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Testing Einstein's 'Spooky Action at a Distance'

smooth wombat writes "Travelling to a time in the past is, as far as we know, not possible. However, Einstein postulated a faster-than-light effect known as 'spooky action at a distance'. The problem is, how do you test for such an effect? That test may now be here. If all goes well, hopefully by September 15th, John Cramer will have experimented with a beam of laser light which has been split in two to test Einstein's idea. While he is only testing the quantum entanglement portion, changing one light beam and having the same change made in the other beam, his experiment might show that a change made in one beam shows up in the other beam before he actually makes the change."

8 of 375 comments (clear)

  1. Very neat and interesting! by Kagura · · Score: 5, Informative

    But we've already done it: Elitzur-Vaidman bomb-testing problem

    At the bottom, it says that the equivalent experiment has already been performed, and TFA sounds like it is nearly the same experiment.

  2. A True Hacker by phantomfive · · Score: 5, Informative

    John Cramer, the designer of the experiment, is really quite a colorful guy. He last got the attention of the press by simulating the sound of the big bang using Mathematica. Useless research of course, but who wouldn't laugh hearing that the big bang sounded like "large jet plane 100 feet off the ground flying over your house in the middle of the night?" At heart this guy is a physics hacker (in the true sense of the word hacker).

    He also writes science fiction, so you can tell he completely enjoys science. Betcha anything he's doing this experiment, not because he thinks it will work, but just 'cause he wants to see what will happen. I can totally agree with that. It's the right reason to do research.
    --
    Looking for a C/C++ job in Silicon Valley?

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    Qxe4
    1. Re:A True Hacker by xPsi · · Score: 4, Informative

      I worked with John on the STAR experiment at RHIC in the pion interferometry group. Your description of him as a physics hacker (in a good way) is right on. I do sometimes wonder about his sanity when I read about his latest projects (e.g. see TFA) -- but he is by no means a crank or crackpot. Oddly enough, he also does dog shows as an owner. His personality would fit right into Christopher Guest's movie Best in Show (I also mean that in a good way). So think of him as a dog trainer/quantum mechanic/science fiction author. He's basically a nerd renaissance man.

      --
      i\hbar\dot{\psi}=\hat{H}\psi
  3. Re:Been there, Done that by MOBE2001 · · Score: 4, Informative

    Didn't the Aspect Experiment back in the '80s demonstrate this effect?

    Of course. Slashdot is getting weird by the day. First off, it was not Einstein's idea. Eisntein was against it and this was made famous in a paper he wrote with two other physicists who agreed with him. It's called the Einstein-Podolsky-Rosen paradox or EPR paradox for short.

  4. Quit it by missing000 · · Score: 5, Informative

    Einstein formulated the theory with 2 colleagues, Podolsky and Rosen.

    It's called the EPR Paradox in the scientific community.

    Einstein was no fan of it, and he believed it was a way to point out how silly the idea of Quantum Mechanics was, but he was very much the discoverer of it.

    This is as important to understanding Einstein as "God does not play at dice", his basic objection to the probability implications of QM and EPR.

    1. Re:Quit it by thelexx · · Score: 3, Informative

      I love how people grab on to that one phrase of his and make out like he was Mr Pious or something:

      "It was, of course, a lie what you read about my religious convictions, a lie which is being systematically repeated. I do not believe in a personal God and I have never denied this but have expressed it clearly. If something is in me which can be called religious then it is the unbounded admiration for the structure of the world so far as our science can reveal it."

      Albert Einstein, in a letter March 24, 1954; from Albert Einstein the Human Side, Helen Dukas and Banesh Hoffman, eds., Princeton, New Jersey: Princeton University Press, 1981, p. 43.

      --
      "Gold still represents the ultimate form of payment in the world." - Alan Greenspan, 1999
  5. Re:Been there, Done that by msevior · · Score: 5, Informative

    Actually no. This new experiment is VERY interesting. The new experiment proposed by John G. Cramer aims to test an idea that might allow quantum signaling.

    See this:

    http://www.analogsf.com/0612/altview.shtml

    The idea is to see if an interference pattern will spontaneously change from a single slit to a double slit merely by moving the position of where entangled photons are destroyed.

    I think there is a reasonable chance this will work. This is interesting as it in principle allows FTL communication.

    After that his ideas get REALLY interesting.....

  6. Re:"Faster than light"... by mrpeebles · · Score: 3, Informative

    A big criticism of quantum mechanics (still) is that nobody is exactly sure the minimum you have to do to one entangled particle to "measure" it, which determines what the person with the other entangled particle will he when he "measures" his particle. Schrodinger's cat paradox has never beeon completely satisfactorily answered. The existance of quantum entanglement is well established, though.

    Nobody has ever found a way to use entangled particles to send FTL messages. In principle it is impossible. I have never even heard anybody else but this guy musing about ways it might be possible.