D O C U M E N T 4 2 1 J A N U A R Y 1 9 2 5 4 1 3
is immobile. Is it worth the effort to insist on this relative character of radiation?
And do you think it useful to overcome my repugnance to publish in order to offer
the quite expansive work I did on this topic, connected with the question of know-
ing whether an immobile charged particle in a static gravitational field radiates or
does not radiate?
I transmitted the praiseworthy assessment to Mr. Louis de Broglie that you gave
me about his
—he will certainly appreciate it very much. At the time of the
defense of his thesis, I examined quite closely his ideas, to which I am going to
come back during my course—quite some difficulties still remain—but I have the
impression I gave you in Geneva, and which you confirmed to me, that we must see
how far one can go in this direction.
I would like to chat with you about this and many other things as well. A meeting
of the Committee on [Intellectual] Cooperation in Paris
I believe, being
planned. Can we hope to see you there? That would be delightful.
My son Jean, whom you
has been in Egypt since last October, where
he accepted a post for one year at the secondary school in Alexandria. He is en-
chanted with what he sees, having already been able to travel a little to Cairo and
Upper Egypt, to Luxor, Assuan, etc., whither I would have liked to be able to ac-
All of us extend to you, as well as to Mrs. Einstein, our best wishes for the new
year, during the course of which nothing would be more agreeable and comforting
than to be able to meet you a little more often. Let it also bring us comfort from the
general point of view. That depends essentially on the relations between our two
countries. The conditions for this are excellent here, where good policy is affirming
itself more and more; and what you tell me also gives me reason to hope.
An affectionate embrace,
421. From Auguste Piccard
Brussels, 14 Ernestine Ave., 13 January 1924
Highly esteemed Professor,
Your kind letter of the 28th of Dec. pleased me very
I am thus going to
work with expansion in the indicated way, which should at all events yield an in-
Because the result will probably be negative, I am already occupying myself
now with another problem that I would like to submit to your judgment. It can very