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F theory & M theory

  1. Apr 22, 2003 #1


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    what is the relation between the two theories (if there is a connection between them)?

    thaks in advance.
  2. jcsd
  3. Apr 22, 2003 #2
    I haven't even heared of the F-Theory. Do you know anything about it?
  4. Apr 22, 2003 #3
    I haven't heard of F-theory either. I know some of M-theory, but perhaps someone should fill us in on what F-theory is.
  5. Apr 22, 2003 #4


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    F is for "father". It seems to be a 12D string theory that has 2 time dimensions. I'll see if I have any links.
  6. Apr 22, 2003 #5
    2 time dimensions?!! That just isn't logical. If everything takes place at a certain point in time, then every spacial point corresponds to a point in time. Does this reasoning allow for another time dimension?
  7. Apr 22, 2003 #6
    That Net Advance of Physics from the "Physics Napster" topic links to this: abstract. Have fun wading through that.
  8. Apr 23, 2003 #7
    Does anyone have any information on why a theory would even want to incorporate two dimensions of time?
  9. Apr 23, 2003 #8
    So, 2 time demensions would mean two directions of entropy! how cool is that?? Any way, Mentat, I was wondering the same thing.
  10. Apr 23, 2003 #9
    An idea:
    Could two time demensions allow for the future and the past to exist at the same time? Then, time travel to the past could make sense without breaking the first law of thermodynamics. If someone went to the past, the energy/mass of the universe will remain the same, because the person who went to the past would exist in the future. Since both the future and the past exist, energy/mass is not being lost.
  11. Apr 24, 2003 #10
    It couldn't allow for our future and our past to exist at the same time.

    There is some appeal that I can gather from the idea of there being two time dimensions: If there are two time dimensions, then "Pretzeled Time" is possible.
  12. Apr 24, 2003 #11
    You mean, "how impossible is that?", don't you? Entropy can't go in more than one direction, it isn't logical (or at least doesn't seem to be).
  13. Apr 24, 2003 #12
    Okay, back to the drawing board....
  14. Apr 25, 2003 #13
  15. Apr 25, 2003 #14


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    Ok..well..entropy is a NET effect...like on our planet...tons of stuff decreases entropy....but the NET effect on the whole universe is that it goes up...
  16. Apr 25, 2003 #15
    can you be more detailed?
  17. Apr 25, 2003 #16


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    Hm..I dont know the details but Im just providing a general idea....but ok i just realized with 2 time dimensions i have no clue what would be going on...because time as we know it is in one dimension and we cant even imagine what would happen if there were 2 "times"..
  18. Apr 25, 2003 #17
    do you agree that the future might already exist? i think it makes sense, as it solves the paradox involved with time travel to the past.
  19. Apr 28, 2003 #18
    Because entropy is one effect. It cannot both be increasing and decreasing at the same time, can it? This would be self-contradictory/paradoxical.
  20. Apr 28, 2003 #19
    Think of the terms you're using, Majin. You are using the term "future", which is any point in time that has not already come into existence. This means that the future cannot "already exist", by definition.
  21. Apr 28, 2003 #20
    We don't know that the future doesn't exist anymore than we know the past has ceased to exist. We only know what our perceptions tells us and, unfortunately, we only perceive a single slice of time.

    Or as Richard Feynman said:

    It may prove useful in physics to consider events in all of time at once and to imagine that we at each instant are only aware of those that lie behind us.

    Who knows?
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