D O C U M E N T 7 8 J U L Y 1 9 2 0 2 1 1
attaching any reasonable sense to this relation , then I cannot under-
stand them; if anything, only envy
them.[4]
So, once again. In the special theory of relativity both and t are defined as num-
bers that indicate how many periods of a standard clock have elapsed, that is:
t between the space-time epoch nil and the observed point in (space) time;
between the passage of two wave crests by the clock (at rest).
I consistently adhered to this interpretation in the special th. of r. and did not mud-
dle anything up.
dt is a fraction of one period of a standard clock. It is possible to introduce this
concept because, in principle, there exist (short-period) clocks of arbitrary running
speed, with whose aid one can execute that division.
It is different for the general th. of r.; but it is better if we do not go into this much
subtler matter yet before the other one is cleared up.
You are going to think: “Einstein has become a loutish Boche.” All the more am-
icable are my greetings to you, yours,
A. Einstein.
Repent, you hardened
sinner![5]
78. To Gaston Moch
[Berlin,] 19 July 1920
Highly est. S[ir],
Your letter of 3 July was inordinately interesting and appealing to
me.[1]
I am
convinced that you would have translated the booklet masterfully; besides, I must
inform you that I have not heard from Miss Rouvière for a long time and that it has
still not come to a contract with her. I find it very amusing that you know Miss R.
personally so
well.[2]
If she does not insist on doing the translation, I would natu-
rally very much like to leave it to you, under the same [conditions].
The man whom I quoted [and] who jokingly asserted “one should leave elegance
to tailors and shoemakers,” certainly did sport a big, bushy beard, but was no Van-
dal, rather an extremely subtle genius, namely, the Viennese Ludw[ig] Boltzmann,
who discovered the relation between thermodynamic entropy and probability. Inci-
dentally, it should be noted that h[is] lectures and other prose are also very amusing
to
read.[3]
I do not know what sort of a man Pfl[üger] is. (You probably mean the author of
a not badly written popul[ar] work on
relativity.)[4]
I know him neither personally
nor as a scientist.
t t . . . =