Robin Thomas (mathematician)

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Robin Thomas
Born(1962-08-22)August 22, 1962 [1]
Prague, Czechoslovakia
DiedMarch 26, 2020(2020-03-26) (aged 57) [2]
Alma mater Charles University
Awards Fulkerson Prize
Karel Janeček Foundation Neuron Prize
Scientific career
Fields Mathematics
Institutions Georgia Institute of Technology
Doctoral advisor Jaroslav Nešetřil

Robin Thomas (August 22, 1962 – March 26, 2020) was a mathematician working in graph theory at the Georgia Institute of Technology.


Thomas received his doctorate in 1985 from Charles University in Prague, Czechoslovakia (now the Czech Republic), under the supervision of Jaroslav Nešetřil. [3] He joined the faculty at Georgia Tech in 1989, and became a Regents' Professor there, [4] [5] briefly serving as the department Chair.

On March 26, 2020, he lost his twelve-year struggle against Amyotrophic Lateral Sclerosis at the age of 57. [2] [6]


Thomas was awarded the Fulkerson Prize for outstanding papers in discrete mathematics twice, [7] in 1994 as co-author of a paper on the Hadwiger conjecture, [8] and in 2009 for the proof of the strong perfect graph theorem. [9] In 2011 he was awarded the Karel Janeček Foundation Neuron Prize for Lifetime Achievement in Mathematics. [10] In 2012 he became a fellow of the American Mathematical Society. [11] He was named a SIAM Fellow in 2018. [12]

Related Research Articles

In graph theory, an undirected graph H is called a minor of the graph G if H can be formed from G by deleting edges and vertices and by contracting edges.

In graph theory, the perfect graph theorem of László Lovász states that an undirected graph is perfect if and only if its complement graph is also perfect. This result had been conjectured by Berge, and it is sometimes called the weak perfect graph theorem to distinguish it from the strong perfect graph theorem characterizing perfect graphs by their forbidden induced subgraphs.

Snark (graph theory)

In the mathematical field of graph theory, a snark is a simple, connected, bridgeless cubic graph with chromatic index equal to 4. In other words, it is a graph in which every vertex has three neighbors, the connectivity is redundant so that removing no one edge would split the graph, and the edges cannot be colored by only three colors without two edges of the same color meeting at a point. In order to avoid trivial cases, snarks are often restricted to have girth at least 5.

In graph theory, the strong perfect graph theorem is a forbidden graph characterization of the perfect graphs as being exactly the graphs that have neither odd holes nor odd antiholes. It was conjectured by Claude Berge in 1961. A proof by Maria Chudnovsky, Neil Robertson, Paul Seymour, and Robin Thomas was announced in 2002 and published by them in 2006.

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Hadwiger conjecture (graph theory)

In graph theory, the Hadwiger conjecture states that if G is loopless and has no minor then its chromatic number satisfies . It is known to be true for . The conjecture is a generalization of the four-color theorem and is considered to be one of the most important and challenging open problems in the field.

Hadwiger number

In graph theory, the Hadwiger number of an undirected graph G is the size of the largest complete graph that can be obtained by contracting edges of G. Equivalently, the Hadwiger number h(G) is the largest number k for which the complete graph Kk is a minor of G, a smaller graph obtained from G by edge contractions and vertex and edge deletions. The Hadwiger number is also known as the contraction clique number of G or the homomorphism degree of G. It is named after Hugo Hadwiger, who introduced it in 1943 in conjunction with the Hadwiger conjecture, which states that the Hadwiger number is always at least as large as the chromatic number of G.

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Apex graph

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Zdeněk Dvořák is a Czech mathematician specializing in graph theory.


  1. Cremation Society of Georgia: Robin Thomas
  2. 1 2 Fortnow, Lance (March 28, 2020). "Robin Thomas". Computational Complexity.
  3. Robin Thomas at the Mathematics Genealogy Project.
  4. Author biography from Berg, Deborah E.; Norine, Serguei; Su, Francis Edward; Thomas, Robin; Wollan, Paul. "Voting in agreeable societies". arXiv: 0811.3245 ..
  5. Robin Thomas Earns Distinction, Named Regents' Professor, Georgia Tech College of Computing, June 24, 2010.
  6. Robin Thomas tribute, Georgia Tech Mathematics, April 7, 2020.
  7. Fulkerson Prize: Official site with award details.
  8. Robertson, Neil; Seymour, Paul; Thomas, Robin (1993), "Hadwiger's conjecture for K6-free graphs", Combinatorica , 13 (3): 279–361, doi:10.1007/BF01202354 .
  9. Chudnovsky, Maria; Robertson, Neil; Seymour, Paul; Thomas, Robin (2006), "The strong perfect graph theorem", Annals of Mathematics , 164 (1): 51–229, arXiv: math/0212070 , doi:10.4007/annals.2006.164.51 .
  10. Karel Janeček Foundation 2011 Neuron Prize winners (in Czech) Archived 2012-12-23 at the Wayback Machine
  11. List of Fellows of the American Mathematical Society, retrieved 2013-08-27.
  12. "SIAM Announces Class of 2018 Fellows", SIAM News, March 29, 2018