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Scarcity of antimatter atoms

  1. Aug 25, 2012 #1
    Are there any answers to this question? If equal amounts of matter and antimatter were in existence at the big bang surely each annihilation would remove equal amounts of matter and antimatter?
  2. jcsd
  3. Aug 25, 2012 #2


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    This is one of the big open questions in theoretical physics.

    We know of asymmetries between matter and antimatter, but none of them are large enough to produce the observed baryon asymmetry.
  4. Aug 25, 2012 #3
    I've just read up on mesons. Would they occur naturally and do they interact with matter?
  5. Aug 25, 2012 #4


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    Bear in mind that the asymmetry between matter and antimatter appears to be very small. Today in the universe there are about 10^9 photons for every baryon. So we think (for some reason we don't fully understand, as Nabeshin said) that there was just slightly more matter produced than antimatter, by only 1 part in 10^9. So after it all annihilated, we were left with matter and photons.
  6. Aug 25, 2012 #5
    Thanks for the answer that makes sense of the situation.
  7. Aug 26, 2012 #6
    At least some of the asymmety is due to CP violation. Read up on the BaBar experiment. B and anti-B interactions were observed to lead to stable matter in some cases.
  8. Aug 26, 2012 #7
    Maybe antimatter is just not meant to exist on its own and is just another component of matter. We think of it as antimatter whereas it is really only a subset of matter.
  9. Aug 26, 2012 #8


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    Both matter and antimatter are really just plain "matter". Antimatter does not have exotic properties or anything like that. If the universe were dominated by antimatter instead, we would know that as "matter" and the other as "antimatter".
  10. Aug 26, 2012 #9


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    Yes and yes. Sufficiently high energy radiation can produce mesons. These energy levels are typical of stars and radiation they emit, but can also be due decay of many naturally occurring radioactive isotopes.

    Mesons are matter. But I'm guessing you might mean more conventional matter, like atomic nuclei and electrons. Yes, mesons will interact with these.

    None of the mesons are stable, however. They all have very short life times.
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