COHN,EMIL ELECTRODYNAMICS OF MOVING BODIES

A now forgotten figure, Emil Cohn was one of the leading experts in el ectrodynamics at the turn of the century. Unsatisfied with Lorentz's e lectron theory, he proposed an alternative electrodynamics of moving b odies based on a modification of Maxwell's macroscopic field equations that managed to account for all relevant electrodynamic and optical e xperiments, including that of Michelson and Morley. Some of his insigh ts foreshadow aspects of Einstein's relativity theory, especially the elimination of the ether and the criticism of Lorentz's implicit disti nction between true and measured coordinates of space and time. Howeve r, Cohn did not believe in the general validity of the relativity prin ciple, and did not require a revision of the usual concepts of space a nd time. (C) 1995 American Association of Physics Teachers.