| Tibor Gallai | |
|---|---|
| Born | July 15, 1912 Budapest |
| Died | January 2, 1992 (aged 79) Budapest |
| Nationality | Hungary |
| Fields | Mathematics |
| Institutions | Eötvös Loránd University |
| Alma mater | Technical University of Budapest |
| Doctoral advisor | Dénes König |
| Doctoral students | Jenő Lehel László Lovász |
| Known for | Sylvester–Gallai theorem |
Tibor Gallai (born Tibor Grünwald, July 15, 1912 – January 2, 1992) was a Hungarian mathematician. He worked in combinatorics, especially in graph theory, and was a lifelong friend and collaborator of Paul Erdős. He was a student of Dénes König and an advisor of László Lovász. He was a corresponding member of the Hungarian Academy of Sciences (1991).
The Edmonds–Gallai decomposition theorem, which was proved independently by Gallai and Jack Edmonds, describes finite graphs from the point of view of matchings. Gallai also proved, with Milgram the Dilworth's theorem in 1947, but as they hesitated to publish the result, Dilworth independently discovered and published it.[1]
Gallai was the first to prove the higher dimensional version of van der Waerden's theorem.
With Paul Erdős he gave a sufficient and necessary condition for a sequence to be the degree sequence of a graph.