Nachman Aronszajn

Nachman Aronszajn
Born	1907 Poland
Died	1980 United States
Nationality	Polish American
Fields	Mathematics
Institutions	University of Kansas
Alma mater	University of Warsaw University of Paris
Doctoral advisor	Maurice René Fréchet Stefan Mazurkiewicz
Doctoral students	W. Martin Greenlee
Known for	Aronszajn line Aronszajn–Smith theorem Aronszajn trees Moore–Aronszajn theorem

Nachman Aronszajn (1907–1980) was a Polish American mathematician of Jewish descent. Aronszajn's main field of study and expertise was mathematical analysis. He also contributed to mathematical logic.

Life

He received his Ph.D. from the University of Warsaw, in 1930, in Poland. Stefan Mazurkiewicz was his thesis advisor. He also received a Ph.D. from Paris University, in 1935; this time Maurice Fréchet was his thesis advisor. He joined the Oklahoma A&M faculty, but moved to the University of Kansas in 1951 with his colleague Ainsley Diamond after Diamond, a quaker, was fired for refusing to sign a newly-instituted loyalty oath.^[1] Aronszajn retired in 1977. He was a Summerfield Distinguished Scholar from 1964 to his death.

Work

He introduced, together with Prom Panitchpakdi, the 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 was proven by Aronszajn; Aronszajn lines, also named after him, are the lexicographic orderings of Aronszajn trees.

He also has a fundamental contribution to the theory of reproducing kernel Hilbert space, the Moore–Aronszajn theorem is named after him.^[2]

References

1. ^ Magill, K. D., Jr. (1996), "An interview with John Isbell", Topology Communications 1 (2), http://at.yorku.ca/t/o/p/c/06.htm .
2. ^ Aronszajn, Nachman (1950). "Theory of Reproducing Kernels". Transactions of the American Mathematical Society 68 (3): 337–404. 

External links

• Nachman Aronszajn on Scientific Commons.
• Guide to the Nachman Aronszajn Collection – personal papers of Nachman Aronszajn, 1951–1977
• Nachman Aronszajn at the Mathematics Genealogy Project.

Persondata
Name	Aronszajn, Nachman
Alternative names
Short description	Mathematician
Date of birth	1907
Place of birth	Poland
Date of death	1980
Place of death	United States