DOCUMENT
254 SEPTEMBER 1916 333
lationstheoretisch
dargestellt
sind,
wie ja
überhaupt
der
Begriff
der
Frequenz.[6]
Wesentlich aber
ist,
dass die statistische
Betrachtung,
welche
zu
Plancks Formel
führt,
einheitlich
geworden
ist,
und
dabei
denkbar
allgemein,
indem
über
die
spe-
zielle Beschaffenheit der vermittelnden
Moleküle
nichts mehr
vorausgesetzt
wird
als die
allgemeinste Quantenidee.[7]
Dabei
ergibt
sich das
(noch
nicht in
der Dir
gesandten
Arbeit
enthaltene)
Resultat,
dass bei
jeder
elementaren
Energieübertra-
gung
zwischen
Strahrung
und
Materie der
Impulsbetrag
hv/c
auf
das
Molekül über-
geht.[8]
Daraus
folgt,
dass
jeder
solche
Elementarprozess
ein
vollständig gerichte-
ter
Vorgang
ist. Damit sind die
Lichtquanten so
gut
wie
gesichert.
Die Reise
zu
Lorentz
werde
ich versuchen.[9]
Dazu
brauche ich meinen
Heimat-
schein
im
Original.
Ich schrieb nach Zürich darnach und
bat,
das
Papier
Dir
zu
sen-
den,
falls das
Zivilstands-Amt
Sendungen
nach
dem
Ausland
nicht übernimmt. Sei
so gut,
und
sende
mir
in
diesem
Falle das
Papier umgehend.[10]
Mir
besten Grüssen
an
Dich und
die Deinen Dein
Albert.
Bei
wem
wohnst Du
und
was
fesselt Dich für
so lange
Zeit nach Bern?
ALS
(SzGB).
Einstein/Besso
1972,
25
(E. 20).
[7
289].
[1]Einstein
may
have
been
serving as a
conduit for
to Ugo
Russi,
who
was
in
a
refugee
camp
in
Austria
(see
Doc.
250).
[2]Perhaps indicating a more
hopeful
prognosis
for
Einstein-Maric’s condition than that
given
in
Docs. 251 and 252.
[3]Einstein
was unalterably
determined
to seek
a
divorce in
mid-July
(see
Doc.
233).
[4]In mid-March,
Einstein had attributed his decision
to
obtain
a
divorce and
remarry
in
part
to
fears in the
family
that his
own
marital limbo
was
compromising
Ilse Einstein’s
eligibility
for
mar-
riage (see
Doc.
200).
At
the
beginning
of
the
year,
however,
he had boasted that he
was
standing
firm
against
the wishes
of
his relatives in his decision not to
remarry
(see
Doc.
178). By
late
July,
he
alluded to the fact that he had
reconsidered
yet again
(see
Doc.
238).
[5]
Several
years
earlier,
Einstein had
attached
some
theoretical
significance
to
the
proportionality
mentioned
here:
see
Einstein 1909b
(Vol.
2,
Doc.
56),
sec. 10,
and his comments in
Einstein
to H. A.
Lorentz,
30
March
1909 and 23
May
1909
(Vol.
5,
Docs. 146 and
163).
[6]In Doc. 251, Einstein
had
emphasized
that his
new
derivation
of
Planck’s
formula
is free
of
wave-theoretical considerations.
[7]The
derivation is
presented
in Einstein
1916j
(Vol.
6,
Doc.
34), an offprint
of which Einstein had
sent to Besso
(see
Doc.
251).
The “quantum idea” is that
a
molecule
can
only
assume a
discrete
series
of
energy
states.
[8]This
result
is first
presented
in
Einstein 1916n
(Vol. 6,
Doc.
38).
[9]Two
weeks
earlier,
Einstein had
informed Besso
that he
would travel to the Netherlands
only
when
peace came
(see
Doc.
251),
but
the
possibility
of
receiving
an
official invitation
(see
the
pre-
ceding document)
may
have renewed his determination to
visit Dutch
colleagues.
[10]Zurich
municipal
citizenship
was
conferred
on
Einstein
in
February
1901
(see
the editorial
note,
“Swiss
Citizenship,”
Vol.
1, pp.
239-241). A certificate
of
citizenship
is called
a
Heimatschein
in Switzerland.