Friday, September 04, 2009

'Overwhelming' Evidence for Monopoles?

A flurry of papers being published and appearing on Arxiv seem to claim the discovery of monopoles {link available for free only for a limited time}, but it is not where you think.

"People have been looking for monopoles in cosmic rays and particle accelerators — even Moon rocks," says Jonathan Morris, a researcher at the Helmholtz Centre for Materials and Energy in Berlin.

Now Morris and others have found the strongest evidence yet for magnetic monopoles, in small crystals about the size of an ear plug. When the crystals are chilled to near absolute zero, they seem to fill with tiny single points of north and south. The points are less than a nanometre apart, and cannot be measured directly. Nevertheless, Morris and other physicists believe they are there. They make their case in two papers published today in the journal Science, and other work published on the pre-print server arXiv.org.


Here are the references:

1. Kadowaki, H. et al. preprint at http://arXiv.org/abs/0908.3568v2 (2009).
2. Fennell, T. et al. Science advance online publication doi:10.1126/science.1177582 (2009).
3. Kadowaki, H. et al. preprint at http://arXiv.org/abs/0908.3568v2 (2009).
4. Bramwell, S. T. et al. preprint at http://arxiv.org/abs/0907.0956 (2009).

It remains to be seen whether these monopoles from the "spin ice" system can actually be considered as the actual monopoles that we've been looking for (don't think this is what the Standard Model had in mind).

Not surprisingly, such a fundamental discovery came, not from cosmic rays or particle accelerators, but from condensed matter physics! There should be no more question on whether CMP studies "fundamental" ideas or not. It should be patently clear already by now.

Edit: adding the link from ScienceNOW on the same topic.

Edit 10/15/09: S.T. Bramwell paper has now appeared in Nature. The exact reference is: S.T. Bramwell et al., Nature v.461, p.956 (2009).

Zz.

5 comments:

Anonymous said...

From what I can tell, it doesn't look like these are 'fundamental' magnetic monopoles.

Joseph Smidt said...

If bona fide magnetic monopoles are discovered it would be big news indeed. Theorists might go nuts. :) Thanks for the heads up.

Yeah, condensed matter seems to be a treasure trove of potentially incredible things. I will laugh if main of the main "missing pieces" of theoretical physics are not to be found in particle accelerators, but in condensed matter.

Anonymous said...

They may not be the same monopoles people have been expecting (as in monopolar quanta), but a monopole is a monopole just the same. I would consider this an important discovery.

Gordon Stangler said...

I agree and disagree with Anon. A monopole is a monopole. I think that it may in fact be the "fundamental" monopole particle physics is looking for, since it appears these monopoles cannot be transformed away into electric current.

ZapperZ said...

Well, you gotta be careful here. Condensed matter system, under collective interactions, can produce many things, such as fractional charge. But these things disappear as you try to pick the apart, i.e. they are EMERGENT phenomena.

Are they "fundamental"? Sure they are, since they give the same in-depth insight into many of the analogous physics of our fundamental particles. But it would be wrong to think that they are equivalent to the fundamental particles. One could say that the mathematics are equivalent, the same way the mathematics found in condensed matter systems are equivalent to the Higgs mechanism. But it would be a bit misleading to say that these are the same thing that we are looking for in elementary particle physics.

Zz.