

The Hunt for the Magnetic Monopole (2013) - ColinCochrane
http://spectrum.ieee.org/semiconductors/materials/the-hunt-for-the-magnetic-monopole

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pontifier
My understanding of magnetism is that exists solely as a placeholder to
reconcile the different ways charge movements look for observers in
relativistic frames...

In looking at spin ice, I'm struck by the similarity between the "trail" or
"string" between monopoles and the way long bar magnets behave. As a bar
magnet gets longer it behaves more and more like 2 monopoles separated by the
bar.

Here's a little gedanken. Imagine a south magnetic monopole did exist as a
single particle at (0,0,0). I'm thinking of the force it would exert on a
charged particle (a proton for example) at (1,0,0) moving in the positive Y
direction. The magnetic field would point at the origin, and a force would
tend to push the particle out of the page... in order for angular momentum to
be conserved, the monopole must now spin. If we ignore conservation of angular
momentum, and just stick to regular momentum it must still move in the
opposite direction of the force on the proton so it would create a sort of
weird unequal orbit around a common axis.

It's fun to think about these things.

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pontifier
A little more gedanken, if a monopole is massless, it might behave a bit like
a photon and be very difficult to "find" in any particular location.

