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      CommentAuthorNygaard
    • CommentTimeJan 16th 2011
     (9426.1)
    So, apparently, you can now take pictures with entangled photons; that is, light that has never actually reflected off or even been near the object being photographed.

    Since I am among the unculured swinish masses who do not comprehend things with quantum in them, I trust someone can explain the awesomeness of this to me. Because I understand just enough to catch the whiff of awesome, but none of the specifics.
  1.  (9426.2)
    The implications might become clearer in conjunction with this article. More and more physicists acknowledge Shih's views on the nature of light due to his experimental work that shows light emitted from "classical" sources (such as the sun) possesses the same quantum properties like light emitted from "nonclassical" sources (e.g. lasers). This would allow ghost imaging, said photographing with entangled photons possible since the early noughties, utilizing classical light sources to have the same resolution as techniques utilizing nonclassical ones, so satellites looking behind a cloud cover might become a reality in the near future.

    Disclaimer: I'm just a member of the superstitious riffraff, so one of those physicists might find a formal error in the above description of their magicks.
    • CommentAuthorFan
    • CommentTimeJan 16th 2011
     (9426.3)
    In my physics class at school about 35 years ago, we had a lesson about the 'wave' nature of light.

    Imagine a line of sea waves, hitting a breakwater. Imagine that the breakwater has a hole/slit in it: waves on the other side of the breakwater will radiate out from the slit.

    Imagine that the breakwater has two slits in it: waves will radiate out from both slits, and interfere with (sometimes add, sometimes subtract) each other.

    Take a piece of opaque glass, put two transparent slits in it side by side, put some unexposed photographic flim behind it: the light will expose a series of several bands on the film, being the interference pattern of the light coming through both slits (and showing that light sometimes behaves like a wave).

    Repeat the experiment, with the light intensity so low that it's shining no more than one photon (one particle of light) at a time. You'll still see the interference pattern. DUN DUN DUH! Each photon is going though either/both slits, and is probabilistically (i.e. in a quantum way) interfering with itself.
    •  
      CommentAuthorNygaard
    • CommentTimeJan 20th 2011
     (9426.4)
    Thanks! The article seems to sum it up. Coolest part: "'It is clear that the experimental set-up can be directly applied to sensing applications,' Shih told New Scientist."

    Also, the comment section is intriguing; people trying to work it out in their heads, guessing at error sources, and voicing science fiction-inspired hopes. Seeing back in time, a suggestion for getting more than an outline image, and a long string of incomprehensible sciency babble from someone in Firenze. Reminded of Gibson's Gernsback Continuum - pop culture and amateur culture always making little riffs on new science whenever they touch. I assume they must be deeply affecting each other. I'd spend some time wondering how much, but I have to set my Star Trek-style personal communicator to wake me up for work tomorrow. :)