Matter anti matter

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wolram
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Main Question or Discussion Point

Why did matter dominate the universe ? if i read the BB corectly matter and
anti matter were (produced) in equal amounts.
 

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  • #2
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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.
 
  • #3
wolram
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AlphaNumeric said:
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.
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 ?
 
  • #4
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wolram said:
Why did matter dominate the universe ? if i read the BB corectly matter and
anti matter were (produced) in equal amounts.
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.
aguy2
 
  • #5
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wolram said:
This is where i get lost, all things being equal and opposite the BB should have been a net pure energy event
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.
 
  • #6
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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.
 
  • #7
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whiteholes said:
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.
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.
 
  • #8
turbo
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wolram said:
Why did matter dominate the universe ? if i read the BB corectly matter and anti matter were (produced) in equal amounts.
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".
 
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  • #9
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turbo-1 said:
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".
so do all these virtual particals count as dark matter/energy while virtual
or as the nomal matter that is 5% of everything
 
  • #10
turbo
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ray b said:
so do all these virtual particals count as dark matter/energy while virtual
or as the nomal matter that is 5% of everything
That's an astute question - I'll be banned for promoting a private theory if I answer you honestly, though.
 
  • #11
wolram
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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.

http://arxiv.org/abs/astro-ph/0604011

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.
 
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  • #12
Labguy
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Here is a bit about CP and the "matter-antimatter triangle".

http://www.fnal.gov/pub/inquiring/questions/cp_violations.html
http://www.fnal.gov/pub/ferminews/Ferminews00-08-25.pdf
http://www.umich.edu/~gs265/bigbang.htm
As it began to cool, at around 10^-43 seconds after creation, there existed an almost equal yet asymmetrical amount of matter and antimatter. As these two materials are created together, they collide and destroy one another creating pure energy. Fortunately for us, there was an asymmetry in favor of matter. As a direct result of an excess of about one part per billion, the universe was able to mature in a way favorable for matter to persist. As the universe first began to expand, this discrepancy grew larger. The particles which began to dominate were those of matter. They were created and they decayed without the accompaniment of an equal creation or decay of an antiparticle.
 
  • #15
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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?
 
  • #16
wolram
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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:
 
  • #17
ahrkron
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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%.
 
  • #18
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ZapperZ said:
New results from CDF producing even more convincing CP violation.

http://physicsweb.org/articles/news/10/4/6/1

Zz.
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.
aguy2
 
  • #19
SpaceTiger
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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:
 
  • #20
wolram
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SpaceTiger said:
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:
That is astounding :bugeye: but you must be at equiptment limits ?
 
  • #21
wolram
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aguy2 said:
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.
aguy2
Can you enlarge, aguy2 ?
 
  • #22
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wolram said:
Can you enlarge, aguy2 ?
I have been contending that the visible universe seems to be acting more like an anitropic 'pulse/jet', than an isotropic expansion. If this is the case, it would probably mean that the pre-inflationary BB event/body had displayed a high degree of angular momentum, which is entirely within reason. Of course if the all-matter visible universe was the consequence of a massive polar pulse emitted from the BB event/body, it would seem highly likely that an anti-matter "sister" universe would have been ejected from the other pole of the BB event/body.
aguy2
 

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