3 7 0 D O C U M E N T S 3 1 5 , 3 1 6 D E C E M B E R 1 9 2 1
what is nowadays known as the event horizon of a black hole. In his paper, Painlevé does not remark
upon this, except to note that, with his coordinates (nowadays usually referred to as Gullstrand-
Painlevé coordinates), objects do not become distorted in shape as they approach the Sun. This is
because the observer in these coordinates is also approaching the Sun. The famous effects seen in the
Schwarzschild coordinates are those that are observed by someone remaining at a great distance from
the Sun. Painlevé, seeing the difference in measurements implied by the two coordinate systems
describing the same physical system, advanced this as evidence that the metric ds could not be phys-
ically meaningful, as claimed by Einstein’s theory: “My conclusion is that it is pure fantasy to claim
that consequences of this kind can be drawn” (“Ma conclusion c’est que c’est pure imagination de
pretendre tirer des consequences de cette nature”). For further historical discussion, see Eisenstaedt
1982, pp. 173–177.
315. From Maja Winteler-Einstein
Fiesole, 8 via Verdi, 7. XII. [1921]
Lieber Albert!
Am 28. Nov. war die Sache, die wir zu besorgen hatten,
erledigt.[1]
Ich gebe erst
heute Nachricht, weil Pauli seit 1 1/2 Wochen an schwerer Brustfellentzündung
darniederligt. Er hat sehr hohes Fieber, u. ich habe viel zu denken u. zu sorgen. Er
hat sich wohl auf der Heimkehr aus der Schweiz die Krankheit eingezogen, da die
italienischen Wagen nicht geheizt waren.
Herzliche Grüße an alle, einen Kuß für Dich.
Maja.
AKS. [144 804]. The postcard is addressed “Herrn Prof. Dr. Albert Einstein Haberlandstr 5 Berlin W.
30,” and postmarked “Fiesole (Firenze) –7. 12. 21.” The verso depicts the Arno embankment with the
Santa Trinità bridge.
[1]Most likely a reference to the visit to Zurich by Paul Winteler in regard to the shares of the Schwei-
zerische Auer-Aktien-Gesellschaft and to the possible sale of their house in Lucerne (see Docs. 167
and 297).
316. From Walther Bothe[1]
[Berlin,] Charlottenburg, den 7. Dez. 1921. Werner-Siemensstr. 8/12.
Sehr verehrter Herr Professor!
Die Bemerkung, die ich mir heute am Telefon zu machen erlaubte, bezog sich
auf folgendes. Die Winkelablenkung der Wellennormalen ist
zweifellos[2]
.
dn-
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