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arXiv · 2108.02896

Electromagnetic force and torque derived from a Lagrangian in conjunction with the Maxwell-Lorentz equations

Masud Mansuripur
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Abstract

Electromagnetic force and torque are typically derived from a stress tensor in conjunction with Maxwell's equations of classical electrodynamics. In some instances, the Principle of Least Action (built around a Lagrangian) can be used to arrive at the same mathematical expressions of force and torque as those derived from a stress tensor. This paper describes some of the underlying arguments for the existence of a Lagrangian in the case of certain simple physical systems. While some formulations of electromagnetic force and torque admit a Lagrangian, there are other formulations for which a Lagrangian may not exist.

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Masud Mansuripur. 2021-08-06. Electromagnetic force and torque derived from a Lagrangian in conjunction with the Maxwell-Lorentz equations. https://doi.org/10.1117/12.2595187

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