D O C U M E N T 1 6 3 N O V E M B E R 1 9 2 3 1 5 9
from [your] relations (or
I concluded that
It seems to me that there is a point in your exposition that I must have misunder-
stood quite badly. The few developments written above will, I hope, permit you to
fill this lacuna without difficulty.
I learned with pleasure that you intend to stay on for some time at Leyden. It
would be very useful for me to see you during the Christmas vacation, if possible.
Here is why. The Paris Faculty of Sciences gave me the honor of inviting me to hold
some talks (or lectures) at the Sorbonne. I have accepted and have taken as a topic:
The New Einsteinian Gravity.
It would, therefore, be indispensable that I be completely up to date on your lat-
est research; yet we do not receive here (in Belgium) the Sitzungsberichte from
Berlin in which your most recent research and discoveries appear.
It would also be useful for me to show you the program that I want to develop in
Paris, to ask your opinion.
May I ask until what date you will be staying in Leyden as well as the period in
which I could meet you there?
Most respectfully yours,
T. De Donder.
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il σul ≡