3 6 V O L U M E 8 , D O C U M E N T 2 8 2 a
The sonata goes like this: They are
We are already looking forward to Christmas and are curious what the Christ-
kindel is bringing us.
Christmas greetings from
Adn and Tete!
Vol. 8, 282a. To Ejnar Hertzsprung
[Berlin,] 5 December 1916
I certainly am used to the sky not being the limit! You are right, of course, with
, likewise with the relatively strong influence of the density. This is even
more unfortunate since density is only rarely obtainable and probably also quite un-
certain as well. Besides, the magnitude that results from occultations is not the den-
sity but the radius, so the effect vis-à-vis the observation[s] is better defined by
mass/radius than by the above formulation.
From among the points you touched upon, I will just address the last two be-
cause they relate to actual physics (not stellar observation).
An evaluation of the eccentricity of the Earth’s orbit without an extraterrestrial
light source is impossible, in principle, because according to the theory only the
frequency depends on the gravitational potential, not the wavelength measured
with a meter-stick.
An evaluation of the differences of gravitational potential on Earth would be
splendid, but these effects are fabulously tiny. If is the gravitational acceleration,
h the difference in altitude, then the Doppler velocity equivalent to this is:
= h/c(c = velocity of light).
For 3000 m that makes an altitudinal difference of
= 1/10 millimeter/second.
I don’t believe the thing about the Bunsen-burner flame, either. If the molecules
generating the luminescence have a thermal velocity of something like at least 100
m/sec, then such tiny relative velocities of the flames cannot yield such a huge ef-
fect as to be visible to the naked eye. In any event, one ought to get to the bottom