Hi all,(adsbygoogle = window.adsbygoogle || []).push({});

I'm trying to follow somebody's derivation for why the existence of magnetic monopoles would demand electric charge was quantised (from http://forum.physorg.com/quantization-of-electric-charge_385.html [Broken]. However I'm having problems with one of their steps.

Halfway through it gets to the action of the electron being equal to e multiplied by the integral of the langrangian * the magnetic vector potential. But then it says that this is equal to e multiplied by the integral of the magnetic vector potential across the boundary of the circle encompassing the Dirac string. How does this follow?:grumpy:

Cheers,

Just some guy

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# Homework Help: Magnetic monopoles and the quantisation of charge

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