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Sending messages into the past

  1. Dec 16, 2012 #1
    Not sure where to post this, but here goes:

    I'm not that knowledgeable about tachyons (particles that always go faster than the speed of light, if they exist), but is it true that they go backwards in time according to theory?

    If that is true, and if scientists find them, would scientists be able to send messages backwards in time?

    If that is true, would our philosophy concerning causality require an immense shift in thinking (effect preceding cause, etc..) ?

    Just saying, would the existence of tachyons lead to time paradoxes or other strange effects?
    Last edited: Dec 17, 2012
  2. jcsd
  3. Dec 17, 2012 #2


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  4. Dec 17, 2012 #3
    Hey thanks for the links. They are helpful. So basically, if Alice sent a message to Bob going faster than the speed of light, Bob might return a message back before Alice's initial message. Thus, that violates causality and makes faster-than-light communication impossible.

    I guess I was looking for something more exotic, but I guess that was all in my head.
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