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Gain assisted superluminality

  1. Aug 3, 2004 #1
    What would the suggested effect from the results of this experiment on the predictions for the end of the universe, especially if it was a 'cold death'. The people doing the experiment mentioned that the state of cesium used existed at a near absolute zero temperature. In an older universe, wouldn't the temp be closer to that one and wouldn't there also be a lot more cesium in the future than currently exists? What would this mean that in the future transmission of light ( and other forms of energy) would be much faster than now? :uhh:
  2. jcsd
  3. Aug 3, 2004 #2


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    I believe you're talking about the experiments where signals were passed faster than light through a medium exhibiting anomalous dispersion.

    The critical thing about this experiment is that while the phase velocity of the signal was faster than light, the group velocity was not. It did not violate special relativity. You cannot, in fact, transmit information faster than light.

    - Warren
  4. Aug 4, 2004 #3
    I dont think I was clear enough. I wasn't thinking about transmitting info. I was just thinking that towards the end of the universe, materials exhibiting anomalous dispersion would be passing around light peaks (phase velocity?) at speeds faster than light thru a vacuum, and i was trying to find something wrong w/ the idea besides significant absorbtion and perhaps the lack of free energy in the universe at that time. I was looking for the implications; if there are any.
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