Among other things, these effects would include the quantum counterpart of the electromagnetic back-reaction that so vexed classical theorists of electromagnetism.
He has been author of about fifty works in the fields of mathematical analysis, analytical mechanics and mathematical-physics (elasticity and electromagnetism).
He is sensitive to electromagnetism -- a syndrome that could be entirely psychosomatic -- and wraps himself in a metallic space blanket when the signal is fraying his nerves most.
Reciprocity is useful in optics, which (apart from quantum effects) can be expressed in terms of classical electromagnetism, but also in terms of radiometry.