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Matter anti matter

  1. Mar 31, 2006 #1


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    Why did matter dominate the universe ? if i read the BB corectly matter and
    anti matter were (produced) in equal amounts.
  2. jcsd
  3. Mar 31, 2006 #2
    One reason (though not the full story if I remember my lectures correctly) is that there is something known as CP violation in the Weak interaction. There is an inherent bias in the Weak interaction which favours certain types of decay. Some theories talk about 'WIMPs' (Weaking Interacting Massive Particles) being very common in the early time of the universe and given their mechanism of decay being the Weak interaction they output slightly more of one type of matter than another, being what we now call 'matter'.

    It's not enough to match up with some observations of the universe though if I remember correctly and other theories are brought in to try to explain what we see in observations.
  4. Mar 31, 2006 #3


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    This is where i get lost, all things being equal and opposite the BB should have been a net pure energy event, i can not find the explanation for a
    matter dominated universe in the literature, can you point me to some
    papers ?
  5. Apr 1, 2006 #4
    I would say they most likely where, and their all but total self-annihilation powered the inflationary era; which took the form of 2 mass ejections or pulses from the north and south poles of a BB event/body that displayed a high degree of angular momentum. One of the polar pulses contained a small remainder of the surviving matter, which became the observable, visible universe. I would presume the other pulse would have contained an equal amount of anti-matter. I would also assume that although there has been no subsequent pulses, the bb event/body remains in existence between the 2 daugther pulses.

    This model seems to answer a lot more questions than just why isn't the observable, visible universe isn't 1/2 matter and 1/2 anti-matter; such as why the Wmap data seems to indicated a prefered direction.
  6. Apr 3, 2006 #5
    That's the thing, there are cases where things aren't equal, some quantum processes have an asymmetry. I can't really point you to any papers, I'm not one for reading papers unless someone points me to them for a specific thing.
  7. Apr 3, 2006 #6
    Let's imagine that thery are made in equal amounts. They would be converted to photons on contact but there is such things as parallel universe. There might be an anti-matter you. But please if you ever meet him don't shake hands! So means there would be another universe that is mainly anti-matter. It just take matter to be produce slightly more than anti-matter to create a matter universe. Justttt a little more would have a great difference as our universe is that big.
  8. Apr 3, 2006 #7
    Can you put a link for your sources.I have herd about parrel universes but never anything about there being antimatter you one of them.
  9. Apr 3, 2006 #8


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    Let's ask the question from another viewpoint. Quantum theory tells us that the vacuum is teeming with virtual particle/antiparticle pairs - over 120 OOM more than we can detect via the expansive pressure or gravitational equivalence of the pairs. I believe that this is true, and that the expansive pressure and gravitational attraction are everywhere in dynamical balance in our universe. In this light, the overdensity of "real" matter in our universe is more of a minor statistical glitch than "domination".
    Last edited: Apr 3, 2006
  10. Apr 3, 2006 #9
    so do all these virtual particals count as dark matter/energy while virtual
    or as the nomal matter that is 5% of everything
  11. Apr 3, 2006 #10


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    That's an astute question - I'll be banned for promoting a private theory if I answer you honestly, though.
  12. Apr 4, 2006 #11


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    It seems we live in a universe with many coincidental, or best fit parameters
    for our time, Turbo, looking through the arxiv, i came across this.


    Authors: Douglas Scott, Ali Frolop
    Comments: 2 pages

    The now standard vanilla-flavoured LambdaCDM model has gained further confirmation with the release of the 3-year WMAP data combined with several other cosmological data-sets. As the parameters of this standard model become known with increasing precision, more of its bizarre features become apparent. Here we describe some of the strangest of these ostensible coincidences. In particular we appear to live (within 1sigma) at the precise epoch when the age of the Universe multiplied by the Hubble parameter H_0 t_0 = 1.

    i guess it is the chicken or egg thing, but one has to wonder at how fortunate we are to even
    be here to ask questions.
    Last edited: Apr 4, 2006
  13. Apr 4, 2006 #12


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    Here is a bit about CP and the "matter-antimatter triangle".

  14. Apr 9, 2006 #13
  15. Apr 13, 2006 #14


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  16. Apr 13, 2006 #15
    is anti-matter stable? without matter to interact with of course
    how long has anyone keap anti-matter in a mag bottle ect
    does it have a 1/2 life like a free neutron?
  17. Apr 14, 2006 #16


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    From Zappers Link

    The experiment found that the transition rate is three trillion (3 x 1012) times per second, measured to a precision of 2%. This is the most precise measurement of this rate ever made and agrees very well with predictions in the Standard Model. A separate analysis by the D0 collaboration at Fermilab was only able to give a range for the transition rate of between 2.7 and 3.3 trillion times per second.

    Can any thing ever get more precise ? :bugeye:
  18. Apr 14, 2006 #17


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    Absolutely! The experimentally obtained value of the "fine structure constant" (usually denoted with alpha) is
    7.297 352 568(24) x 10^(-3)

    where the "(24)" is the error in the last two digits; i.e., instead of an error of 2%, the error here is 0.00000033%.
  19. Apr 14, 2006 #18
    Apparently the new CP violation data is adding to the mystery of the matter-anti-matter imbalance of the visible universe, not solving the problem.

    If someone were to give me decent odds, I would still bet on an anti-matter sister universe.
  20. Apr 15, 2006 #19


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    In astronomy, pulsar J0437-4715 has a period measurement of:

    P = 5.757451831071979(8) ms,

    giving a precision of 0.000000000000014%. I think we got this one to an order of magnitude. :biggrin:
  21. Apr 15, 2006 #20


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    That is astounding :bugeye: but you must be at equiptment limits ?
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