1 8 0 D O C U M E N T 1 7 9 D E C E M B E R 1 9 2 3
out to be the solution to (II), with suitable choice of . The sought-after
system is supposed to be derived by generalizing (II) with these constants.
satisfies the Bianchi (Struik)
identity[5]
.
Hence it follows from II:
(III)
These are supposed to be the sought-after equations in connection with the pre-
vious field equations (I), likewise contained in (II). One knows L(m,o and L(o,ε)
are solutions to (III)–(I) and one expects that generally L(mε) would be the general
solution. To be investigated is whether (I)–(III) does justice to the facts of quanta.
Good luck and cordial regards, yours,
Einstein.
P. S. If you see anyone from the Rockefeller Foundation, then ask whether it
wouldn’t perhaps grant me 600 dollars per year for a mathematical
assistant.[6]
179. To Elsa Einstein
[Ede,] Thursday [20 December 1923]
Dear Else,
I’ve been at the de Ridders’, on the country estate near Ede, since Tuesday eve-
ning; an enviable
existence.[1]
Tomorrow it’s off to Eindhoven. In the evening, lec-
ture for the factory’s
engineers.[2]
Saturday night I will probably travel to Berlin
(arrival Sunday morning 8:07). But I can’t say for sure because I don’t know if I
can get away from Eindhoven again so quickly. Even though I am such an inveter-
ate roamer, I am sill looking forward to coming home. During the good-byes, the
Ehrenfest children wished me another putsch
soon[3]
– it was a merry life over
there. Hopefully the miracle doctor has meanwhile helped Ilse so that she can enjoy
herself
again.[4]
In Berlin the general situation doesn’t seem to be improving, like-
wise the general political situation of Germany. Severe though France’s conditions
may
be,[5]
ultimately, agreement does benefit the more diligent.
To a happy reunion with you all your
Albert.
A′A″A′″
Rik,
lm
Riklm
;n
Rik,mn
;l
Rik
nl m ;,
+ + 0 ≡
Φik
lm n ;,
Φikmn
;l
Φiknl;m + + 0 =