Current Concentrated Along Axis

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Current in a fat wire is theorized to concentrate along the wire's axis due to the attraction between parallel wires. However, there are concerns about why this concentration might not occur, with suggestions of electric repulsion among conduction particles. The discussion touches on the implications of this behavior for electric fields, specifically that a curl in the current density would contradict the fact that the curl of an electric field is zero. Participants express confusion about the underlying physics and seek clarification on Griffiths' theories. Understanding these dynamics is crucial for deeper insights into electrical conduction in wires.
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Griffiths brings up a point that it might make sense that current in a fat wire would want to concentrate itself mainly along the axis of the wire, given that parallel wires attract each other.

He then asks us to figure out why this might not happen, but to be honest I would think it should! The only thing I can think of is some sort of electric repulsion in the conduction particles' rest frame, but I feel like there are more subtle points in transforming the frames like this. Where am I going wrong?
 
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hi there :)

who is Griffiths and do you have a link to his study ?

Dave
 
That would give j a curl. Since j=\sigma E, that would give E a curl, but curl E=0.
 
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