7 8 D O C . 1 5 C O M M E N T O N N O T E B Y G E H R C K E
15. “Comment on E. Gehrcke’s Note,
‘On the Ether’”1
[Einstein 1918l]
Received 29 November 1918
Published 30 December 1918
In: Deutsche Physikalische Gesellschaft. Verhandlungen 20 (1918): 261.
In the note referred to here, the claim is made that the aberration could be explained
by the theory that light ether co-moves with matter. This claim is based upon a the-
ory by Stokes, which has been briefly discussed by Drude in the third edition of his
Optik. In consideration of the subject matter and the authority of Stokes, I deem it
necessary to point out that this theory is untenable because it is based upon contra-
dictory assumptions. Because, if the ether is carried with the celestial bodies, its ve-
locity vector cannot be curl-free (and continuous) as is required by Stokes’s deri-
vation of the law of aberration; this follows from the well-known theorems of the
potential theory.
In truth, the hypothesis of an ether co-moving together with celestial bodies is
incompatible with the law of aberration.
1
These Verhandl. 20 (1918), pp. 165–169. [1]
[2]
[3]
[4]