Tibor Gallai

Hungarian mathematician (1912–1992)

Tibor Gallai
Born	(1912-07-15)15 July 1912 Budapest, Hungary
Died	2 January 1992(1992-01-02) (aged 79) Budapest, Hungary
Nationality	Hungarian
Alma mater	Technical University of Budapest
Known for	Sylvester–Gallai theorem
Scientific career
Fields	Mathematics
Institutions	Eötvös Loránd University
Doctoral advisor	Dénes Kőnig
Doctoral students	László Lovász

Tibor Gallai (born Tibor Grünwald, 15 July 1912 – 2 January 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 Kőnig and an advisor of László Lovász. He was a corresponding member of the Hungarian Academy of Sciences (1991).

His main results

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, 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 necessary and sufficient condition for a sequence to be the degree sequence of a graph, known as the Erdős–Gallai theorem.