Neil Robertson (mathematician)

Last updated
Neil Robertson
BornNovember 30, 1938 (1938-11-30) (age 86)
Alma mater University of Waterloo,
Known for Robertson–Seymour theorem
Awards Pólya Prize (SIAM) (2004, 2006)
Scientific career
Fields Mathematician
Institutions Ohio State University
Thesis Graphs Minimal under Girth, Valency and Connectivity Constraints  (1969)
Doctoral advisor William Tutte
Doctoral students

George Neil Robertson (born November 30, 1938) is a mathematician working mainly in topological graph theory, currently a distinguished professor emeritus at the Ohio State University. [1] [2]

Contents

Education

Robertson earned his B.Sc. from Brandon College in 1959 and his Ph.D. in 1969 at the University of Waterloo under his doctoral advisor William Tutte. [3] [4]

Biography

In 1969, Robertson joined the faculty of the Ohio State University, where he was promoted to Associate Professor in 1972 and Professor in 1984. He was a consultant with Bell Communications Research from 1984 to 1996. He has held visiting faculty positions in many institutions, most extensively at Princeton University from 1996 to 2001, and at Victoria University of Wellington, New Zealand, in 2002. He also holds an adjunct position at King Abdulaziz University in Saudi Arabia. [2]

Research

Robertson is known for his work in graph theory, and particularly for a long series of papers co-authored with Paul Seymour and published over a span of many years, in which they proved the Robertson–Seymour theorem (formerly Wagner's Conjecture). [5] This states that families of graphs closed under the graph minor operation may be characterized by a finite set of forbidden minors. As part of this work, Robertson and Seymour also proved the graph structure theorem describing the graphs in these families. [6]

Additional major results in Robertson's research include the following:

Awards and honors

Robertson has won the Fulkerson Prize three times, in 1994 for his work on the Hadwiger conjecture, in 2006 for the Robertson–Seymour theorem, and in 2009 for his proof of the strong perfect graph theorem. [11]

He also won the Pólya Prize (SIAM) in 2004, the OSU Distinguished Scholar Award in 1997, and the Waterloo Alumni Achievement Medal in 2002. In 2012 he became a fellow of the American Mathematical Society. [12]

See also

Related Research Articles

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<span class="mw-page-title-main">Perfect graph</span> Graph with tight clique-coloring relation

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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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<span class="mw-page-title-main">Paul Seymour (mathematician)</span> British mathematician

Paul D. Seymour is a British mathematician known for his work in discrete mathematics, especially graph theory. He was responsible for important progress on regular matroids and totally unimodular matrices, the four colour theorem, linkless embeddings, graph minors and structure, the perfect graph conjecture, the Hadwiger conjecture, claw-free graphs, χ-boundedness, and the Erdős–Hajnal conjecture. Many of his recent papers are available from his website.

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References

  1. Neil Robertson awarded the title of Distinguished Professor, David Goss, Ohio State, 2006-09-26.
  2. 1 2 Bhattacharjee, Yudhijit (9 December 2011), "Saudi Universities offer cash in exchange for academic prestige", Science , 334 (6061): 1344–1345, Bibcode:2011Sci...334.1344B, doi:10.1126/science.334.6061.1344, PMID   22158799 .
  3. The Sickle, Brandon College Year Book 1959 p.30
  4. G. Neil (George) Robertson at the Mathematics Genealogy Project
  5. Robertson, Neil; Seymour, P. D. (2004-11-01). "Graph Minors. XX. Wagner's conjecture". Journal of Combinatorial Theory, Series B. Special Issue Dedicated to Professor W.T. Tutte. 92 (2): 325–357. doi: 10.1016/j.jctb.2004.08.001 . ISSN   0095-8956.
  6. Robertson, Neil; Seymour, P. D (2003-09-01). "Graph Minors. XVI. Excluding a non-planar graph". Journal of Combinatorial Theory, Series B. 89 (1): 43–76. doi:10.1016/S0095-8956(03)00042-X. ISSN   0095-8956.
  7. Robertson, Neil (1964). "The smallest graph of girth 5 and valency 4". Bulletin of the American Mathematical Society. 70 (6): 824–825. doi: 10.1090/S0002-9904-1964-11250-7 . ISSN   0273-0979.
  8. Robertson, Neil; Seymour, Paul; Thomas, Robin (1993-09-01). "Hadwiger's conjecture forK6-free graphs". Combinatorica. 13 (3): 279–361. doi:10.1007/BF01202354. ISSN   1439-6912.
  9. Robertson, Neil; Sanders, Daniel; Seymour, Paul; Thomas, Robin (1996). "A new proof of the four-colour theorem". Electronic Research Announcements of the American Mathematical Society. 2 (1): 17–25. doi:10.1090/S1079-6762-96-00003-0. ISSN   1079-6762.
  10. Chudnovsky, Maria; Robertson, Neil; Seymour, Paul; Thomas, Robin (2006-07-01). "The strong perfect graph theorem". Annals of Mathematics. 164 (1): 51–229. arXiv: math/0212070 . doi:10.4007/annals.2006.164.51. ISSN   0003-486X.
  11. Delbert Rey Fulkerson Prize, American Mathematical Society, accessed 2012-01-03.
  12. List of Fellows of the American Mathematical Society, retrieved 2013-07-07.