Is movenent of magnetic moment affected by electric field?

[Duda Jarek]

Physical effects relating electric and magnetic properties have sometimes 'dual' analogues - with exchanged places.

For example in Aharonov-Bohm effect, the phase of charged particle depends on side of magnetic flux tube it comes through, while in its 'dual' analogue: Aharonov-Casher, the particle has magnetic moment and tube contains line of charge (it was used e.g. for neutron interference).

Another interesting 'dual' effect (hypothetical) can be found in magnetic monopole Wikipedia article - full expression for Lorenz force in such case would be: [math]\mathbf{F}=q_e\left(\mathbf{E}+\frac{\mathbf{v}}{c}\times \mathbf{B}\right)+q_m\left(\mathbf{B}- \frac{\mathbf{v}}{c}\times \mathbf{E}\right)[/math]

where [math]q_m[/math] is magnetic charge - the last term corresponds to magnetic monopole - electric field iteration.

 

The question is if we should expect similar term for not only magnetic monopoles, but also for much more common: magnetic moments(dipoles)?

I would say that yes - for example imagine classical electron traveling in proton's electron field - let's change reference frame such that for infinitesimal time electron stops and proton is moving in also magnetic field created by quite large electron's magnetic moment - because of 3rd Newton's law, resulting Lorentz force should also work on electron ...

(3) equation here is Lagrangian for such electron's movement: [math] \mathbf{L} = \frac{1}{2}m\mathbf{v}^2+\frac{Ze^2}{r}+\frac{Ze}{c}\left[ \mathbf{v}\cdot\left( \frac{\mu\times \mathbf{r}}{r^3}\right)\right] [/math]

where the last term would correspond to such eventual magnetic moment-electric field interaction.

But in recent discussion, swansont's only counterargument was based on that such force doesn't exist...

 

So I wanted to ask if this looking quite important force is true or not?

If true, it seems to be completely forgotten - there would be needed some better sources ... have you seen something like that in a book or paper?

Edited February 23, 2011 by Duda Jarek

[swansont]

But in recent discussion, swansont's only counterargument was based on that such force doesn't exist...

 

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Moderator Note

Don't strawman my argument, and don't use a mainstream thread to advertise speculative material. Both are against the rules.

[Duda Jarek]

I had to check what 'strawman argument' means ("A straw man argument is an informal fallacy based on misrepresentation of an opponent's position(...).") - at the end of that discussion you write "Yes, it is interesting. But it fails to work in fatal ways." supporting the last sentence by that for nucleus without magnetic moment, there would be no Lorentz force to repel electron - I've replied that there is also magnetic field of thousands times larger magnetic moment of electron (this is the Lorentz force used in that model), but I didn't get any further reply? Please explain why do you think I've misrepresented your position? (but let's take it back to that discussion)

 

Question from this thread is looking important extremely general question - if you don't like microscopic scales, let's imagine we have bar magnet traveling in electric field ... again we could center reference frame on the magnet for a moment and now the charged object is traveling in magnetic field generated by the magnet ...

So let's forget about the 'speculative' microscopic use in this thread - what do you generally think of existence of such force?

Dipole can be seen as made of two near monopoles - if you don't think such force exists for magnetic dipoles, what about for eventual monopoles (I can find you some papers about it)?

 

ps. Quantum mechanics was built on classical one, so there should be some quantum effects corresponding to the last term from Lagrangian above (making Bohr's orbits unstable) - atomic spin-orbit interaction seems to be one of them (?)

Edited February 24, 2011 by Duda Jarek