Making Magnetic Monopoles and Other Physics Exotica
PhysicsDavid writes "Physicists have been searching for magnetic monopoles pretty much since they knew about magnetism and definitely since Maxwell unified electricity and magnetism. Now some researchers have shown that using some weird mirror materials will allow them to create something indistinguishable from a monopole in a lab experiment. A paper about it was published today in the journal Science as an advance online publication (abstract; full article available only to AAAS members). The technique looks like it could be used to create analog systems of other kinds of exotic particles that haven't yet been observed, such as axions. The theorists who proposed this are working with experimenters to try to create these systems and study them in depth this year."
div B = 0
equation were modified to read, say
div B = rho_m / mu_0
in analogy to Gauss' law. The defining qualities of Maxwell's model, such as the compliance with relativity, would remain intact.
For further reading on this, David J. Griffiths' 'Introduction to Electrodynamics' is many a professor's first recommendation to students.
If it turns out that you can create something indistinguishable from a magnetic monopole, then we have to start some very serious research into the implications.
This is "indistinguishable" from a monopole in the same way that an image in a mirror is "indistinguishable" from the real object. While extremely interesting there will be bound to be edge effects given the finite size of the mirror and there must physically be a second pole somewhere because the material cannot spontaneously acquire a net magnetic charge...unless there is some significant new physics occuring. Hence I would take "indistinguishable" with a very large grain of salt. It is an extremely interesting result though.
Back when I was designing magnetic bubble memory we used to use monopole equations to represent the bubbles.
No violation of physics here because they were always paired. But the pairs in the media are well separated so it's a btter approximation to use two monopoles than a dipole.
That is to say, each bubble is really a cyllinder running from the bottom of the thin film to the top just like it is in vertical recording HD. You can treat the top as a monopole and the bottom as an opposite monopole and get a very good model of bubble-to-bubble interactions.
Some drink at the fountain of knowledge. Others just gargle.