496 APPENDICESan excellent popular biography of Einstein [H4] and, together with Helen Dukas,
of a book on memorable pronouncements by Einstein [D3].*- Peter Gabriel Bergmann. b. 1915, Berlin. PhD in 1936 in Prague with
Philipp Frank, who recommended him to Einstein. Bergmann worked with Ein-
stein from 1936 to 1941. They published two joint papers on the five-dimensional
unification of electromagnetism and gravitation (Kaluza-Klein theory), the second
one in collaboration with Bargmann [E63, E64]. Einstein wrote an introduction
to Bergmann's textbook on relativity [E65]. Since 1950, Bergmann has held a
professorate at Syracuse University. - Valentin Bargmann. b. 1908, Berlin, of Russian parents. PhD in 1936
with Gregor Wentzel in Zurich. German citizen from 1925 until deprived of Ger-
man citizenship in 1934. Member of The Institute for Advanced Study 1937-46.
Bargmann and Einstein published two papers together, the one with Bergmann
just mentioned [E64] and a paper on bivectors [E66].** [Bivectors are quantities
Tlir(x^x 2 ), depending on a pair of space-time points, transforming under general
coordinate transformations like the product All(xi)B,(x 2 ), where Au(xt) and B,(x 2 )
are ordinary 4-vector fields.] Bargmann became professor at the University of
Pittsburg and, afterwards, professor of mathematical physics at Princeton Uni-
versity. - Wolfgang Fault, b. 1900, Vienna. PhD in 1921 with Sommerfeld in
Munich. Einstein wrote a laudatory review [E68] of Pauli's review article [P2]
on relativity theory. Pauli spent the years 1940-6 at The Institute for Advanced
Study in order to escape the menaces of war. In 1943 he wrote a joint paper with
Einstein [E69] in which it was proved that any everywhere regular and static
solution of the source-free gravitational equations which behaves at large distances
like a Schwarzschild solution must have a vanishing Schwarzschild mass. (A sim-
ilar theorem was shown to hold in the Kaluza-Klein theory.)!
It will be obvious that this brief comment is not in any way meant to do justice
to Pauli's contributions and influence in regard to relativity theory and relativistic
quantum theory. For a survey of Pauli's oeuvre, see [E71]. d. 1958, Zurich. - Ernst Gabor Straus, b. 1922, Munich. Assistant to Einstein 1944-8. At
the time Straus came to work with Einstein, the latter was much interested in the
problem of finding generalizations of general relativity that are not based on dif-
ferential geometry. He also discussed these matters with Pauli at that time. Two
examples of such generalizations (about which Einstein never published) are
found in Straus's reminiscences [Wl]. A joint paper on the influence of the expan-
sion of space on the gravitational fields surrounding individual stars was written
"The reader is urged to read the reminiscences of Hoffmann, Bargmann, Bergmann, and Straus in
[Wl].
"Einstein also wrote a sequel to this paper [E67].fThis is an improved version of an earlier result obtained by Einstein alone [E70].