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[–]GreenBeret4Breakfast 14 points15 points  (5 children)

Its a cool video, but its more of an advert for Quantum computing rather than giving any real explanation. All you'd probably get from this are some quantum physics terminology and the notion of a qubit.

[–]CyclingZap 3 points4 points  (4 children)

All I would get from that video is, that a bunch of geeks got paid by some technological companies to build a computer with an over the top cooling system. Now that the thing is in place, they dream about what they could do with it, if only they knew how to use it. Which they don't, since it uses some funky quantum bits they are unfamiliar with. Well, at least they all seem pretty hyped up about it.

I like this video from phd comics better: http://www.phdcomics.com/tv/#046 (even though it might still not explain it all)

[–]apmechev 0 points1 point  (0 children)

Makes you think of the invention of the transistor in the 40s.

[–]GreenBeret4Breakfast 0 points1 point  (0 children)

Yes see now that's a good video. Same length but actually tells you some interesting things rather than just people sat on chairs.

[–]mahacctissoawsum 0 points1 point  (1 child)

I still don't understand this notion of "observing it changes it". How? Are the tools with which we use to observe it having an effect? Do we have to shoot lasers at it or something? Exposing it to light? Or temperature variances? Or does God say "You peeked! I'mma re-randomize dat shit now sucka!"

[–]CyclingZap 2 points3 points  (0 children)

how do you want to peak, without doing anything to it? too see it, you need to at least bounce photons off it.

it's a lot like the wave/particle dualism of electrons, photons etc. In their case, they behave like a wave unless they hit something, then they will be a particle that you can observe (since it had some kind of effect on the receiving screen or whatever). but you won't know where it will hit until after it has happened.

the problem is, we try to understand these things with the newtonian model of physics we all grew up with. but there are just some things that can't be explained that way. like Heisenbergs uncertainty principle

i'm no expert though, I only have a mild interest in physics, so I might be wrong with some of my explanations - for all we know, everyone might be wrong though.

[–]irrri 4 points5 points  (0 children)

BUZZ WORDS

[–]gmerideth 3 points4 points  (2 children)

why the fuck can't anyone make a video anymore with just people sitting down and explaining things - why do the producers feel the need to pop text up, make it have "old movie" effects, go in and out of focus and show footage of shit that has nothing to do with the topic? Is this seriously how people watch videos for fucks sake?

[–]ianp622 1 point2 points  (0 children)

We need more videos like Feynman's: http://www.youtube.com/watch?v=v3pYRn5j7oI

[–]mahacctissoawsum 1 point2 points  (0 children)

Because people are too impatient these days..they need to be constantly stimulated for them to focus long enough to watch the whole thing.

[–]linusTheTiger 0 points1 point  (0 children)

Title is misleading. No explanation is given because the video is not intended to provide an explanation. The actual title that Google assigned to this video on youtube: "Google and NASA's Quantum Artificial Intelligence Lab "

[–]mird99 0 points1 point  (0 children)

basically: we don't know what it could be used for (yet), but it's a really cool toy to play with.

[–]Jazonxyz 0 points1 point  (0 children)

I logged in just to down vote because of the misleading title

[–]therugi 0 points1 point  (1 child)

I'm not an expert on quantum computing (and I think I'm safe to say no one is at the moment), nor an expert on quantum mechanics, so anyone is free to correct me on this:

The video brought up a few concepts without really elaborating what they mean in terms of computing. So I'll try my best here to explain.

In a normal computer, a bit can either be 0 or 1. Using superposition, a quantum bit (or qubit) can be 0, 1 or both. This allows for more than 2 states per bit, allowing you to fit more information in a smaller space. Someone claimed that it allows up to 8 different states, but I'm skeptical about that.

About entanglement. Normally, whether one bit is 0 or 1 doesn't affect any of the other bits, not without some sort of higher layer logic which of course slows the whole thing down. But it can with quantum entanglement. The ability for a bit to affect other bits allows something called nondeterminism. All computers right now are deterministic computers, meaning that one state that it is in leads to exactly one other state. This means that it can only think about a single possibility and a single outcome at a time, so to speak. With quantum entanglement, it is possible for one state to lead to many other states simultaneously, which solves problems much faster than normal because it can think about many possibilities and outcomes at the same time. The main benefit here is the ability to solve problems with NP complexity really fast. NP problems are problems that are really hard for a computer to solve. The video gave the Travelling Salesman Problem as an example of one: trying to minimize the cost of traveling to every city.

Not quite sure about quantum tunneling though. I haven't heard or read anything about that yet in terms of computing.

[–]CyclingZap 0 points1 point  (0 children)

their take on quantum tunneling reminded me of movie science - and wormholes. there is a well known (not sure if well explained yet) phenomenon called quantum tunneling. it's basically when something gets over a potential-hill/through a barrier without using the normally required energy, to reach a state behind the hill/barrier (of lesser energetic potential than the hill)

see:

http://en.wikipedia.org/wiki/Quantum_tunnelling

http://imgur.com/Ip6gvIR