Kalle Väisälä

Kalle Väisälä , until 1906 Kalle Weisell , (born August 19, 1893 in Kontiolahti , Finland , † September 16, 1968 in Helsinki ) was a Finnish mathematician and teacher .

He was born as the youngest of eight children of Johannes Weisell, an employee of a sawmill in Utra (now part of Joensuu ), and Emma Birgitta Jääskeläinen. The father died in 1904, and the mother, who adopted the Finnish spelling of the family name in 1906, raised the five children who were still underage alone. Nevertheless, the three youngest, Vilho , Yrjö and Kalle, were able to attend university and pursue an academic career.

Kalle Väisälä studied mathematics at the University of Helsinki . He received his doctorate in 1916 under Ernst Lindelöf with the thesis "On the algebraically solvable equations of the fifth degree" . In 1919 he became professor of mathematics at the University of Dorpat (Tartu), in 1921 at the University of Turku and in 1938 in Helsinki at the University and the Technical University .

Väisälä wrote a number of mathematical textbooks, mainly on algebra and geometry , which reached a total of 800,000 copies.

The asteroid Kalle is named after him.

Fonts (selection)

• Generalization of the concept of the Dirichlet series , Mattiesen, Dorpat 1921
• New proof of the fundamental theorem about the algebraic solvability of equations whose degree is a composite number , Suomalainen Tiedeakatemia, Helsinki 1926

Web links

• Short biography on PlanethMath