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Theoretical Breakthrough For Quantum Cryptography

KentuckyFC writes "Quantum cryptography uses the quantum properties of photons to guarantee perfect secrecy. But one of its lesser known limitations is that it only works if Alice and Bob are perfectly aligned so that they can carry out well-defined polarization measurements on the photons as they arrive. Physicists say that Alice and Bob must share the same reference frame. That's OK if Alice and Bob are in their own ground-based labs, but it's a problem in many other applications, such as ground-to-satellite communications or even in chip-to-chip communications, because it's hard to keep chips still over distances of the order of the wavelength of light. Now a group of UK physicists have developed a way of doing quantum cryptography without sharing a reference frame. The trick is to use entangled triplets of photons, so-called qutrits, rather than entangled pairs. This solves the problem by embedding it in an extra abstract dimension, which is independent of space. So, as long as both Alice and Bob know the way in which all these abstract dimensions are related, the third provides a reference against which measurements of the other two can be made. That allows Alice and Bob to make any measurements they need without having to agree ahead of time on a frame of reference. That could be an important advance enabling the widespread use of quantum cryptography."

15 of 116 comments (clear)

  1. Stay away from this by Anonymous Coward · · Score: 5, Funny

    One thing, with quantum crypto, the code changes when you look at it. In other words, you have to know the key before seeing it.

    Two, it kills a LOT of cats! You get the code right, and BAM! dead cat.

    PETA will be against this!

    1. Re:Stay away from this by Anonymous Coward · · Score: 1, Funny

      Mmmm, sheep

    2. Re:Stay away from this by nstlgc · · Score: 3, Funny

      Yeah, that's just what I was going to say. He stole my idea!
      Don't panic. Find comfort in the fact that there's a universe in which a bear brutally sodomized then killed him before he was able to push the Submit button.

      --
      I'm Rocco. I'm the +5 Funny man.
  2. Re:qutrits? by ArsonSmith · · Score: 2, Funny

    cute tits or quit its?

    --
    Paying taxes to buy civilization is like paying a hooker to buy love.
  3. You lost me at hello... by PPalmgren · · Score: 4, Funny

    Boy am I glad I didn't pursue that physics major. The only thing I got out of that is that Alice and Bob needed a marriage counselor to reconcile their differences.

    Anyone mind converting that attempt in layman's terms to something useful, like a car analogy?

    1. Re:You lost me at hello... by JaneTheIgnorantSlut · · Score: 4, Funny

      Do Carol and Ted know about this?

  4. Re:qutrits? by Anonymous Coward · · Score: 1, Funny

    Applying the standard naming conventions would result in qutits. I much prefer qutits.

    And the scientific community would be rather better off choosing names that let us focus on the furtherance of humanity's knowledge of the inner workings of the universe than opening the door for juvenile jokes.

    The planet Uranus thanks you.

    Everyone else thinks you're a bit too uptight.

  5. Translation of summary by genghisjahn · · Score: 3, Funny

    Glap glar photons biddle doo-vack triple photon vajmu double photon zirreyzoo-zah picture frame powlat pweegoo paparazzi photos of Alice and Bob.

    --
    Sorry about the mess.
  6. Re:"This solves the problem by embedding it...." by Culture20 · · Score: 1, Funny

    Gentlemen, we have reached magic. Scientists are now no different than necromancers.

  7. Just wondering .. by fractalspace · · Score: 3, Funny

    Why cant they simply open a sub space channel and use a Tachyon pulse to synchronize the two frames ?

    1. Re:Just wondering .. by ElAurian · · Score: 4, Funny

      They'd have to reroute the plasma flow and depolarise the graviton matrix first. Duh.

  8. Masters of the world by NCamero · · Score: 2, Funny

    I, for one welcome our new quantum overlords.

  9. Re:Quantum Communications by Arthur+Grumbine · · Score: 2, Funny

    (It would arouse me if replies to this post started simply "Wrong.")

    Not to judge your lifestyle choices, but I'm pretty sure that the reason no one has replied as such has to do with the collective will of the community not to see you aroused.

    --
    Now that I think about it, I'm pretty sure everything I just said is completely wrong.
  10. Re:"This solves the problem by embedding it...." by K.+S.+Kyosuke · · Score: 4, Funny

    Has it occurred to anyone else how UNBELIEVABLY FRIGGIN' COOL it is that a line like that shows up in an article that is talking about building an actual, physical device?

    I can vividly see the label on the unit packaging: "Dimensions: 0.45 x 0.3 x 0.25 x 1.7 m"

    --
    Ezekiel 23:20
  11. Kids today... by grepya · · Score: 2, Funny

    ... if Alice and Bob are perfectly aligned so that they can carry out well-defined polarization measurements ....

    Oh... so that's what the kids are calling it these days... ??