Karol Borsuk

Infobox Scientist
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name = Karol Borsuk


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birth_date = birth date|1905|5|8
birth_place = Warsaw, Poland
death_date = death date and age|1982|1|24|1905|5|8
death_place = Warsaw, Poland
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nationality = POL
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fields = Mathematics
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alma_mater = Warsaw University
doctoral_advisor = Stefan Mazurkiewicz
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notable_students = Samuel Eilenberg
Krystyna Kuperberg
known_for = Borsuk's conjecture
Borsuk-Ulam theorem
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Karol Borsuk (May 8, 1905, Warsaw – January 24, 1982, Warsaw) was a Polish mathematician. His main interest was topology.

Borsuk introduced the theory of "absolute retracts" (ARs) and "absolute neighborhood retracts" (ANRs), and the cohomotopy groups, later called Borsuk-Spanier cohomotopy groups. He has constructed various beautiful examples of topological spaces, e.g. an acyclic, 3-dimensional continuum which admits a fixed point free homeomorphism onto itself; also 2-dimensional, contractible polyhedra which have no free edge. His topological and geometric conjectures and themes stimulated research for more than half a century.

Borsuk received his master's degree and doctorate from Warsaw University in 1927 and 1930, respectively; his Ph.D. thesis advisor was Stefan Mazurkiewicz. He was a member of the Polish Academy of Sciences from 1952. Borsuk's students included Samuel Eilenberg and Krystyna Kuperberg.

ee also

* Borsuk's conjecture
* Borsuk-Ulam theorem
* Zygmunt Janiszewski
* shape theory
* Stanislaw Ulam
* Scottish Café

Works

* "Geometria analityczna w n wymiarach" (1950)
* "Podstawy geometrii" (1955)
* "Foundations of Geometry" (1960) with Wanda Szmielew, North Holland publisher
* "Theory of Retracts" (1966)
* "Theory of Shape" (1975)

External links

*MacTutor Biography|id=Borsuk
*MathGenealogy |id=12548

Persondata
NAME= Borsuk, Karol
ALTERNATIVE NAMES=
SHORT DESCRIPTION=Polish mathematician
DATE OF BIRTH= 1905-5-8
PLACE OF BIRTH= Warsaw, Poland
DATE OF DEATH= 1982-1-24
PLACE OF DEATH= Warsaw, Poland