Sibe Mardešić (June 20, 1927 - June 18, 2016) was a

Croatia Croatia, officially the Republic of Croatia, is a country in Central Europe, Central and Southeast Europe, on the coast of the Adriatic Sea. It borders Slovenia to the northwest, Hungary to the northeast, Serbia to the east, Bosnia and Herze ...

n mathematician.

Life and education

Sibe Mardešić was born in June 1927, in

Bergedorf Bergedorf () is the largest of the seven boroughs of Hamburg, Germany, named after Bergedorf quarter within this borough. In 2020 the population of the borough was 130,994. History The city of Bergedorf received town privileges in 1275, then ...

(near

Hamburg Hamburg (, ; ), officially the Free and Hanseatic City of Hamburg,. is the List of cities in Germany by population, second-largest city in Germany after Berlin and List of cities in the European Union by population within city limits, 7th-lar ...

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

), where his parents temporarily resided before moving to

Chile Chile, officially the Republic of Chile, is a country in western South America. It is the southernmost country in the world and the closest to Antarctica, stretching along a narrow strip of land between the Andes, Andes Mountains and the Paci ...

. After that, they returned to

Split Split(s) or The Split may refer to: Places * Split, Croatia, the largest coastal city in Croatia * Split Island, Canada, an island in the Hudson Bay * Split Island, Falkland Islands * Split Island, Fiji, better known as Hạfliua Arts, enter ...

, where he completed elementary school and high school. Soon after

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

he went to

Zagreb Zagreb ( ) is the capital (political), capital and List of cities and towns in Croatia#List of cities and towns, largest city of Croatia. It is in the Northern Croatia, north of the country, along the Sava river, at the southern slopes of the ...

to study

mathematics Mathematics is a field of study that discovers and organizes methods, Mathematical theory, theories and theorems that are developed and Mathematical proof, proved for the needs of empirical sciences and mathematics itself. There are many ar ...

. After graduation he took a job as an assistant at the Department of Mathematics of the

University of Zagreb The University of Zagreb (, ) is a public university, public research university in Zagreb, Croatia. It is the largest Croatian university and one of the oldest continuously operating universities in Europe. The University of Zagreb and the Unive ...

, where he stayed until his retirement in 1991. He was a full member of the Croatian Academy of Arts and Sciences, a corresponding member of the

Slovenian Academy of Sciences and Arts The Slovenian Academy of Sciences and Arts ( (SAZU)) is the national academy of Slovenia, which encompasses science and the arts and brings together the top Slovene researchers and artists as members of the academy. Cultural significance Establis ...

and a Fellow of the

American Mathematical Society The American Mathematical Society (AMS) is an association of professional mathematicians dedicated to the interests of mathematical research and scholarship, and serves the national and international community through its publications, meetings, ...

Work

Mardešić was a topologist who worked in all main branches of

topology Topology (from the Greek language, Greek words , and ) is the branch of mathematics concerned with the properties of a Mathematical object, geometric object that are preserved under Continuous function, continuous Deformation theory, deformat ...

having published 148 research papers, 40 professional articles and 18 books. With Jack Segal, he developed an alternate approach to shape theory using inverse systems method of ANRs generalizing Borsuk's shape theory to include all

compact Compact as used in politics may refer broadly to a pact or treaty; in more specific cases it may refer to: * Interstate compact, a type of agreement used by U.S. states * Blood compact, an ancient ritual of the Philippines * Compact government, a t ...

Hausdorff space In topology and related branches of mathematics, a Hausdorff space ( , ), T2 space or separated space, is a topological space where distinct points have disjoint neighbourhoods. Of the many separation axioms that can be imposed on a topologi ...

s, independently of Tim Porter and Włodzimierz Holsztyński. Later he extended Holsztyński's theory for compact Hausdorff spaces to all

topological space In mathematics, a topological space is, roughly speaking, a Geometry, geometrical space in which Closeness (mathematics), closeness is defined but cannot necessarily be measured by a numeric Distance (mathematics), distance. More specifically, a to ...

s. He introduced the first factorization theorem in

dimension theory In physics and mathematics, the dimension of a mathematical space (or object) is informally defined as the minimum number of coordinates needed to specify any point within it. Thus, a line has a dimension of one (1D) because only one coord ...

, the Mardešić factorization theorem. With P. Papić he introduced the notion of feebly compact spaces. He died on June 18, 2016, in Zagreb.

References

Selected publications

* * * * * * * S. Mardesic (1978). "Shape theory". Proceedings of the

International Congress of Mathematicians The International Congress of Mathematicians (ICM) is the largest conference for the topic of mathematics. It meets once every four years, hosted by the International Mathematical Union (IMU). The Fields Medals, the IMU Abacus Medal (known before ...

. * S. Mardesic; J. Segal (1982). "Shape theory". Elsevier. {{DEFAULTSORT:Mardesic, Sibe 1927 births 2016 deaths Yugoslav mathematicians Faculty of Science, University of Zagreb alumni Members of the Croatian Academy of Sciences and Arts Fellows of the American Mathematical Society Topologists 20th-century Croatian mathematicians