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IBM Builds A Limited Quantum Computer

Posted by chrisd on from the soon-your-pgp-key-will-be-useless dept.

phr1 writes "IBM has announced and Yahoo has noted that the first working implementation of Shor's factoring algorithm. Using NMR techniques they built a seven-qubit quantum computer and factored the number 15 into the factors 3 and 5. This is by far the most complicated quantum computation ever done. It's quite an amazing feat--many people thought quantum computing was just a theoretical curiosity and Shor's algorithm could never be implemented in practice."

5 of 316 comments (clear)

  1. Re:if a quantum computer takes the same time by Anml4ixoye · · Score: 5, Interesting
    Mainly because of the number of molecules it takes to perform that feat. "IBM chemists designed and made a new molecule that has seven nuclear spins" - exactly enough to solve the simple factor. You need many more spins than that to perform complex calculations.

    But once the molecules are put together and they can control them properly, then nothing really stops it. That is why they say that a fundamental change in cryptography is on the horizon.

    --
    Random Musings
  2. similar has been done before by Phork · · Score: 3, Interesting

    2 years back i heard someone(i belive it was bruse schneir), say that the NSA or los alamos had built a quanum computer, and it could factor the number 7, down to 1 and 7, not to hard. but still an impressive feat.

    --
    -- free as in swatantryam - not soujanyam.
  3. Re:Frightening implications by actappan · · Score: 3, Interesting
    Good science projects only get the shaft if they have nothing to do with:

    • Killing the other guy in new and interesting ways.
    • Reading the other guy's mail.
    • Stealing from the other guy.
    • Reading your own guys' mail.
    • Stealing from your own guys.
    • Killing your own guys in new and interesting ways.
    --
    \Drew National Data Director, John Edwards for President
  4. Re:Frightening implications by El_Nofx · · Score: 3, Interesting

    1. The us government does not have an unlimited budget.

    2. Most meaningful research comes from the private sector (bell labs and the like) with a few exceptions (Darpa)

    3. Even if the government had quantum computer level encription it couldn't get it's self organized enough to use it for more then maybe presidential level communication.

    --
    It's not the OS it's the user that sucks. If it's user friendly, you get stupider people. - clinko
  5. You're exactly right and wrong! by HiredMan · · Score: 5, Interesting

    You're right that the NSA knew about Differential Cryptanalysis years before anyone. I extrapolated this largely using the same facts - but if you read _AC_ carefully they openly acknowledge this.

    But you're wrong in the fact that DES IS resistant to DC. The bit S-box design the NSA gave IBM are designed to make it STRONGER against DC NOT weaker.

    "As in choosing the key length , another of the NSA'a design criteria was based on making the algorithm [DES] resistant to differential cryptanalysis..." _AC_ first edition Schneier page 238

    If you want to bust the NSA's chops complain that they made the key length go from 128 to (effectively) 56 bits. Now that hurt...

    =tkk

    --
    Bill Gates - Creationist?!?