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Time Running Out for Public Key Encryption
holy_calamity writes "Two research teams have independently made quantum computers that run the prime-number-factorising Shor's algorithm — a significant step towards breaking public key cryptography. Most of the article is sadly behind a pay-wall, but a blog post at the New Scientist site nicely explains how the algorithm works. From the blurb: 'The advent of quantum computers that can run a routine called Shor's algorithm could have profound consequences. It means the most dangerous threat posed by quantum computing - the ability to break the codes that protect our banking, business and e-commerce data - is now a step nearer reality. Adding to the worry is the fact that this feat has been performed by not one but two research groups, independently of each other. One team is led by Andrew White at the University of Queensland in Brisbane, Australia, and the other by Chao-Yang Lu of the University of Science and Technology of China, in Hefei.'"
More like the Chinese government wants to break the encryption so they can more easily hack other governments data. They just post it under "Research".
This doesn't break "public-key cryptography". Even if you could build a Shor-factorization machine big enough to use against real-world keys (and that's a *big* if), it's only good against RSA. Elliptic-curve cryptosystems, for example, would be entirely unaffected...
WRONG!!!!!
Actually I'll be polite because you're a girl.
You are misinformed. Shor's algorithm finds group orders, which suffices both to factor RSA keys and break discrete log systems, which include elliptic curves. Other posts here have explained this in more detail.
Anyway, it's a long way from running Shor's algorithm to factor 15 to being able to factor a 4096-bit RSA key. Remember that because of the no-cloning theorem you can't build a flip-flop for qubits, so quantum circuits are all combinatorial logic. Applying Shor's algorithm to real-world RSA keys would require building a complete modular exponentiator combinatorially out of quantum logic gates... blah, blah, blah.
Again you are misinformed. You don't build a combinatorial circuit. You have a bunch of qubits which stay put, and you use external influences like electromagnetic pulses to change their state. In this way you can lead the whole qubit "register" through a series of transformations that implement whatever quantum or non-quantum transformation you desire, including modular exponentiation. The specific circuit implemented is not hard-wired as with a combinatorial approach, it is programmed via the particular series of transformation applied to the array of qubits.
If you had more than a passing knowledge of quantum mechanics, you'd know that superposition is empirically observable.
Yeah, right. The QC hoaxers and bullshitters will always win more grant money as long as they have Star-trek physics fans like you on their side. Why don't you all jump in your wormhole spaceships and zip into a parallel universe? Oh yeah, I almost forgot. Parallel universes. Isn't that the explanation that the crackpot lunatic and quantum computing champion, David Deutsch, is using for QC? Yes sir. Billions and billions of parallel universes that nobody can ever observe. I guest impiricism is only needed when you crackpots are attacking the other religions, eh? Yeah, that's it. A stupid nerd religion is what you have.