Monopoles!

TallDave · Post by **TallDave** » Mon Sep 07, 2009 5:58 am

http://www.sciencedaily.com/releases/20 ... 163725.htm

Jonathan Morris, Alan Tennant and colleagues (HZB) undertook a neutron scattering experiment at the Berlin research reactor. The material under investigation was a single crystal of Dysprosium Titanate. This material crystallises in a quite remarkable geometry, the so called pyrochlore-lattice. With the help of neutron scattering Morris and Tennant show that the magnetic moments inside the material had reorganised into so-called 'spin-spaghetti'. This name comes from the ordering of the dipoles themselves, such that a network of contorted tubes (strings) develops, through which magnetic flux is transported. These can be made visible by their interaction with the neutrons which themselves carry a magnetic moment. Thus the neutrons scatter as a reciprocal representation of the Strings.

During the neutron scattering measurements a magnetic field was applied to the crystal by the researchers. With this field they could influence the symmetry and orientation of the strings. Thereby it was possible to reduce the density of the string networks and promote the monopole dissociation. As a result, at temperatures from 0.6 to 2 Kelvin, the strings are visible and have magnetic monopoles at their ends.

The signature of a gas made up by these monopoles has also been observed in heat capacity measured by Bastian Klemke (HZB). Providing further confirmation of the existence of monopoles and showing that they interact in the same way as electric charges.

Skipjack · Post by **Skipjack** » Mon Sep 07, 2009 6:50 am

I saw that, even thought about posting it here. I am just not sure what it does that would help with anything fusion related. It is still pretty cool though.

kcdodd · Post by **kcdodd** » Mon Sep 07, 2009 8:49 pm

I don't understand. *what* is the magnetic monopole?

djolds1 · Post by **djolds1** » Mon Sep 07, 2009 9:15 pm

Skipjack wrote:I saw that, even thought about posting it here. I am just not sure what it does that would help with anything fusion related. It is still pretty cool though.

The imagineers at orionsarm think actual monopoles would be usable:

http://www.orionsarm.com/eg-article/46411e9d02b29

OTOH, I ran across an analysis of this stating that these aren't quite "true" monopoles.

Professor Science · Post by **Professor Science** » Mon Sep 07, 2009 9:53 pm

Yeah, they're not particles with disctinct magnetic charge, they're materials with net zero magnetic charge, but regions of net postive or negative. Which is unusual, but alas, not terribly usable yet.

kunkmiester · Post by **kunkmiester** » Tue Sep 08, 2009 12:28 am

More esoterically, if you can create a magnetic monopole, that it's possible that gravity is similar, with most particles being monopole, but under certain conditions you could create particles that are gravitationally dipolar, much like you're doing the opposite here.

MSimon · Post by **MSimon** » Tue Sep 08, 2009 12:44 am

Professor Science wrote:Yeah, they're not particles with disctinct magnetic charge, they're materials with net zero magnetic charge, but regions of net postive or negative. Which is unusual, but alas, not terribly usable yet.

I wonder if it is more on the lines of a micro Halbach array.

kcdodd · Post by **kcdodd** » Tue Sep 08, 2009 3:29 am

I don't understand how you can say they are monopoles. Is the divergence not still zero, or the equivalent surface integral around the so-call emergent magnetic charge. If they are really monopoles, you should be able to represent any monopole charge as an emergent field of a dipole spaghetti transporting flux in some hidden fashion to which Maxwell equation still holds. Otherwise it's not equivalent is it?

Art Carlson · Post by **Art Carlson** » Tue Sep 08, 2009 7:53 am

I remember hearing many years ago that magnetic monopoles would have far reaching technological consequences, like super compact motors. Even if these critters are not actually magnetically charged particles, could they be used to build things anyway? After all, electric motors don't have a net electric charge either. (To maintain a tenuous connection to the topic of this forum, let me gratuitously mention the word "quasi-neutrality".)