One century later: Remarks on the Barnett experiment

Abstract

The Barnett experiment (the rotation of either a solenoid or a short-circuited cylindrical capacitor about a common axis) was performed at the beginning of the 20th century to choose between the Hertz, Maxwell, or Lorentz electrodynamics theories. The results obtained by Barnett led him to conclude that both the electrodynamics of Hertz and Maxwell should be rejected, while Lorentz was solely correct. We analyze this experiment from a modern point of view and show that the results can be explained within the framework of Maxwell electrodynamics and relativity theory. However, the explanation still has some physical difficulties.