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Why is the Universe electrically neutral?

  1. Jul 5, 2012 #1
    That's a conundrum that I've seen posed -- certain people have claimed that it's very improbable.

    But here is what I think is a plausible solution. If the Universe originated from a quantum fluctuation or something similar, it would have to have originated as a gauge singlet. Being a gauge singlet means having zero electric charge, thus implying that the Universe is electrically neutral.
  2. jcsd
  3. Jul 6, 2012 #2

    Simon Bridge

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    Which changes to the question of why it has to be a gauge singlet of course. Discovery that the Universe is not electrically neutral would mean that the gauge-singlet idea of the creation of matter is wrong and we'd have to come up with something else. So - is this a strong argument?

    "Certain people" would be the "Electric Universe" and "Plasma Cosmology" crowd?

    Some discussions into why it is likely that the Universe is electrically neutral:

    The question of how it came to be that the Universe is charge-neutral on the large scale is quite deep ... a simple look:
    ... gives some of the idea.
  4. Jul 6, 2012 #3
    In post #39 that thread, xantox proposed that the Universe is electrically neutral (total charge = 0) because of gauge symmetry.

    I think that that's another version of the gauge-singlet idea.

    That's because one can always find a gauge-symmetry operator that can transform one member into another of an irreducible-representation gauge multiplet. Only for a singlet is there only one member to choose from.
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