Ernst Leonard Lindelöf
Encyclopedia
Ernst Leonard Lindelöf, (7 March 1870, Helsinki
(in Swedish: Helsingfors)–4 June 1946, Helsinki) was a Finnish
topologist
after whom Lindelöf spaces
are named; he was the son of Leonard Lorenz Lindelöf and brother of the philologist Uno Lorenz Lindelöf.
Lindelöf studied at the University of Helsinki
, where he completed his Ph.D.
in 1893, became a docent
in 1895 and professor
of Mathematics in 1903. He was a member of the Finnish Society of Sciences and Letters
.
In addition to working on mathematical topics as diverse as differential equation
s and the gamma function
, Lindelöf actively promoted the study of the history of Finnish mathematics.
Helsinki
Helsinki is the capital and largest city in Finland. It is in the region of Uusimaa, located in southern Finland, on the shore of the Gulf of Finland, an arm of the Baltic Sea. The population of the city of Helsinki is , making it by far the most populous municipality in Finland. Helsinki is...
(in Swedish: Helsingfors)–4 June 1946, Helsinki) was a Finnish
Finland
Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...
topologist
Topology
Topology is a major area of mathematics concerned with properties that are preserved under continuous deformations of objects, such as deformations that involve stretching, but no tearing or gluing...
after whom Lindelöf spaces
Lindelöf space
In mathematics, a Lindelöf space is a topological space in which every open cover has a countable subcover. The Lindelöf property is a weakening of the more commonly used notion of compactness, which requires the existence of a finite subcover....
are named; he was the son of Leonard Lorenz Lindelöf and brother of the philologist Uno Lorenz Lindelöf.
Lindelöf studied at the University of Helsinki
University of Helsinki
The University of Helsinki is a university located in Helsinki, Finland since 1829, but was founded in the city of Turku in 1640 as The Royal Academy of Turku, at that time part of the Swedish Empire. It is the oldest and largest university in Finland with the widest range of disciplines available...
, where he completed his Ph.D.
Ph.D.
A Ph.D. is a Doctor of Philosophy, an academic degree.Ph.D. may also refer to:* Ph.D. , a 1980s British group*Piled Higher and Deeper, a web comic strip*PhD: Phantasy Degree, a Korean comic series* PhD Docbook renderer, an XML renderer...
in 1893, became a docent
Docent
Docent is a title at some European universities to denote a specific academic appointment within a set structure of academic ranks below professor . Docent is also used at some universities generically for a person who has the right to teach...
in 1895 and professor
Professor
A professor is a scholarly teacher; the precise meaning of the term varies by country. Literally, professor derives from Latin as a "person who professes" being usually an expert in arts or sciences; a teacher of high rank...
of Mathematics in 1903. He was a member of the Finnish Society of Sciences and Letters
Finnish Society of Sciences and Letters
The Finnish Society of Sciences and Letters is a Finnish academy for natural sciences, social sciences and humanities. It is known in Latin as Societas Scientiarum Fennica, in Swedish as Finska Vetenskaps-Societeten, and in Finnish as Suomen Tiedeseura.The society was founded in 1838 and is based...
.
In addition to working on mathematical topics as diverse as differential equation
Differential equation
A differential equation is a mathematical equation for an unknown function of one or several variables that relates the values of the function itself and its derivatives of various orders...
s and the gamma function
Gamma function
In mathematics, the gamma function is an extension of the factorial function, with its argument shifted down by 1, to real and complex numbers...
, Lindelöf actively promoted the study of the history of Finnish mathematics.
See also
- Lindelöf hypothesis
- Lindelöf's lemmaLindelöf's lemmaIn mathematics, Lindelöf's lemma is a simple but useful lemma in topology on the real line, named for the Finnish mathematician Ernst Leonard Lindelöf.-Statement of the lemma:Let the real line have its standard topology...
- Lindelöf's theoremLindelöf's theoremIn mathematics, Lindelöf's theorem is a result in complex analysis named after the Finnish mathematician Ernst Leonard Lindelöf. It states that a holomorphic function on a half-strip in the complex plane that is bounded on the boundary of the strip and does not grow "too fast" in the unbounded...
- Phragmén–Lindelöf principle
- Picard–Lindelöf theoremPicard–Lindelöf theoremIn mathematics, in the study of differential equations, the Picard–Lindelöf theorem, Picard's existence theorem or Cauchy–Lipschitz theorem is an important theorem on existence and uniqueness of solutions to first-order equations with given initial conditions.The theorem is named after Charles...
Selected bibliography
- Le calcul des résidus et ses applications à la théorie des fonctions (Paris, 1905)
- Mémoire sur la théorie des fonctions entiéres d'ordre fini ("Acta societatis scientiarum fennicae" 31, 1903)
- With Lars Edvard PhragménLars Edvard PhragménLars Edvard Phragmén was a Swedish mathematician.The son of a college professor, he studied at Uppsala then Stockholm, graduating Uppsala in 1889. He became professor at Stockholm in 1892, after Sofia Kovalevskaia....
: "Sur une extension d'un principe classique de l'analyse et sur quelques propriétés des fonctions monogènes dans le voisinage d'un point singulier", in: Acta mathematicaActa MathematicaActa Mathematica is a journal publishing original research papers in all fields of mathematics. The journal was founded by Gösta Mittag-Leffler in 1882 and is published by Institut Mittag-Leffler, a research institute for mathematics belonging to the Royal Swedish Academy of Sciences...
31, 1908.