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A concise introduction to Colombeau generalized functions and their applications in classical electrodynamics

Andre Gsponer
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Abstract

The objective of this introduction to Colombeau algebras of generalized-functions (in which distributions can be freely multiplied) is to explain in elementary terms the essential concepts necessary for their application to basic non-linear problems in classical physics. Examples are given in hydrodynamics and electrodynamics. The problem of the self-energy of a point electric charge is worked out in detail: The Coulomb potential and field are defined as Colombeau generalized-functions, and integrals of nonlinear expressions corresponding to products of distributions (such as the square of the Coulomb field and the square of the delta-function) are calculated. Finally, the methods introduced in Eur. J. Phys. /28/ (2007) 267-275, 1021-1042, and 1241, to deal with point-like singularities in classical electrodynamics are confirmed.

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Andre Gsponer. 2008-10-02. A concise introduction to Colombeau generalized functions and their applications in classical electrodynamics. https://doi.org/10.1088/0143-0807%2F30%2F1%2F11

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