Talk:Dipole

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Vector field equations[edit]

In the section for the electric dipole it says that the equation is formally identical to the one for the magnetic dipole. Of course this has to be true, so I just wanted to rearrange the equations to bring out this correspondence clearly (pulling r^3 out of the parentheses). But then I saw this Dirac's delta-term. Can anybody tell me where it would actually make sense to define the field like that? As I see it, only having the first term would be completely fine, a continuous function multiplied by r^(-3). Also note that the second term has no negative power of r, so this term is actually completely swamped by the first. Apart from that, its prefactor is not consistent with the one of the magnetic dipole. So I would just delete this term in both the magnetic and electric formula, just as I find it in Classical Electrodynamics by Jackson or the german or italian wikipedia. Seattle Jörg (talk) 07:02, 16 July 2012 (UTC)

Have a look at Magnetic_moment#Internal_magnetic_field_of_a_dipole. RockMagnetist (talk) 16:31, 16 July 2012 (UTC)
OK, I see sense in that. Is there a reference? Otherwise I would have to reproduce it by hand. Seattle Jörg (talk) 12:38, 6 August 2012 (UTC)
I have added citations. Unfortunately, I don't have the page numbers for the Brown citations because I didn't add them at the time and now I don't have the book. I'll try to get hold of it again. RockMagnetist (talk) 17:07, 6 August 2012 (UTC)