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String Theory's inconsistency with Relativity

  1. Mar 22, 2015 #1
    Are the general principles of string theory “the properties of fundamental particles are due to their unique vibrational pattern of strings in 10 or 11 or 26 dimensions” incompatible with both general and special relativity? due to an observer would be able to detect changes in properties of fundamental particles e.g. electron charge, because of the perceived change to the observer of the time dependent vibrational pattern if the particle was traveling relative to the observer or experiencing a different level of gravitational potential ? Although the properties of the particle within its own reference frame would remain constant.
     
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  3. Mar 23, 2015 #2

    Orodruin

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    No, string theory is particularly constructed to be the theory beneath general relativity.
     
  4. Mar 23, 2015 #3
    Can you give any more details ? The only way i understand to maintain the observable properties would be through quantum time dilation proportional to the base vibrational frequency? and i didn't think string theory was that far advanced.
     
  5. Mar 23, 2015 #4

    Orodruin

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    It is unclear what you believe would violate relativity. Do you also think electrons in quantum field theory violate relativity because their energy is frame dependent?

    Just like QFT, string theory is constructed in an explicitly relativistically invariant framework.
     
  6. Mar 24, 2015 #5

    stevendaryl

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    This is way beyond my understanding, but I thought I would just mention it, in the hopes that someone else can supply the details: There is some sense in which string theory is nonlocal, but in a benign way (the nonlocality does not imply causality violations at a macroscopic scale, although it might at a microscopic scale):

    http://arxiv.org/pdf/1310.4957v2.pdf
     
  7. Mar 24, 2015 #6

    PAllen

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    Also, just search for 'string' in the full text of:

    http://relativity.livingreviews.org/Articles/lrr-2014-4/ [Broken]

    to see many proposed ways string theory might lead to deviations from GR (and I don't mean at the Planck scale, or for BHs).

    However, there are no SR violations expected (so far as I've heard).
     
    Last edited by a moderator: May 7, 2017
  8. Mar 28, 2015 #7
    Thanks for the links. I still don't know it describes what I’m looking for; there was a lot that I am still struggling to understand. I will give a more specific example of the conflict with relativity, feel free to point out any errors in my reasoning or assumptions.

    Consider a particle creation event of an electron-positron pair; the general principles of string theory state that the properties of these two particles are attributed to their unique vibrational pattern.

    I like to consider them 180 degrees out of phase but equal and opposite in all aspects of their mode of vibration, hence matter antimatter annihilation would just be total destructive interference of all vibrational modes.

    If you consider each of these particles to be the equivalent of individual clocks, similar to the light clock example commonly used in relativity examples, as they are they are matter undergoing repetitive motion. Then if you take one of the particles and make it experience relativistic time dilation (ether special or general), this particle will vibrate (clock tick) slower compared to its pair. Then at some level of relativistic time dilation you would be able slow the vibration of on particle enough so that when you brought the particles back together their vibration modes are now in phase with one another. Effectively changing the characteristic of the fundamental particle under the definition of string theory i.e. positive to negative charge through the 180 degree phase change of its vibrational mode.

    This is my understanding of how string theory particle characteristics and relativity would combine. Is there some mechanic that can maintain the opposite vibrational modes in string theory?

    I think that the characteristic properties of particles will likely be preserved due to a theory of quantum gravity that will include quantum time dilation, I have not found much on the topic.
     
  9. Mar 28, 2015 #8

    PeterDonis

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    No, that won't work, because when particles and antiparticles annihilate, other particles come out. For example, when an electron and a positron annihilate, two photons come out. From a string theory perspective, this means the "vibrational modes" can't disappear; they can only change from one set of modes (the electron/positron modes) to another (the photon modes).

    Do you have a reference for this?
     
  10. Mar 31, 2015 #9
    "total destructive interference" was an perhaps an exaggeration, i acknowledge that the total mass energy is conserved. When you say they "vibrational mode" can't disappear; they can only change form, is the mechanic of this transformation known? i think in some ways it is equivalent to the same thing, where i was thinking of destructive interference where the mass of the matter antimatter is converter in to radiation i.e the photons. You describe it changing form into the photons, energy can be conserve in both views the only difference is if the original "strings" survives or new string are created.

    No i don't have a reference, hence the "this is my understanding". I only ask because the principles of the two theories seem to be in conflict and i can not reconcile how the two particles described would not change phase under relativistic time dilation.
     
  11. Apr 1, 2015 #10

    Orodruin

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    Why would you think that this change of phase violates relativity? Even in relativistic quantum mechanics, the frequency associated to a particle is proportional to its energy and thus not a Lorentz scalar, energy is different in different frames - this is even true in Newtonian mechanics.
     
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