Lothar Collatz
Lothar Collatz | |
|---|---|
Lothar Collatz (Photo courtesy MFO) | |
| Born | July 6, 1910 |
| Died | September 26, 1990 (aged 80) |
| Nationality | German |
| Education | University of Greifswald University of Berlin |
| Known for | Collatz conjecture Collatz–Wielandt formula Spectral graph theory |
| Scientific career | |
| Fields | Mathematics |
| Institutions | University of Berlin Technische Hochschule Karlsruhe Technische Universität Darmstadt Technische Hochschule Hannover University of Hamburg |
| Doctoral advisor | Alfred Klose Erhard Schmidt |
| Doctoral students | Frank Natterer Heinz Unger |
Lothar Collatz (German: [ˈkɔlaʦ]; July 6, 1910 – September 26, 1990) was a German mathematician, born in Arnsberg, Westphalia.
The "3x + 1" problem is also known as the Collatz conjecture, named after him and still unsolved. The Collatz–Wielandt formula for the Perron–Frobenius eigenvalue of a positive square matrix was also named after him.
Collatz's 1957 paper with Ulrich Sinogowitz, who had been killed in the bombing of Darmstadt in World War II, founded the field of spectral graph theory.