.480
Uh, down to a a reduced density matrix.

570
01:06:48.480 --> 01:06:52.380
Of essentially a set of.

571
01:06:52.380 --> 01:06:57.719
Um, most probable States, which exist determined by the.

572
01:06:57.719 --> 01:07:05.639
The environment, so this is essentially how we get sort of a classical determinism from a.

573
01:07:05.639 --> 01:07:08.940
grantable quantum probabilistic system.

574
01:07:08.940 --> 01:07:12.989
Is that the environment imposes sort of.

575
01:07:12.989 --> 01:07:17.070
A very small set of states, which can exist.

576
01:07:17.070 --> 01:07:23.429
And so this is really the fundamental idea of inherent is that.

577
01:07:23.429 --> 01:07:27.210
Nature or the environment allows only.

578
01:07:27.210 --> 01:07:33.119
Certain States to exist and, uh, and in quantum computing is often.

579
01:07:33.119 --> 01:07:38.579
And when people talk about it, they often lump it together with sort of energy, relaxation or classical noise.

580
01:07:38.579 --> 01:07:53.394
But they are fundamentally 2 separate things, energy, relaxation and classical noise are really the outside environment sort of impinging on a quantum system whereas coherence can really be thought of as.

581
01:07:53.730 --> 01:07:58.679
A quantum system transferring information to to the surrounding environment.

582
01:08:00.150 --> 01:08:06.750
So, the implications of this in quantum computing are essentially that for, for any given Cupid modality uh, we have.

583
01:08:06.750 --> 01:08:11.309
A, this D, coherence time, which is really the, the amount of time in which.

584
01:08:11.309 --> 01:08:23.189
We can do operations on a Cuban essentially we prepare a cube it by forcing it into a pure state, but the surrounding environment does not want this pure state to exist. So, it eventually decays into a.

585
01:08:23.189 --> 01:08:26.760
Essentially state, so.

586
01:08:26.760 --> 01:08:30.569
And this leads to an issue with all cubic modalities in that.

587
01:08:30.569 --> 01:08:36.630
We want Cubics, which interact weekly with their environment and us have long coherence times.

588
01:08:36.630 --> 01:08:47.520
But the other side of this is that if a cube interacts weekly with its environment, it means that it's also difficult for us to perform data operations. And to do.

589
01:08:47.520 --> 01:08:50.850
Uh, essentially, they take longer to do so, um.

590
01:08:50.850 --> 01:08:58.319
Here we just have a table which gives some examples of of different coherence times and different, uh, cubic modalities.

591
01:08:58.319 --> 01:09:04.260
Most notably we can look at the micro cavity, which is essentially what cubes are based on.

592
01:09:04.260 --> 01:09:10.409
And the sort of crude, theoretical DCO, Harris, time of microwave cavity is around 3rd.

593
01:09:10.409 --> 01:09:14.579
And in this time we could do about 10000 operations on a cube.

594
01:09:14.579 --> 01:09:21.149
We know from experience with Cubans that the amount of operations you can do is actually much much less than that.

595
01:09:22.319 --> 01:09:28.020
So, just to give an example of coherence in in quantum computing, um.

596
01:09:28.020 --> 01:09:32.609
Most problems forms is depolarization. Uh, essentially the.

597
01:09:32.609 --> 01:09:38.189
The state of the cube it after being prepared is is transferring from a pure state to a mixed state.

598
01:09:38.189 --> 01:09:45.420
And we can basically think about a mixed state as a state, which no longer retains the quantum properties of the system.

599
01:09:45.420 --> 01:09:50.729
So, in a mix state, we don't have things like superposition or interference.

600
01:09:50.729 --> 01:09:55.560
Which are really the basis of quantum computing, so we can't we can't do any computation with it. Mixtape.

601
01:09:55.560 --> 01:10:06.119
So, as as a quantum circuit, we can sort of see this as a control swap gate between the original prepared cube and the mix state.

602
01:10:06.119 --> 01:10:12.210
Uh, with some transition profitability PE, and looking at it in in the lens of the blocks here.

603
01:10:13.829 --> 01:10:23.279
The, the depolarization essentially amounts to a loss of information in our system. The size of our block sphere reduces.

604
01:10:23.279 --> 01:10:27.149
Indicating that the magnitude of our pure state is less than 1.

605
01:10:27.149 --> 01:10:36.479
So, looking just within the closed system of the cube, this is a non unitary and irreversible process. Um.

606
01:10:36.479 --> 01:10:46.439
That that, as I said, before, basically results in the loss of information, of course, if we view it in larger context of the environment as 1, large quantum system.

607
01:10:46.439 --> 01:10:54.210
It's really not a non unitary or irreversible process, but really, it's the, it's the transfer of information to the surrounding environment.

608
01:10:54.210 --> 01:10:57.989
And if we had sufficient knowledge of the surrounding environment, we could.

609
01:10:57.989 --> 01:11:04.289
In theory, reverse that process. So.

610
01:11:04.289 --> 01:11:17.880
In summary, uh, D, coherence causes on selection, which is the selection of classical States, or the selection of preferred States by the environment, which leads to sort of classical reality as we know it.

611
01:11:17.880 --> 01:11:26.279
And it's really, in this way, coherence explains the coexistence of classical and quantum mechanics. How can we.

612
01:11:26.279 --> 01:11:32.220
Reconciled determinism of classical mechanics versus the private ballistic nature of quantum mechanics.

613
01:11:32.220 --> 01:11:38.279
But in quantum computing, this really translate to the inevitable loss of the information stored within our cube.

614
01:11:38.279 --> 01:11:44.220
And this DCO Harris time itself depends on how strongly a cube it interacts with its environment.

615
01:11:44.220 --> 01:11:49.409
So, this DCO parent's is really the main motivator for the need for quantum error correction.

616
01:11:51.569 --> 01:11:55.109
And then these are the 2 sources that I referenced throughout my presentation.

617
01:11:55.109 --> 01:12:01.529
So, I can take any questions at this time. Thank you. Time per question.

618
01:12:03.479 --> 01:12:06.989
I'll ask 1. no. Oh, sorry. Go ahead.

619
01:12:06.989 --> 01:12:13.050
Okay, yeah, so the question in the chat was, do you know why IBM shows the micro cavity other other Cuba types?

620
01:12:13.050 --> 01:12:16.109
That theoretically allowed for more operations.

621
01:12:16.109 --> 01:12:20.970
I the way that I understand it is basically IBM is looking for a highly scalable process.

622
01:12:20.970 --> 01:12:25.920
So, by leveraging microwave cavities, they're, they're building a, a.

623
01:12:25.920 --> 01:12:31.979
Cuba, which they can build off of semiconductor processes and in theory scale very rapidly.

624
01:12:31.979 --> 01:12:39.000
Although there clearly been a lot of barriers to that scaling.

625
01:12:39.000 --> 01:12:43.439
Oh, thank you. Oh, okay.

626
01:12:43.439 --> 01:12:49.260
Honor, em, ago and said our Suri will teach us about bell theorum.

627
01:12:50.939 --> 01:12:59.520
How can you hear me? Yes, I can hear you. All right. It's my 3rd too. Yes, I can also hear you.

628
01:12:59.520 --> 01:13:03.329
I can share it.

629
01:13:03.329 --> 01:13:09.930
I can see your screen.

630
01:13:14.789 --> 01:13:27.085
Whereas all right, so we're going to steam a bell serum, so we're just go through 4 meetings. Go over what bell serum is professor Franklin mentioned it earlier in the semester.

631
01:13:27.085 --> 01:13:34.314
We're talking about just proving hidden variables. Excuse us? Something called bell's inequality, which we will also cover.

632
01:13:34.619 --> 01:13:40.079
We're gonna walk through example, experiment that it can be done, uh, perform 2.

633
01:13:40.079 --> 01:13:45.930
Uh, examples and then show some loopholes that exists and how they've been dealt with.

634
01:13:45.930 --> 01:13:49.560
So, what is Sarah.

635
01:13:49.560 --> 01:14:00.715
So concerns the existence of hidden variables that kind of how a particle or entangled particles will resolve when they're measured.

636
01:14:01.314 --> 01:14:11.335
So, the example provided in our sources, a neutral plan, which decomposed into 2 photons they have the same way function. Therefore, opposite spin.

637
01:14:12.204 --> 01:14:22.494
If you let these photons travel, let years apart and then measure 1, it's collapsing the way function by definition. So, you know, the span of this 1 and, you know, that's been with the other ones and say, have to be.

638
01:14:23.935 --> 01:14:31.373
Opposite, um, then, that means this 1st measurement must be poisoning the 2nd measurement even across light years.

639
01:14:31.914 --> 01:14:42.234
So, if there is no hidden variable, does that mean there's a violation of special relativity because you've measured 1 and the other 1 is a waste and result instantly.

640
01:14:43.050 --> 01:14:54.779
So, to avoid violating special relativity, you can perhaps postulate it. There's a hidden variable, the left of particles know how they'll be measured. So, that means.

641
01:14:54.779 --> 01:15:05.725
That when the 1st one's mentors spending 1 direction, that's it has inherent property of that vertical. And therefore, the other 1 has a property it shows it will be measured the other way.

642
01:15:08.125 --> 01:15:18.024
So belt, partially there's something called bell's inequality and he showed that whenever this inequality is not satisfied, it's impossible for there to be hidden variable that accounts. For in this case, it's been a articles.

643
01:15:21.805 --> 01:15:22.225
All right,

644
01:15:22.255 --> 01:15:27.444
so at the heart of bells theorem as mentioned is bells any quality and this,

645
01:15:27.444 --> 01:15:32.154
any quality is actually just a relatively simple fear that has to do with counting,

646
01:15:32.545 --> 01:15:32.814
which,

647
01:15:32.814 --> 01:15:34.255
I think is pretty surprising,

648
01:15:34.255 --> 01:15:37.675
considering the implications that it has for our understanding of universe.

649
01:15:38.515 --> 01:15:46.314
So, what Belden equality says is, say, you have 3 binary variables a. B and C. so they can be true or false.

650
01:15:46.914 --> 01:15:59.904
And what those there are any quality says, is that the size of the set, and not be, which is reading that diagram there, plus the size of the B and C which is the blue 1.

651
01:16:00.630 --> 01:16:05.454
Has to be greater than or equal to the size of the set and not see,

652
01:16:05.994 --> 01:16:18.744
hopefully these Venn diagrams will be to visualize that and hopefully we should also make it apparent why this has to be true because the green area is entirely encompassed by the right in the blue areas combined,

653
01:16:19.375 --> 01:16:22.675
so it cannot possibly be larger than the,

654
01:16:22.675 --> 01:16:22.914
uh,

655
01:16:22.975 --> 01:16:23.664
the red and blue.

656
01:16:25.345 --> 01:16:33.265
It's important to note that this is a fact, this is a fact, right?

657
01:16:33.265 --> 01:16:47.305
It's always true for any 3 binary variables and that's going to be very important for how we can disprove the fact that the hidden variables exist while we're on the slide.

658
01:16:47.305 --> 01:17:02.244
I would also like to mention that the original belly any quality is usually written differently as correlations, rather than set sizes. But that is very convoluted. It would've taken me several minutes to explain.

659
01:17:02.274 --> 01:17:09.595
So, I tried to simplify it down to this thing where to make it easier to understand. But if you're curious, you can take a look at page as an explanation.

660
01:17:10.409 --> 01:17:14.670
Right.

661
01:17:14.670 --> 01:17:20.520
So, how can we take those inequality and apply it to the quantum world?

662
01:17:20.520 --> 01:17:29.399
We can use those inequality along with some experimental data that can be collected to understand the basis that is built here.

663
01:17:29.399 --> 01:17:38.454
So those relies on approved by contradiction. So what we're going to do is we're going to suppose that there are hidden variables. Right?

664
01:17:38.454 --> 01:17:51.685
And every photon that exists has some hidden variable that determines whether it'll pass through any polarized filter and we're going to have 3 polarized filters that will call a B and C.

665
01:17:52.164 --> 01:17:59.545
and each of these filters will have a different organization. So, based on all of these assumptions, we should have some variables.

666
01:18:02.069 --> 01:18:09.659
That will deterministically tell us whether any given photon will pass through any 1 of these filters.

667
01:18:09.659 --> 01:18:22.319
So, as the example here shows, if we have a full time, where is true is true is false, it should be able to pass through filters a, and B, but Nazi.

668
01:18:22.319 --> 01:18:26.460
Now, if you can go to the next slide said.

669
01:18:26.460 --> 01:18:36.564
If we were to actually conduct this experiment, we would see something like the following. And if you've taken physics to, at hopefully you've seen this experiment before. I know I had it when I took physics too.

670
01:18:37.614 --> 01:18:51.534
And if you subscribe to the hidden variable theory in that, all of the, the photons in these experiments have hidden variables that will determine whether they pass through any of these filters. You should find this pretty disturbing.

671
01:18:52.140 --> 01:19:06.180
Because here, all we've done between these 2 experiments is add in filter B in between Nancy and filter B isn't producing any additional photons right? We're simply adding something.

672
01:19:06.180 --> 01:19:12.960
That blocks both times, and yet, and more of the photons are getting through this stack of filters.

673
01:19:14.039 --> 01:19:26.430
So, if none of the photons are passed through both a, and C, and the left setup, the question becomes, why can they pass through both a, and C in the right setup?

674
01:19:26.430 --> 01:19:39.989
And mathematically to put this in terms of bells inequality, this is what that comes in. If we were to measure the intensity of the light, it's passing through these filters in order to calculate the number of photons that are making it through.

675
01:19:39.989 --> 01:19:53.635
We would find obviously on the left none of the photons that make it through a, are making it through. See so our set size of a, and C not is 100% of the photons passing through a here.

676
01:19:53.664 --> 01:19:56.185
When I did these percentages.

677
01:19:56.185 --> 01:20:10.225
This is just the percentage of photons that are passing through a initially just because if you don't assume that, then you're just multiplying everything by the fraction of photons that just makes maximum and on the right side.

678
01:20:10.225 --> 01:20:21.175
You'll find that 15% of the photons that pass through a, are blocked by B and then of the 50% that remains another 50% of that is blocked by C.

679
01:20:21.175 --> 01:20:28.194
so we have 50% of protons and not be and 25% of the 3rd times and B not C.

680
01:20:31.050 --> 01:20:36.090
And what we end up with, if we try to put this into equality.

681
01:20:36.444 --> 01:20:49.314
Is we have 100% is less than or equal to 75% which is obviously not true. So, what does this mean? It means that our initial assumption, right?

682
01:20:49.314 --> 01:21:00.654
That there are existing variables. That allow us to categorize all of the photons in this experiment into a B. and C, depending on whether they pass, the filters cannot be correct.

683
01:21:03.930 --> 01:21:07.710
And this experiment.

684
01:21:07.710 --> 01:21:11.340
Is it has some flaws to it? Right? Um.

685
01:21:11.340 --> 01:21:18.390
There are certainly loopholes to this experiment and for instance, you could argue that. Well.

686
01:21:18.390 --> 01:21:31.140
Maybe the reason things are so weird is because somehow, when a photon passes through the filter, that filter changes its internal state, the hit variables, right?

687
01:21:31.140 --> 01:21:36.090
So, this on its own, can't.

688
01:21:36.090 --> 01:21:49.560
The possibility in variables, but this is hopefully an example that everyone should be familiar with and it gives the idea of how these experiments are.

689
01:21:50.034 --> 01:22:02.454
Performed and how they can be used to show them what bills their, and claims is actually true if you didn't go to the next slide said, just want to give an example here a little bit better of a way to do it.

690
01:22:02.454 --> 01:22:15.774
And this is a lot closer to how these experiments are actually done is to try to get around to that argument that I just presented rather than taking a single photon and passing it through a stack of filters.

691
01:22:16.164 --> 01:22:31.045
What you would do is you get 2 entangled photons and you pass them individually through a single filter each and that way you can no longer make that argument that the filter might just measuring the polarization might actually

692
01:22:31.045 --> 01:22:32.364
change those hidden States.

693
01:22:32.664 --> 01:22:39.204
And as it turns out this produces exactly the same results as the experiment that we just talked about.

694
01:22:39.869 --> 01:22:45.300
Additionally, what you can do with this, and I think we're going to talk about this bill on the next slide. Is that.

695
01:22:45.300 --> 01:22:58.500
You can take these 2 protons and move them really far away from each other. And that way you can show that unless they're violating locality that they can't be communicating with each other either.

696
01:23:01.104 --> 01:23:11.725
So, expanding on that there's several possible loopholes that are brought up in regard to these experiments to prove, or disprove bell serum.

697
01:23:12.204 --> 01:23:19.795
So the 1st, 1 is called Super determinism and unless we can do about that that's the idea everything's predetermined and retraced this matter.

698
01:23:19.795 --> 01:23:24.175
So the fact that somebody performance experiment that defence measuring a certain way,

699
01:23:24.774 --> 01:23:25.494
already happened,

700
01:23:27.925 --> 01:23:33.085
that's kind of a concept of a global variable or global variables and unfortunately,

701
01:23:33.864 --> 01:23:36.444
there's not really a way to test for that or experiment it.

702
01:23:36.444 --> 01:23:49.914
So ignore it. There are 2 other loopholes that exist in these experiments versus so your detection be far enough apart and then taking close enough to get there in time to ensure that detection isn't influencing together.

703
01:23:50.189 --> 01:24:01.859
If you just a meter apart, that's very little time difference for, uh, to allow for your detection to be made before communication would happen.

704
01:24:02.935 --> 01:24:15.234
There's something called the detection mobile, so, in certain cases, your particles may always be detected and therefore only you're only disproving upon to a subset of all the particles.

705
01:24:15.685 --> 01:24:24.685
Perhaps all the particles still do exhibit random behavior that would satisfy a 1000 inequality. How so.

706
01:24:24.899 --> 01:24:38.364
Several tests, or there's been many tests uh, especially the ones, like, listen like media, but most have some possible violation of either locality and or the detection nipple. However, there was a test published in nature. General 2015th projects.

707
01:24:38.364 --> 01:24:53.154
Both of these loopholes they rejected by separating particles by 1280 meters this gives them 4.7 microsecond time window for measurements. And they have a characterization of their measurement process to show that terrible. Within that time period.

708
01:24:53.154 --> 01:25:03.864
They then address detection loophole by using a form of a event ready signal and that basically allows them to check the.

709
01:25:09.479 --> 01:25:14.640
Uh, superposition was collapse.

710
01:25:14.640 --> 01:25:21.180
Was actually collapse and that both particles were actually detected. So it allows them to exclude any failed.

711
01:25:22.555 --> 01:25:36.805
Um, so, as a result based on this experiment least, it seems to be that what, the locality loophole, and the detection loop over rejected and therefore it's most likely true that those inequality or certain holds, and there are no hidden variables.

712
01:25:37.135 --> 01:25:40.194
And we have some, uh, some links.

713
01:25:42.810 --> 01:25:49.409
That way they get in there. Oh, all right. They have any questions.

714
01:25:50.550 --> 01:25:55.800
Well, thank you. I learned a walk, so.

715
01:25:55.800 --> 01:25:59.819
Weird things now.

716
01:25:59.819 --> 01:26:05.310
Right.

717
01:26:05.310 --> 01:26:09.689
Now, running late actually, I, I'm.

718
01:26:09.689 --> 01:26:14.880
Responsible for a lot of that and I want to be fair to, um.

719
01:26:14.880 --> 01:26:21.060
Cohen Davis, so question to call of, to other people. Are you willing to.

720
01:26:21.060 --> 01:26:26.310
Continue meeting, or do you have to get awake on a conflict and to colon? Of course are you.

721
01:26:26.310 --> 01:26:35.220
Willing to talk if not, I'll give you your choice of any future day to present on Thursday or next week. Accurate option.

722
01:26:35.220 --> 01:26:47.430
So, yeah, I'm, I'm not going whatever it's up to everyone else, depending on what they okay. Are people willing to today?

723
01:26:48.689 --> 01:26:53.279
Okay, well, thank you, then call him so.

724
01:26:53.279 --> 01:27:04.020
I can stay right and okay, so let's hear about stuff. In theory. We could actually build it.

725
01:27:04.020 --> 01:27:15.930
Right. I can see you can see your slides. Oh, cool. So, for the next few minutes here.

726
01:27:15.930 --> 01:27:24.659
I'm just going to be going through some of the methods and theories in how 1 can implement quantum computing hardware.

727
01:27:26.640 --> 01:27:34.680
Now, before I get into specific implementations, I think it's important to at least consider.

728
01:27:34.680 --> 01:27:39.329
Some of the factors that 1 would have to think about when implementing a quantum computing system.

729
01:27:39.329 --> 01:27:50.850
I won't go through all of these in interest of time, but I at least want to highlight that last 1 there, which is the ability of your system to mitigate the effects of deacon parents.

730
01:27:50.850 --> 01:27:56.039
I know John already went through a lot of that, but I just want to highlight real quick.

731
01:27:56.039 --> 01:28:02.970
When talking about coherence you're referring to, how your system, how your chew bits.

732
01:28:02.970 --> 01:28:08.970
Begin to interact with their environment and entangled within our environment over time.

733
01:28:08.970 --> 01:28:16.079
So, for example, say, you have a series of electrons, which you're using for your 2 bits.

734
01:28:16.079 --> 01:28:19.140
Over time those electrons will start to.

735
01:28:19.140 --> 01:28:23.819
Interact with other electrons in the environment around them.

736
01:28:23.819 --> 01:28:36.210
And when this happens, you lose control over the state of your system, and your data isn't really useful at that point because you can't account for all of these entanglement with the environment around your cube.

737
01:28:36.210 --> 01:28:45.869
So the longer your system can remain coherent, the better, the more quantum computations you can actually perform.

738
01:28:45.869 --> 01:28:54.270
So, now we can start to get into specific implementations and I'll start with the IoT quantum computer.

739
01:28:54.270 --> 01:29:03.239
And here, we're using some type of medical had the 1 in the picture on the right there is for really embraced making stuff. The metals like the calcium.

740
01:29:03.239 --> 01:29:11.250
But you're bringing that metal into a gaseous state, then you're stripping it some of its electrons to make them ions.

741
01:29:11.250 --> 01:29:17.489
And those plans being charged, obviously you can now manipulate them with in electromagnetic field.

742
01:29:17.489 --> 01:29:26.939
So, at that point, you can use a laser to excite the electrons on these ions into higher energy orbitals.

743
01:29:26.939 --> 01:29:32.399
So, now you have a, an excited state for those ions versus the normal ground state.

744
01:29:32.399 --> 01:29:38.760
So, here, your ground state would be your 0T state in your excited state would be your 1 state.

745
01:29:38.760 --> 01:29:51.930
And that's where your attributes are in this case. So, as far as actually measuring the states of your achievements, you have this intermediate energy level that sits between that 0T and 1 energy state.

746
01:29:51.930 --> 01:29:59.579
And when you hit when you hit your ions with the proper.

747
01:29:59.579 --> 01:30:09.689
Energy pulse from your laser if the ion returns to its ground state soon, after in the midst of photon, don't know that it was in its ground state.

748
01:30:09.689 --> 01:30:14.550
And if not, you'll know if you don't see that photon emission, you'll know that you're on.

749
01:30:14.550 --> 01:30:20.760
Or your was in its excited state so as you're performing quantum computation on the system.

750
01:30:20.760 --> 01:30:26.760
You were looking for either the mission or the lack of a mission of photons.

751
01:30:26.760 --> 01:30:34.859
And so, with the system like this, you have the benefit of longer coherence times and these systems are fairly reliable.

752
01:30:34.859 --> 01:30:46.170
And as far as reliability, you're looking in the range of around 99% versus other quantum computing systems, which are typically around 90 to 95%.

753
01:30:46.170 --> 01:30:59.670
Unfortunately, these systems are relatively slow as far as gate operations and it's a bit unclear at the moment how you would scale these types of systems up to a significant number of Cubics.

754
01:31:01.710 --> 01:31:07.979
So, now we can move on to our 2nd type of implementation here, which is based upon linear optics.

755
01:31:07.979 --> 01:31:12.000
And here, we're using photons as our 2 minutes.

756
01:31:12.000 --> 01:31:21.060
And the polarization of these photons is what corresponds to your quantum states so horizontal versus vertical polarization.

757
01:31:22.260 --> 01:31:33.960
And in this case, you would use filters to initial attributes to your desired state. And then you can use things like mirrors beams letters, etc to do your a date manipulation.

758
01:31:33.960 --> 01:31:39.600
Now, the great thing about this type of implementation is that you can.

759
01:31:39.600 --> 01:31:44.970
You can have these optical circuit boards, which there's a picture of 1 of those circuit boards.

760
01:31:44.970 --> 01:31:49.649
Down below there, because of how, like, travels.

761
01:31:49.649 --> 01:31:53.489
And slight change in here, but.

762
01:31:53.489 --> 01:31:57.838
Personally, I would predict if you were to see any kind of.

763
01:31:57.838 --> 01:32:02.548
Commercially available quantum computing products beyond just the.

764
01:32:02.548 --> 01:32:06.479
Typical research and scientific use.

765
01:32:06.479 --> 01:32:14.609
I would think it would be this method within the next couple of decades, because it's obviously easier to integrate something like an optical circuit board into.

766
01:32:14.609 --> 01:32:22.588
Some of our existing technology infrastructures, then some of the other methods that I've talked about and what we're talking about here.

767
01:32:24.088 --> 01:32:32.128
Now, unfortunately, photons are a bit difficult to entangle, which makes performing date operations a bit difficult.

768
01:32:32.128 --> 01:32:35.639
However, that's also a bit of a positive at the same time.

769
01:32:35.639 --> 01:32:39.418
Because your system can maintain its coherence for longer.

770
01:32:39.418 --> 01:32:44.429
As your photons aren't entangling with the environment quite as easily.

771
01:32:47.338 --> 01:32:52.979
Okay, so now we get to the method, which is a nuclear magnetic resonance based quantum computing.

772
01:32:52.979 --> 01:32:58.828
And in the past liquid state more was the more popular method.

773
01:32:58.828 --> 01:33:05.519
Where are you with these larger molecules? He would suspend them into fluid and then you would use to.

774
01:33:05.519 --> 01:33:09.779
Manipulate a specific atoms within those molecules.

775
01:33:09.779 --> 01:33:15.269
And over time, we've seen more of a transition into solid state in Omar.

776
01:33:15.269 --> 01:33:18.359
Which are on the right there. You can see.

777
01:33:18.359 --> 01:33:22.948
The diamond lattice with a nitrogen vacancy in perfection.

778
01:33:22.948 --> 01:33:28.288
And some types of solid state would use a, a lattice like that.

779
01:33:28.288 --> 01:33:35.458
And you would manipulate the spin of that nitrogen atom within the lattice. And that would be your Cuba. It.

780
01:33:36.689 --> 01:33:47.338
Now, our base quantum computing in general has longer coherence times on the scale of 1 to 10 seconds. Sometimes even longer in very special circumstances.

781
01:33:47.338 --> 01:33:58.198
Those solid state and Amar generally has better coherence times than liquid state. So that's why you're seeing more of a movement. The solid state.

782
01:33:58.198 --> 01:34:10.048
And aside from that solid state, and Amar has it, it's generally easier to do more precise cubic manipulation on those solid state Cupid than in a liquid state.

783
01:34:10.048 --> 01:34:20.219
Unfortunately, because you're taking an average over a large number of molecules with systems like these, rather than just focusing on 1 particular, keep it.

784
01:34:20.219 --> 01:34:28.229
This signal to noise ratio with systems. Like, these are a little bit more on the poor side relative to some of our other solutions.

785
01:34:28.229 --> 01:34:36.838
So, now we get to our 4th big method here, which is the Super conductor based quantum computer.

786
01:34:36.838 --> 01:34:42.418
And this is what you really hear about when you hear about companies like Google and IBM.

787
01:34:42.418 --> 01:34:49.828
Doing quantum computing research now in this case, she bits implemented with these things called.

788
01:34:49.828 --> 01:34:55.078
Joseph SIM, junctions and here you have 2 pieces of.

789
01:34:55.078 --> 01:34:58.078
Superconducting wire and.

790
01:34:58.078 --> 01:35:03.448
Except in between those ends, you have this been insulator.

791
01:35:03.448 --> 01:35:08.519
And as you bring those pieces of superconducting wire down to.

792
01:35:08.519 --> 01:35:21.238
Within Miller, Calvin of absolute 0T electrons in each of those ends of wire begin to flow extremely easily and they'll quantum tunnel through the insulating layer.

793
01:35:21.238 --> 01:35:30.328
And the back and forth between those wire ends it a rate of billions of times per seconds. So, in the gigahertz range.

794
01:35:30.328 --> 01:35:37.979
Now, in this case, your cubic States are actually the 2 lowest frequency.

795
01:35:37.979 --> 01:35:50.788
Of the current between those 2 ends. So obviously we've talked a bit about implementations and they think that this kind of technology is highly scalable outline. I know we've touched on.

796
01:35:50.788 --> 01:35:55.889
How they're looking to implement a 1000 plus cubic system within the next couple of years.

797
01:35:55.889 --> 01:36:03.208
And they've already designed a, a refrigeration infrastructure that would be suitable for.

798
01:36:03.208 --> 01:36:06.929
A 1M cubic system a theoretical 1M, keep it system.

799
01:36:06.929 --> 01:36:12.269
So, they definitely think that this technology is scalable, which is a really big plus for this method.

800
01:36:12.269 --> 01:36:17.698
Unfortunately, it does suffer from a lower coherence times. Obviously.

801
01:36:17.698 --> 01:36:31.859
That's why you need these robust refrigeration infrastructures, because you need to maintain that for parents as long as possible. So, as you say, improvements with those infrastructures, you'll see more improvements in the coherent of these systems.

802
01:36:31.859 --> 01:36:40.469
And then over on the right there, you can just see 1 of the abm's 1st, commercially available quantum systems, which was 20 Cubics.

803
01:36:43.229 --> 01:36:48.509
So, there are a huge number of variations on.

804
01:36:48.509 --> 01:36:52.019
How you can actually implement quantum computing.

805
01:36:52.019 --> 01:36:56.519
And many of them are just navigations on methods that party covered.

806
01:36:56.519 --> 01:37:00.238
I just wanted to highlight a couple of interesting ones that I found.

807
01:37:00.238 --> 01:37:04.859
Which were quantum computers, which in that case, your.

808
01:37:04.859 --> 01:37:10.439
You're leveraging these 10 states of electrons on quantum particles.

809
01:37:10.439 --> 01:37:15.719
And there's also the king quantum computer, which is a variation on solid state and mark.

810
01:37:15.719 --> 01:37:21.779
Which is a Silicon rat lattice rather than a a diamond lattice that I talked about previously.

811
01:37:21.779 --> 01:37:26.788
And that's being highly in pursued and investigated in Australia currently.

812
01:37:26.788 --> 01:37:32.248
But, yeah, there's a huge number of variations on the methods I've already gone through.

813
01:37:32.248 --> 01:37:40.048
And at this point, it's difficult to rule out any particular method because they're obviously progressing at different rates.

814
01:37:40.048 --> 01:37:43.229
And different methods could see.

815
01:37:43.229 --> 01:37:46.948
Let's see different breakthrough is different applications to.

816
01:37:46.948 --> 01:37:59.038
To different different bodies of science so it will be interesting to see moving forward. Obviously there's a big push for superconducting based quantum computing.

817
01:37:59.038 --> 01:38:13.229
From a lot of the big big companies doing this research, but yeah, it'll be interesting to see moving forward what she really read it out. And what methods become the most dominant industry.

818
01:38:13.229 --> 01:38:20.038
So, yeah, so that's pretty much it. And then I have references here.

819
01:38:20.038 --> 01:38:23.698
Hello? Hello?

820
01:38:23.698 --> 01:38:29.548
Any questions, so you think will be the waiter touch the big.

821
01:38:35.009 --> 01:38:38.309
Oh, sorry. Okay. Who do you think will be the winner?

822
01:38:38.309 --> 01:38:42.418
Yeah, because they're big or oh.

823
01:38:42.418 --> 01:38:45.809
That's a good question. I think there is.

824
01:38:45.809 --> 01:38:50.189
Definitely a push from the big companies right now.

825
01:38:50.189 --> 01:38:53.729
In that in quantum computing, and IBM certainly seems to have.

826
01:38:53.729 --> 01:38:58.529
A robust warranty department, and the resources to make that happen.

827
01:38:58.529 --> 01:39:04.529
We certainly seem to be very deliberate and a half plan laid out.

828
01:39:04.529 --> 01:39:10.588
And, like I mentioned, they've already designed that massive refrigeration infrastructure so they're planning for.

829
01:39:10.588 --> 01:39:21.418
Much bigger work down the road. Okay. Now as far as superconducting at least IBM could certainly pull ahead, but again different.

830
01:39:21.418 --> 01:39:32.458
Different researchers are doing or pursuing different types of implementations and really, you can see a huge advancement suddenly in any 1 of these methods moving forward. So, yeah, it'll be interesting to see.

831
01:39:32.458 --> 01:39:39.269
Small guy might win. Okay. Well, thanks. Everyone. So we'll see the 2nd.

832
01:39:39.269 --> 01:39:46.139
You know, session on Thursday, and if you could send me your, your videos or slides and if you're.

833
01:39:46.139 --> 01:39:52.229
If you're agreeable, I'll post them on the Web site if you don't like that I won't. That's totally optional. So.

834
01:39:52.229 --> 01:39:56.368
I'll put that on so, so see you Thursday.

835
01:39:56.368 --> 01:39:59.849
I'll stay around for a few minutes in case. There's any questions.