Dubbio sul motivo storico delle definizioni legate all'ordine e alla topologia

Testo nascosto, perché contrassegnato dall'autore come fuori tema. Fai click in quest'area per vederlo.

Banach è uno dei più grandi matematici del '900. Ma qui lo dico perché la sua biografia è un esempio degli orrori perpretati dal nazismo, anche nei confronti dei matematici. Non so se sapete come Banach dovette procurarsi da vivere dopo l'invasione nazista della Polonia, non potendo più insegnare. Non lo scrivo qui perché mi fa orrore solo scriverlo...

Banach ha anche una storia familiare "nebulosa"...

Testo nascosto, perché contrassegnato dall'autore come fuori tema. Fai click in quest'area per vederlo.

Cito da Pietsch, History of Banach Spaces and Linear Operators, pp. 638-639:

8.3.3.1 Stefan Banach was born in Krakow on March 30, 1892. His parents, Stefan Greczek and Katarzyna Banach, were not married. It is said that Banach spent some years of his childhood under the wings of his grandmother in Ostrowsko, the birthplace of his father. However, he was mainly brought up in Krakow by a foster-mother, Franziszka Płowa.

After the matura in 1910, Banach enrolled at the Faculty of Engineering of the Polytechnical Institute in Lwow. Due to the outbreak of World War I, he was not able to finish his studies.

A well-known story spread among mathematicians says that sometime in 1916, Steinhaus (then assistant at the University of Lwow) walked through a park in Krakow. Suddenly, he overheard the words Lebesgue integral; the youngsters who were discussing this unusual matter were Stefan Banach and Otton Nikodym; see [...]. This encounter was the beginning of a lifelong collaboration and the big bang of the famous Lwow school. Steinhaus always claimed that Banach was his greatest mathematical discovery.

In 1920, Banach became an assistant of A. Łomnicki (1881–1941) at the Lwow Polytechnical Institute. This was his first paid academic job. In June of the same year, he submitted his thesis Sur les operations dans les ensembles abstraits et leur application aux equations integrales at the Jan Kazimierz University. His habilitation followed in April 1922, and subsequently, in July 1922, he was appointed professor extraordinarius.

Banach stayed in Lwow throughout the rest of his life. During the Soviet occupation from September 1939 to June 1941 he was made dean of the PhysicalMathematical Faculty and head of the Department of Mathematical Analysis. Most horrible was the period from June 1941 to July 1944. Banach survived the Nazi pogrom thanks to the fact that he had an identity card as an employee of the Rudolf Weigl Bacteriological Institute. However, his job was embarrassing. He had to carry lice in a box that was placed on the back of his hands. These lice were used for producing anti-typhoid vaccines; additional information can be found in Alexander’s review [...].

After the end of the war, Banach immediately resumed his academic duties. However, all of his plans for the future were stopped by a serious illness, lung cancer. Banach died in Lwow on August 31, 1945. Pictures of Banach’s grave can be found in an article of Ciesielski [...].

8.3.3.2 A mysterious story about the origin of Stefan Banach reads as follows:

In Tel Aviv, V. Milman [...] met an old lady whose maiden name was Banach. She told him that her grandmother (Netl Banach married to a cousin, by the name of Moshe Banach) had a younger brother who became a famous mathematician in Lwow. Since the boy did not like to live according to the orthodox Jewish tradition, he went away at the age of about fifteen and converted to catholicism.
As a consequence, nobody from his former family was allowed to remember this black sheep, and therefore no further information is available.

@ mklplo: Il testo di Banach è importante perché, detto in maniera semplice, lì è nata l'Analisi Funzionale.

Grazie di nuovo per aver risposto,è sempre bello scoprire qualche cosa di nuovo.