A Question For Physicists About The Prevalance of Matter Over Antimatt

[David Sklansky]

Its a million to one shot that I came up with a new idea about this subject but I'll bring it up anyway.

Physicists are puzzled by the fact that the universe seems to contain much more matter than anti matter. They realize that this state of affairs would occur even if matter started oof with only a tiny edge. Because when they meet they annhilate each other. But they know of no good reason why matter should have started out with an edge.

My question is: Isn't how things start out also a matter of randomness? Like all that other particle stuff. If so that explains things simply enough.

[pvn]

[ QUOTE ]
Its a million to one shot that I came up with a new idea about this subject but I'll bring it up anyway.

Physicists are puzzled by the fact that the universe seems to contain much more matter than anti matter. They realize that this state of affairs would occur even if matter started oof with only a tiny edge. Because when they meet they annhilate each other. But they know of no good reason why matter should have started out with an edge.

My question is: Isn't how things start out also a matter of randomness? Like all that other particle stuff. If so that explains things simply enough.

[/ QUOTE ]

Sounds reasonable to me. If every bit of stuff created at the big bang (or whatever) is a coinflip for being matter or antimatter, then it would be really, really unlikely for it to be an exact 50/50 split, with the likelyhood dropping as the number of "stuff pieces" created increases, right?

However, I thought I remembered reading something somewhere that someone had figured out that it's not a 50/50 shot, that matter will be more frequent than antimatter due to something or other (vague, I know, it was a while back and I don't know much about this beyond the "brief history of time" level). I could be way off here, obviously.

Bonus points if you can bamboozle people with the fact that matter will always win over antimatter (without them figuring out that the reason for this is that we'll always call the winner matter and the loser antimatter).

[goofball]

Well, physicists really know very little about how the universe began

[pvn]

[ QUOTE ]
Well, physicists really know very little about how the universe began

[/ QUOTE ]

I like people who don't know [censored] about something but just make a bunch of guessess and pretend they're experts. Like AP voters doing preseason college football polls. Shows some real stones.

[m_the0ry]

There are some good hypotheses about why the matter antimatter asymmetry exists. This page explains a few of them. There's quite a large field of physics studying 'CP invariance' which is (brutally oversimplified) the assumption that antimatter can mimic matter and - in practice - there is no way to even tell the difference between the two when we make certain mirror image transformations (time reversal, etc).


As for my personal (and generally unfounded) belief, unless there is an unexpected breakthrough in some of these experiments, the antimatter / matter problem is really easy to explain away with the 'finely tuned universe' idea. It is somewhat maligned and cannot be considered a theory because it makes no predictions, but the philosophical foundation is fairly sound. Essentially, universes are formed and naturally selected in a darwinian process - those without antimatter/matter imbalance simply annihilate all matter and never allow the complexities of life/etc which could ever allow us to ask the question to begin with. This assumes you have a sort of multiverse-like view on how universes are created and how many of them there are.

[Metric]

http://en.wikipedia.org/wiki/Antimatter

[ QUOTE ]
It is now thought that symmetry was broken in the early universe during a period of baryogenesis, when matter-antimatter symmetry was violated. Standard Big Bang cosmology tells us that the universe initially contained equal amounts of matter and antimatter: however particles and antiparticles evolved slightly differently. It was found that a particular heavy unstable particle, which is its own antiparticle, decays slightly more often to positrons (e+) than to electrons (e-). How this accounts for the preponderance of matter over antimatter has not been completely explained. The Standard Model of particle physics does have a way of accommodating a difference between the evolution of matter and antimatter, but it falls short of explaining the net excess of matter in the universe by about 10 orders of magnitude.

[/ QUOTE ]

[PLOlover]

do we know there aren't antimatter galaxies?
what about dark matter? seems like we can't account for most of the mass out there anyway.

[Jamougha]

PLO,

if there were significant areas of antimatter then we would notice he annihilation at the border between two regions. The radiation signature would be pretty distinct.

Also I think it would be much harder to explain zones of matter and antimatter than to explain a preponderance of one over the other.

Antimatter is not dark matter, definitely not.

[PLOlover]

[ QUOTE ]

if there were significant areas of antimatter then we would notice he annihilation at the border between two regions. The radiation signature would be pretty distinct.

Also I think it would be much harder to explain zones of matter and antimatter than to explain a preponderance of one over the other.

Antimatter is not dark matter, definitely not.

[/ QUOTE ]

as far as I know we can't see the whole universe.
actually as far as border annihalation I'm not sure about that argument. I mean I'm not sure that the argument would apply to all cases.


as far as dark matter, point is that we just don't know as much as we think we do.

[m_the0ry]

annihilation creates some of the most powerful gamma radiation known, it is pretty easy to see where it is occurring in the visible universe.