Nachman Aronszajn (26 July 1907 – 5 February 1980) was a
Polish American mathematician. Aronszajn's main field of study was
mathematical analysis, where he systematically developed the concept of
reproducing kernel Hilbert space. He also contributed to
mathematical logic.
Life
An
Ashkenazi Jew
Ashkenazi Jews ( ; he, יְהוּדֵי אַשְׁכְּנַז, translit=Yehudei Ashkenaz, ; yi, אַשכּנזישע ייִדן, Ashkenazishe Yidn), also known as Ashkenazic Jews or ''Ashkenazim'',, Ashkenazi Hebrew pronunciation: , singu ...
, Aronszajn received his Ph.D. from the
University of Warsaw, in 1930, in
Poland.
Stefan Mazurkiewicz
Stefan Mazurkiewicz (25 September 1888 – 19 June 1945) was a Polish mathematician who worked in mathematical analysis, topology, and probability. He was a student of Wacław Sierpiński and a member of the Polish Academy of Learning (''PAU''). ...
was his thesis advisor. He also received a Ph.D. from
Paris University, in 1935; this time
Maurice Fréchet Maurice may refer to:
People
*Saint Maurice (died 287), Roman legionary and Christian martyr
*Maurice (emperor) or Flavius Mauricius Tiberius Augustus (539–602), Byzantine emperor
*Maurice (bishop of London) (died 1107), Lord Chancellor and Lo ...
was his thesis advisor. He joined the
Oklahoma State University faculty, but moved to the
University of Kansas in 1951 with his colleague
Ainsley Diamond
Ainsley (also spelt Ainsleigh) is both a unisex given name and a surname and place name. It is derived from words meaning hermitage and clearing.
Notable people with the name include:
Given name Men
*Ainsley Battles (born 1978), American fo ...
after Diamond, a
Quaker
Quakers are people who belong to a historically Protestant Christian set of Christian denomination, denominations known formally as the Religious Society of Friends. Members of these movements ("theFriends") are generally united by a belie ...
, was fired for refusing to sign a newly instituted loyalty oath.
[.] Aronszajn retired in 1977. He was a Summerfield Distinguished Scholar from 1964 to his death.
Work
He introduced, together with
Prom Panitchpakdi
A promenade dance, commonly called a prom, is a dance party for high school students. It may be offered in semi-formal black tie or informal suit for boys, and evening gowns for girls. This event is typically held near the end of the school year ...
,
injective metric spaces under the name of "hyperconvex metric spaces". Together with Kennan T. Smith, Aronszajn offered proof of the
Aronszajn–Smith theorem. Also, the existence of
Aronszajn trees In set theory, an Aronszajn tree is a tree of uncountable height with no uncountable branches and no uncountable levels. For example, every Suslin tree is an Aronszajn tree. More generally, for a cardinal ''κ'', a ''κ''-Aronszajn tree is a tree of ...
was proven by Aronszajn;
Aronszajn line In mathematical set theory, an Aronszajn line (named after Nachman Aronszajn) is a linear ordering of cardinality \aleph_1
which contains no subset order-isomorphic to
* \omega_1 with the usual ordering
* the reverse of \omega_1
* an uncountable s ...
s, also named after him, are the
lexicographic ordering
In mathematics, the lexicographic or lexicographical order (also known as lexical order, or dictionary order) is a generalization of the alphabetical order of the dictionaries to sequences of ordered symbols or, more generally, of elements of ...
s of Aronszajn trees.
He also made a contribution to the theory of
reproducing kernel Hilbert space. The
Moore–Aronszajn theorem is named after him.
References
External links
Nachman Aronszajn on Scientific Commons
– personal papers of Nachman Aronszajn, 1951–1977
*
{{DEFAULTSORT:Aronszajn, Nachman
1907 births
1980 deaths
American people of Polish-Jewish descent
Mathematical analysts
Polish emigrants to the United States
Warsaw School of Mathematics
20th-century American mathematicians
University of Kansas faculty
Oklahoma State University faculty
University of Warsaw alumni
People from Warsaw
University of Paris alumni