4 5 6 D O C U M E N T 3 3 5 M A R C H 1 9 2 0
TLS. [43 687].
[1]Unknown, but see note 3.
[2]Weyl 1918b.
[3]Hans Reissner (1874–1967), Professor of Mechanics at the Technical University of Berlin-
Charlottenburg, communicated a paper on “Weyl’s Extension of Einstein’s Relativity Theory” (“Die
Weylsche Ergänzung der Einsteinschen Relativitätstheorie”) to the Berlin Mathematical Society
(Berliner Mathematische Gesellschaft, BMG) in its session of 28 January 1920 (see Sitzungsberichte
of the BMG 19 (1920), p. 2). The discussion of Reissner’s paper was continued at the BMG meeting
of 25 February, with a paper by Georg Hamel (1877–1954), Professor of Mathematics at the Technical
University of Berlin-Charlottenburg, on “Some Fundamental Remarks on the Relativity Principle”
(“Einige grundsätzliche Bemerkungen zum Relativitätsprinzip,” ibid. p. 3). Both papers were pub-
lished (see Reissner 1920 and Hamel 1920). Fleck had himself presented a paper on a number theo-
retical problem (Fleck 1920) in an earlier session of the BMG, of which he was listed as a member
(see Sitzungsberichte of the BMG 19 (1920), pp. 2, 90).
[4]At this paragraph in the original text Einstein indicates a note that he appended at the left margin
of the document: “Nein.”
[5]It is not clear what Fleck understands under the “order” of a manifold and what theorem he is
referring to. Locally, any Riemannian manifold of dimension n with analytic metric g of
signature (p,q) can be embedded analytically and isometrically in a manifold , where
, , . See Goenner 1980 for a more detailed discussion. For a review of some
results on global embedding of Riemannian manifolds, see Friedman, A. 1965.
[6]Recall that c is the conventional symbol for the speed of light.
[7]At this paragraph in the original text Einstein indicates a note that he appended at the left margin
of the document: “Wir könnten das andere System nicht sehen, wenn es thatsächlich geschlossen
wäre.”
[8]At this paragraph in the original text Einstein indicates a remark that he appended at the left mar-
gin of the document: “aus dem gl. Grunde unmöglich.”
[9]Einstein, as his marginal comments suggest, could not be sympathetic to the notion that the uni-
verse was constructed out of closed or quasi-closed systems, since he viewed general relativity as a
theory intimately concerned with how the properties of matter, such as inertia itself, arise out of the
interactions of all the matter in the universe, a point of view he referred to as Mach’s principle.
[10]At this point in the original text Fleck indicates a note that he appended at the left margin of the
document: “und Radioaktivität.”
335. To Paul Ehrenfest
[Berlin, 1 March
1920][1]
Lieber Ehrenfest!
Ich schreibe jetzt erst, weil ich durch die schwere Kankheit meiner Mutter wie
gelähmt war. Vor einer Woche haben wir sie zu Grabe getragen.[2] Es war eine
furchtbare Zeit!—
Nun schreibe ich die Antrittsvorlesung.[3] Das Semester geht hier noch bis Ende
März.[4] Wann soll ich nach Holland kommen? Ich freue mich schon sehr auf die
Antrittsvorlesung und überhaupt auf unser Wiedersehen. Der Geigenbauer bockt,
statt zu schaffen; er ist eben ein versoffenes Luder— Du würdest Deine Freude an
dem Kerl haben; aber ich fürchte, dass wir die Geigen nicht rechtzeitig kriegen.[5]
Meine Rechnung war grandios. Man hat in dieser Pleite jedes Gefühl für Zehner-
Mn(p, q)
Mm(r
s) ,
m
n 1⎞ +
2
⎝ ⎠
⎛
≥ r p ≥ s q ≥