Apparent Baryonic/Antibaryonic Asymmetry

[primummobile]

I remember reading a few years ago about experiments being undertaken to determine if there existed a dipole moment in electrons that would cause matter and antimatter to decay at different rates... but I can't find literature on it. I was wondering if anyone could direct me to somewhere that may have information on this or tell me about any results to date.

[Shaula]

Electrons are stable, so not sure how their dipole moment would affect things. CP violation is the main mechanism for introducing this asymmetry that we know of and it is only seen in Weak force interactions. There are lots of interesting results on this, first using Kaons and then B-mesons (in experiments like BELLE and BaBAR)

[primummobile]

I agree with that. But I've always read that the standard model only offers two methods of breaking CP symmetry. One, through quantum chromodynamics, has (to my knowledge) never been observed. The other is the weak force interactions you are speaking about. But, isn't CP violation due to Weak force interactions too little to account for the mass of observed baryonic matter in the universe? I was thinking that there would need to be some additional element at play.

I know I read about an experiment involving electron dipole moments. It may have been in National Geographic. I'm probably just looking into a dead end here, and that's why I can't find any follow up. The more obvious answer is probably that the standard model is deficient in symmetry-breaking predictions.

[primummobile]

I found the article, and it was in National Geographic. Here is the relevent portion:

The new electron property may help explain the matter-antimatter imbalance. The theory is that electrons have what's called an electric dipole moment, which is similar to the separation between the positive and negative poles of a magnet.

In the case of an electron, which carries only a negative charge, the electric dipole represents an unequal distribution of the charge.

"One can imagine the dipole moment as a slight spatial deformation of this negative charge," Ležaić said. Such a deformation would violate the symmetry between matter and antimatter, making it possible that particles and antiparticles decay—spontaneously turn into other kinds of particles—at different rates.

It goes on to describe experiments beginning in 2010 in Germany. I suppose the lack of follow-up information indicates no data to date?

Here is the link to the article:

http://news.nationalgeographic.com/n...ter-imbalance/

EDIT: I guess the experiments were conducted at Yale University, not Germany.

[Shaula]

When you get back into eras of the universe we really don't have a good handle on the Strong and Weak forces merge. No one knows how this affects the CP violation mechanism. So we can say that if the universe was filled with equal numbers of each type of particle at the point where our models work again then it is deficient in ways to generate enough asymmetry. But there is this blank patch before that.

BTW: Google is your friend: Article

No detail on the theory in the article, no links to the papers (other than one on materials). So I cannot really comment about it much.

[primummobile]

When you get back into eras of the universe we really don't have a good handle on the Strong and Weak forces merge. No one knows how this affects the CP violation mechanism. So we can say that if the universe was filled with equal numbers of each type of particle at the point where our models work again then it is deficient in ways to generate enough asymmetry. But there is this blank patch before that.

I realize that. It just seemed to me, at the time, that this was a promising direction to take in filling in the blank patch. I've done a little work with electric dipole moments, and I thought this idea fascinating.