clipka wrote:
> Kevin Wampler schrieb:
>> I think that this paper gives this argument, although it's a bit 
>> lacking in details for my taste:
>>
>> http://www.iop.org/EJ/abstract/0143-0807/29/5/002
> 
> I'm not buying that, literally ;-)
> 
> (How I hate this practice of making scientific papers available only for 
> money...)

Me too, I didn't realize that it was access-restricted.  The title was 
"Lorentz contraction and current-carrying wires" in case you can find it 
elsewhere.  It's not a research paper anyway, and they just give an 
example where what appears an a purely magnetic force in one frame can't 
be reduced to a purely electric force, but only to different mixes of 
electric and magentic forces.

I'll just quote a bit from the introduction and the conclusion:

"This sets the scene for the following argument. Imagine a charged 
particle q moving parallel to the current-carrying wire at the electron 
drift velocity1 . In the ion frame, the interaction between the wire and 
the charged particle is described in terms of magnetostatics. In the 
electron frame, this interaction is described in terms of 
electrostatics—see figure 1.  Special relativity is then invoked to show 
that the two expressions can be transformed into one another.

Unless warned explicitly, a student following this line of thought may 
well be left with the impression that either electrostatics or 
magnetostatics is redundant. In this paper, I will use the closely 
related example of the force between two parallel wires carrying equal 
currents in the same direction to illustrate that both electrostatics 
and magnetostatics need to be retained."
...
"This derivation shows that the force between two parallel 
current-carrying wires is purely magnetostatic in the rest frame of the 
wires, but is a combination of electrostatic and magnetostatic forces in 
the electron frame. This result should serve to dispel any notion of 
redundancy of electrostatics or magnetostatics. While the derivation is 
primarily aimed at the introductory undergraduate level, it could also 
serve to limit the risk of seeing electromagnetic fields as something 
that can only be done in the context of antisymmetric second-rank 
tensors in higher level courses."


I don't have any idea how much to trust the author's conclusions though, 
and I've had an irritatingly difficult time finding a definitive answer 
on Google from a source I feel I can trust more.

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