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Questions on reversed Coulomb force.

  1. Oct 5, 2007 #1
    Questions on reversed "Coulomb" force.

    I've seen that with Moeller scattering, the attractive force between
    the nucleus and the electron can become repulsive at high relativistic
    velocities of the electron. What are the energies required for this to
    Is there an analogous result between electrons, i.e., in electron-
    electron scattering, where the repulsive force between them switches
    to become attractive at high energies?
    The strong nuclear force operates as an attractive force even between
    protons at distances of the size of the nucleus, about 10^-15 m. This
    works even for protons beamed towards a nucleus at short distances,
    not necessarily already contained within a common nucleus.
    But shouldn't this distance be frame dependent? If the protons are
    aimed toward a nucleus but to be a longer distance away, shouldn't
    they regard the distance to be Lorentz contracted at sufficiently high
    If the proton beam say was aimed to skirt the outside of an atoms
    electron cloud at about 10^-10 m away from the nucleus, shouldn't a
    Lorentz contraction factor of 10^5 cause the protons to regard the
    distance to be within the 10^-15 distance to the nucleus at which the
    strong force is active?
    The proton has a rest energy of close to 1 GeV. So a Lorentz factor
    of 10^5 would correspond to giving the proton an energy of 100 Tera
    eV. Not even the LHC is expected to get this high. However, Fermilab
    gets up to 1 TeV. If the proton beam was aimed to come within 10^-12 m
    of the nucleus, where the strong force would not be expected to
    operate, then Lorentz contraction should make the distance appear as
    10^-15 m to the protons, where the strong force would operate. Has
    such an effect been seen?

    Bob Clark
  2. jcsd
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