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Experimental Evidence and QFT.

  1. Mar 14, 2006 #1
    After reading one of ZapperZ's posts in the Relativity subforum, I just thought I'd ask the following:

    What predictions of QED, QCD, Electroweak and the Standard Model still aren't confirmed?

    I'd be particularly interested in hearing unconfirmed predictions from QED.
  2. jcsd
  3. Mar 14, 2006 #2


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    For the Standard Model, we haven't found the Higgs particle(s) yet. That's a pretty significant gap, considering that the Higgs mechanism is what gives rise to the masses of all the other fundamental particles, in the SM.
  4. Mar 14, 2006 #3


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    There's something observed that the SM DOESN'T predict - not really, truly- and that's quark confinement. Asymptotic freedom (weakening of the strong force at high momenta and short distances) is predicted and observed, but the other end, infrared slavery, the great strengthening of the strong force at low momenta and large distances so that it becomes unbreakable at some finite distance, has only been sorta demonstrated. Really convincing theory is lacking.
  5. Mar 14, 2006 #4
    It is my understanding that QED of Standard Model does not explain anomalies in orthopositronium annihilation, first discovered in 1987 by physicists at University of Michigan, see these reviews:

    Adkins, et. al Phy. Rev A. 1992. v 45 3333-3335
    Levin, B. M. Physics of Atomic Nuclei 1995. v 58(2) 332-334
    Adkins, et. al. 1999. Phys. Rev. A. v 60(4) 3306-3307
  6. Mar 14, 2006 #5


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    I did my PhD thesis partly on the OPs decay rate problem (in part because it seemed at the time that it could lead to new physics). I calculated higher order corrections that still did not bring theory in line with the experimental result of the Michigan group. Later, shortly after my thesis, a japanese group got a less precise result that differed significantly from the Michigan group and in agreement with theory.
    I haven't kept up with the publications, but discussions with colleagues recently (meaning within a year) revealed that new measurements were in line with theory...the discrepancy had gone away. (I will try to find a reference)

    as far as I know, there are no experimental discrepancy with QED.

  7. Mar 15, 2006 #6
    Thank you. I would very much like to read the references, since I have recently communicated with a physicist who suggested the OP decay rate problem does still exist, and I could forward your reference to him.

    I have a question since you have great knowledge on this topic of OP of which I have interest, but next to no knowledge. Suppose we have OP formed in different isotopes of neon (22-Ne, 21-Ne, 20-Ne). Would you have any reason via theory to expect the three different OPs formed within each isotope to be "different" from each other ? Do you know if such an experiment has been conducted ? It has been suggested that such a difference in OP between these three isotopes "may" exist--just checking to see if this is an active topic of research.
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