Longitudinal magnetic forces in conductors

AI Thread Summary
Longitudinal magnetic forces in conductors can lead to wire breakage under high current, independent of melting or pinch effects. This phenomenon may relate to a potential missing term in Maxwell's laws, as suggested by experiments with rail guns. The Maxwell stress tensor could provide a framework for understanding these forces, although some interpretations, such as those by Graneau, have been criticized for overlooking the significance of current direction. Relevant literature includes older and more recent papers that explore these concepts further. Understanding these forces is crucial for advancing electrodynamics theories.
TrickyDicky
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Is there a simple way to understand within classical electrodynamics (or QED) the experiments that show longitudinal forces in conductors that are capable of breaking wires when enough current is conducted and are not due to melting or pinch effect?
 
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I think that this relates to an old issue about a possibly missing term in Maxwell's laws, based on experiments with such things as rail guns.
You can find a rather old paper about it in the Journal of Applied Physics:
http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5114236&abstractAccess=no&userType=inst

I see that this links to a more recent paper by Moyssides, which I had not seen and may give sufficient answer:
http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=1211177&navigation=1
 
Only the first paper seems to be directly related to the OP, anyway I haven't subscriptiom.
I read somewhere these longitudinal forces could be accounted for using the Maxwell stress tensor and I was wondering if anyone knew how.
 
Graneau has misinterpreted his experiments. I looked in detail at his papers some years ago. In each case, the geometry has current moving in a non-longitudinal direction. He considered this negligible but it isn't.
 
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