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Averaging of harmonic physical fields over an annular region enclosing field sources
1Metabolic Magnetic Resonance Research and Computing Center, Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104.
Abstract:
Fields such as temperature, current density, and static electromagnetic fields in regions with no field sources are harmonic functions that satisfy the Laplace equation. Such functions on a sphere have a well-known mean value property. A new mean value property is derived for fields that are harmonic on an annular region, with the field sources enclosed by the inner boundary. Some examples are discussed.
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