5 3 8 D O C U M E N T 2 4 2 D E C E M B E R 1 9 2 0
Deshalb bin ich nicht böse, sondern traurig, denn ich, Ihr wahrer Freund, muss von
diesem Zeugniss gebrauch machen um mich zu verteidigen! Meinerseits, soll ich
Sie biten, nicht böse zu werden. Ihr
Ed. Guillaume
TLS. Genovesi 2000, pp. 105–107. [11 549].
[1]In Doc. 233, to which this is a reply, Einstein had asked Guillaume not to be angry that he had
supplied Grossmann with a statement declaring that he could make no sense of Guillaume’s critique
of relativity theory.
[2]Guillaume refers to an intervention by Grossmann at the International Congress of Mathematics
in Strasbourg, 22–30 September 1920. Guillaume’s lecture is Guillaume 1921.
[3]In Grossmann 1920, Grossmann claimed that the key equation in Guillaume’s argument was an
identity (see Doc. 206 for more on Grossmann’s commentary, and Doc. 77 for Einstein’s reaction to
this part of Guillaume’s theory).
[4]Charles Émile Picard (1856–1941), President of the Congress, was Professor of Analysis and
Higher Algebra at the University of Paris. He was a leading proponent of the boycott of German sci-
entists after World War I (during which all of his three children had perished).
[5]Joseph Louis Lagrange (1736–1813).
[6]Villat 1921, p. xxxiii. The printed version has “doctrine” instead of “théorie” in the first
sentence.
[7]Einstein 1917a (Vol. 6, Doc. 42), pp. 16–19.
[8]The emission hypothesis refers to the supposition that the velocity of light depends on the veloc-
ity of its source.
[9]Guillaume advances this claim that the shape of the expanding wavefront of light appears dif-
ferent to different inertial observers as a counterargument against the principle of the constancy of the
velocity of light. He put forward the argument for the special theory in Guillaume 1920b, and for the
general theory in Guillaume and Willigens 1920.
242. From Albert G. Schmedeman
Christiania, December 23, 1920.
Dear Professor Einstein:
In reply to your letter of the 16th in which you inform me that the proposal made
by the University of Wisconsin is acceptable to you providing satisfactory terms
can be arranged by Mr. Paul Wahrburg or some one
else,[1]
I have to inform you
that I have telegraphed this information to the regents of the University of Wis-
consin.[2]
I quite agree with you that it would be impossible for you to arrange a series of
lectures, and your suggestion that Mr. Wahrburg arrange this matter for you is an
excellent idea and I hope that satisfactory arrangements can be made for you to
come to the United
States.[3]
I am sure that you will receive a splendid welcome by
the American people and that they are anxious to both see and hear you.
If arrangements are made for you to come to the University of Wisconsin, as I