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Michael Nielsen's Free Video Courseware On Quantum Computing
New submitter quax writes "Michael Nielsen, who co-authored the book on Quantum Computing, released a set of short video lectures on his blog this summer (link to Google cache). They make a great introduction to the subject. But here's the catch: Due to other work responsibilities, he stopped short of completing the course, and will only complete it if he sees enough interest in the videos. Let's show him some numbers."
I misread and thought that said Mike Nelson. Got excited about a Rifftrax about quantum computing.
Let's have this post as a placeholder for all the Heisenberg and Schrodinger superposition jokes that show up in every single quantum computer story. Thanks!
Do you want the jokes or not? You can't have it both ways.
In quantum mechanics, you can. But only as long as you don't look.
The Tao of math: The numbers you can count are not the real numbers.
I don't know if you are serious or joking here, but you could definitely stand to take this course. You seem to be under a lot of misconceptions about what quantum computing can do.
Quantum, or more specifically quantum mechanics will be the next Major human revolution.
Quantum mechanics is used all the time by lots of devices you use. Small transistors work because of quantum mechanics. Lasers work off of lots of quantum mechanics. LEDs work off of quantum mechanics. Etc. Etc. There's nothing new about using quantum mechanics.
and Quantum Transceivers to that all those Optical SFPs in your switches and routers won't need cables anymore
This and almost every other application you mention is complete nonsense. Quantum mechanics does not allow you to transmit information in special ways. Entanglement doesn't let you get away with that. (This is as far as we are aware, ignoring for now certain very interesting results from CERN that are likely to be incorrect and are still being checked over. Even if this is correct, it is unlikely to allow actual FTL or the like but rather be other interesting new physics. And calling that simply quantum mechanics would be misleading.)
You can do things with quantum computers that you can't do with conventional systems. What we mean by quantum computers are not computers that use quantum mechanics in general (since they all do that) but computers that can take advantage of entanglement. This allows certain processes to occur much faster than they can with a conventional computer. For example, operations with Fourier series become a lot easier, and it becomes much easier to find the period of a given function. This translates into being able to do certain classes of problems much faster.
For example, it seems that using something called Shore's algorithm ahref=http://en.wikipedia.org/wiki/Shor's_algorithmrel=url2html-18175http://en.wikipedia.org/wiki/Shor's_algorithm> you can factor integers faster on a quantum computer than you can on a classical computer. This is a big deal, but even this requires a lot of caveats. First, we can't actually prove that this is better than the best classical factoring algorithms. In most interesting formulations of this claim, it depends on the assumption that factoring is not in P, a claim that is strictly stronger than the claim that P != NP http://en.wikipedia.org/wiki/P_versus_NP_problem (it is possible that factoring lies in P but one gets a large speedup of like Klogn or something like that to the quantum system. This is possible, but fundamentally less interesting and less useful.)
There are other specific similar examples, and even a handful where we can prove that the quantum version is really better than any classical version. The most prominent such example is Grover's algorithm. http://en.wikipedia.org/wiki/Grover's_algorithm. This algorithm allows you to search unsorted databases much faster than you can in a conventional setting. That's a really useful but ultimately high restrictive use.
Now, in fairness to you there are some uses of entanglement and other interesting quantum phenomena which don't rely on quantum computing per se. So you may have been thinking of those. But those don't allow what you seem to think they can do either! The closest to anything like that is quantum encryption, which makes a system of encryption that is essentially unbreakable as long as our understanding of the laws of physics are correct. That's pretty cool but even that has its own limitations, and it turns out can in some specific circumstances be broken http://www.sciencedaily.com/releases/2008/05/080508143107.htm. There are other interesting technologies out
I can't use it anymore though. Every time I've tried to read from it, my cat dies.
Something must be wrong with your drive. Your cat should only die half the time.
Actually quantum mechanics already is the previous revolution. Lasers are quantum. Semiconductors are quantum. Without quantum mechanics, our computers would still be big monsters of tubes with the power of a pocket calculator. The giant magnetoresistance, which is the base of our high-density hard disks, is a quantum effect. Without quantum mechanics, the whole information technology revolution could not have taken place.
That's not to say that quantum information wouldn't be a huge step from that. It's applying quantum mechanics to the information itself, instead of "only" using it to improve the handling of classical information. However, reducing the impact of quantum mechanics to quantum information vastly underestimates its importance. Even if the quantum computer should turn out to be impossible for some reason, quantum mechanics will not become useless. Almost all of our modern technology is based on it.
The Tao of math: The numbers you can count are not the real numbers.
I can't use it anymore though. Every time I've tried to read from it, my cat dies.
Something must be wrong with your drive. Your cat should only die half the time.
Actually, on average only every 18th time the cat should die. Yes, half the time the cat will lose its life. However, everyone knows that cats have nine lives.
The Tao of math: The numbers you can count are not the real numbers.
It's idiotic to prove that. The right way to do things is define them as inner product preserving and then it's immediate that they are length preserving.