At 06:20 PM 5/25/02, you wrote: >Ronn said: > > > Actually, the existence of magnetic monopoles would violate Maxwell's > > equations. > >Indeed. However, the existence of a single magnetic monopole would lead >to the quantisation of charge: for every pair of particles, the product >of the electric charge of one and the magnetic charge of the other must >be an integer multiple of Planck's constant. (The argument leading to >this is originally due to Dirac but there's a particularly clear >version in the chapter on DeRham theory in electromagnetism in Baez and >Muniain's _Gauge Fields, Knots and Gravity_ if anyone's interested.) > >Rich
And it was an attempt to explain why magnetic monopoles may be so rare in reality (an experiment set up to look for them reported one possible hit over 20 years ago, but AFAIK nothing has been seen since then) that initially led Alan Guth to propose the inflationary Universe theory: some proposals suggested that a number of monopoles should have been created in the Big Bang, so there was a fair chance of detecting some, but Guth suggested that after inflation, there might be no more than one monopole in a volume as big as the observable Universe (radius 13 billion l.y. +/-) . . . -- Ronn! :) God bless America, Land that I love! Stand beside her, and guide her Thru the night with a light from above. From the mountains, to the prairies, To the oceans, white with foam� God bless America! My home, sweet home. -- Irving Berlin (1888-1989)
