D O C U M E N T 3 0 5 N O V E M B E R 1 9 2 1 1 9 1
and, if one also interprets
as time-like ( , as ), there is a real difference on the right-hand
side. The corresponding thing occurs in the equations of motions with .
So if the approximations were satisfied strictly, then that difference would exist
with and therefore every gravitational effect vanish, indeed for
any ! Thus one can set instead of such a large factor for the energy tensor that
despite the small (in order of magnitude 1) the electric effects come out in the
right order of magnitude anyway ( then becomes without bringing
with it overwhelming gravitational effects. The gravitation would then just remain
as a difference effect ( against This sounds very adventurous and is, of
course, still very immature. But I went along with this because the possibility of
understanding this atrociously small k, which as Weyl says “does not fit at all with-
in the framework of the rest of the natural constants,”[9] as a statistical quantity, as
a “left-over,” appears enticing. If the world ultimately was just composed of elec-
trons, this idea would perhaps be executable; but then the H-nuclei interfere with
their smaller . The asymmetry between the two electricities will probably
cause problems everywhere and, to my knowledge, it also does so with
Weyl.[10]
If you, highly esteemed Professor, are of the opinion that all this is still far too
much up in the air or definitely means a dead end, I shall be glad to strike the rele-
vant section for the time being. But it might also inspire someone, who has more
time and more propitious insight than I, to a better idea.–
In expressing my sincere thanks to you, esteemed Professor, for your renewed
generous interest, I am with most humble regards, respectfully yours,
Kaluza.
306. To David A. Lourie[1]
Berlin, 29 November 1921
[See the documentary edition for the original English.]
R00
2
- T00 T44 – –-- ~ –R44 ~
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2
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00 44
– ~
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dx0
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107),
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g00
g44).[8]
e
M
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104
~