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Challenges of very high energy physics

  1. Mar 26, 2012 #1

    I'm not very "hip" with how accurate current experimental techniques are at distance scales less then that of the proton's size, but I am wondering about how strong our current theoretical tools are (and assumed to be) at smaller scales. I know we are searching for a quantum theory of gravity that is assumed to come into play at distance scales [itex]\approx 10^{-34}\text{m}[/itex], but looking at that number, it is outrageously small.

    So small, that it seems to me there is as much "space" between the size of a proton and that length scale, as there is between our solar system and the proton size. Clearly physics as we know it changes dramatically between solar system dynamics, and atomic physics, are we possibly jumping the gun looking for unified theories etc... when we have so much "distance" still to cover? Another example, LQG displays that it can remain UV-finite even while coupling to a fermion field, yet, is there reason to believe that the fermion field physics remains the same in a domain nineteen orders of magnitude smaller then where it is found successful?

    Thanks in advance,
  2. jcsd
  3. Mar 26, 2012 #2


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    Science Advisor

    We haven't reached energy scales where we can verify all aspects of standard model yet. So no, we are nowhere near probing nature at these scales, and I'm not sure we ever will be. But unified theory isn't guaranteed to give predictions that are verifiable only at these length/energy scales. There could be predictions we can actually test. Going back, again, to the fact that there are currently enough holes in experimental support for standard model. Whether any are there due to problems with model is impossible to tell, of course, because a lot of them are due to either experimental or numerical limitations.
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