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Wormholes-Photons Arriving Before Being Sent

  1. Dec 27, 2004 #1
    Wormholes--Photons Arriving Before Being Sent

    I was just watching a show on String Theory on PBS and recalled an interesting experiment a few years back. I can't find anything about the experiment, so maybe someone can point me to a source where I can read more about it (or give me names of those who worked on experiment so I can search for it).

    A few years ago, some physicists were shooting photons through a block of lead and discovered that, of the few photons that made it through the other side of the block, some of them had exited the block of lead before they were shot into the front of the block of lead. That is, some of the photons arrived before they had ever left!

    Does anyone know what I'm talking about? I'd like to read more about this because it was theorizied that these photons may have found a wormhole that enabled them to exit the block before they had ever entered it.

    Thanks for your help.
  2. jcsd
  3. Jan 18, 2005 #2
    I can't believe that there isn't anyone around here who isn't familiar with this experiment.

    Scientists shot photons through a block of lead. Some of the photons exited the block of lead before they were shot into the lead thus leading some to believe that this was the work of wormholes.

    I am looking for some more information on this such as the University doing the experiment, name of the scientists, etc. so I can google it and find more info.

    Can't anyone help? Come on, I would have figured that this would have been huge talk with you Physics folks.
  4. Jan 18, 2005 #3
    I recall the media stir about it but nothing else sorry.
  5. Feb 4, 2005 #4
    Well, at least one person out there knows what I'm talking about :D.

    Perhaps more?

    As far as physics goes, if those photons were arriving at their destination before being sent, I would have thought that to be one of the most significant discoveries in the history of mankind.

    Yet, no one around here has heard of this, save for one.
  6. Mar 3, 2005 #5

    Hey StringDude,

    I haven't seen the show you are talking about. But this paper [1] might be relevant. It is purely theoretical work (no experiments) examining how GR might deal with situations in which an object (eg, a billiard ball) is allowed to go through a wormhole, travel "backwards in time," and effectively get set on a collision course with the earlier version of itself. I can tell you more if you are interested.

    You can also read about this stuff in Thorne's pop-sci book, Black Holes and Time Warps.


    [1] Echeverria F., Klinkhammer G., and Thorne K.S. Billiard balls in wormhole spacetimes with closed timelike curves: Classical Theory. Phys. Rev. D 44 (4), p 1077, 15 Aug 1991 http://prola.aps.org/abstract/PRD/v44/p1077_1
  7. Mar 4, 2005 #6
    Hello stringdude,

    this article http://physicsweb.org/articles/world/13/9/3 is not about wormholes, but it deals with "The observation of a light pulse leaving a gas-filled chamber before it had even arrived"


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