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Plausible FTL communicator

  1. Mar 4, 2016 #1

    wolram

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    What is the most plausible FTL communicator, could we in some way use Tachyons?
     
  2. jcsd
  3. Mar 4, 2016 #2

    mfb

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    Probably a matter of taste.
    Alcubierre drive? At least it does not directly violate general relativity.

    Note that every plausible FTL communication also allows time travel.
     
  4. Mar 4, 2016 #3

    wolram

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    I like it especially if it uses the casimir effect:biggrin:
     
  5. Mar 5, 2016 #4
    Tachyons are only hypothetical mathematical things that can only travel faster than light, I'm pretty sure nobody thinks they actually exist any more then, say, a negative number of apples can physically exist.
    If for SF purposes though, we just suppose that they do exist and we can produce them, there is then another problem.
    How does one go about encoding information into FTL particles using technology that is itself limited by the speed of light?
     
  6. Mar 6, 2016 #5
    Alcubbiere drive as a communicator? Sort of like a beefed up carrier pigeon, you put the mail bags in it and send it on its way?
    Isn't this the drive that needed energy equivalent to the mass of Jupiter, then physicist Harold White brought it down to only 700 kg or less? Now the Wikipedia article on Alcubbiere has info on a paper by S. Krasnikov that says it might only take a few milligrams of exotic matter, paper on APS http://journals.aps.org/prd/abstract/10.1103/PhysRevD.67.104013 and paper on arxiv http://arxiv.org/abs/gr-qc/0207057
     
  7. Mar 6, 2016 #6
    I've been thinking hard about this... my interests are far beyond the spacetime dynamics, so even if there is say a "classical 'c' time delay, there still can be a "message" encoded in frequency modulation in gravitational waves. In line with your query, as well as the Star Trek type ideology, I wonder if you couldn't "warp" a magnetic field, in such a way to create gravitational waves, that would oscillate particles so that you could "receive" a message in the modulation of the resultant frequencies observed in the particles. I'm not familiar enough with the theoretical Alcubbiere warp physics, but common sense tells me if you can move mass through space, moving oscillations through mass through space to transfer information to distant objects should be trivial.
     
  8. Mar 6, 2016 #7
    Now this info I remember is like 20 years old... so.... Wasn't there a type of seastar that would show spooky action at a distance like if researchers would move the leg of one seastar then the other seastar would also move the same leg kms away?
     
  9. Mar 6, 2016 #8
    I've never heard of anything like that.
    Without some kind of credible reference link concerning this phenomenum speculation is pointless
     
  10. Mar 6, 2016 #9
    I was something about 2 guys each had a starfish and they were experimenting with them and one day one of the guys had a stroke and he was clutching the starfish really hard and the other starfish assumed the same shape and his friend realised something's wrong... Does nobody remember the, must have been on a TV show or something. It's a really long time ago.
     
  11. Mar 6, 2016 #10
    So, what about FTL communicators which interact with Lorenz ether?
     
  12. Mar 7, 2016 #11

    mfb

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    I'm not aware of any plausible theory doing that. There is no point in a Lorenz ether in current theories, so that concept got discarded long ago.
     
  13. Mar 7, 2016 #12
    Could you open up a stable wormhole? It doesn't have to be big, just big enough to pass regular slower than light communication through.
     
  14. Mar 7, 2016 #13

    Ryan_m_b

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    There are a few SF-franchises that use wormholes in an interesting and (whisper it!) realistic way, insofar as them not being considered straight up impossible. To avoid issues of time travel the wormholes have to be physically transported to the points needing to be linked and any attempt to make a roman ring causes the wormholes to instantly collapse. IIRC it was physicist Matt Visser who proposed the latter might be a real consequence of stable wormholes.
     
  15. Mar 8, 2016 #14

    DHF

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    That is extremely interesting. How would FTL communications allow time travel?
     
  16. Mar 8, 2016 #15
    I don't see it either. I'm picturing a simple set-up in local space, suppose a satellite at the Sun opens a wormhole next to the Earth to send a message that a flare is headed towards Earth. It saves the ~8 minute "c" delay for the message to travel, but I don't see any reason to conclude causality would be violated.
     
  17. Mar 8, 2016 #16

    mfb

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    Everything that is FTL in one reference frame is backwards in time in a different reference frame. That is an unavoidable consequence of relativity.
    If you keep the principle that physics is the same in every reference frame, you can go FTL in all reference frames, which allows to go to your own past.
     
  18. Mar 8, 2016 #17
    What´s then more plausible: that a FTL communicators are incidentally a time machine because frames are still equal, or that FTL communicators reveal a preferred frame not detectable by any other means?
     
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