Eamonn O'Brien (mathematician)

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Eamonn O'Brien
Eamonn O'Brien receiving Hector Medal 01 (cropped).jpg
O'Brien receiving the Hector Medal in 2020
Born
Eamonn Anthony O'Brien
Alma mater Australian National University
Known for
  • Computational group theory
  • Ore conjecture
Awards
Scientific career
Fields Mathematician
Institutions University of Auckland
Thesis The Groups of Order Dividing 256  (1988)
Doctoral advisor Michael F. Newman

Eamonn Anthony O'Brien FRSNZ is a professor of mathematics at the University of Auckland, New Zealand, known for his work in computational group theory and p-groups.

Contents

Education

O'Brien obtained his B.Sc. (Hons) from the National University of Ireland (Galway) in 1983. He completed his Ph.D. in 1988 at the Australian National University. His dissertation, The Groups of Order Dividing 256, was supervised by Michael F. Newman. [1]

Research

O'Brien's early work concerned classification, up to isomorphism, of groups of order 256. [2] He developed early computer software to complete the classification, and to verify that the classification can correct errors in earlier counting. This led to classifications of many further families of small order groups. In 2000, together with Bettina Eick and Hans Ulrich Besche, O'Brien classified all groups of order at most 2000, excluding those of order 1024. The groups of order 1024 were instead enumerated. [3] This classification is known as the Small Groups Library. Later with Michael F. Newman and Michael Vaughan-Lee O'Brien extended the classifications of groups of order , , and . These classifications comprise the tables provided in the computer algebra systems SageMath, GAP, and Magma.

For a 20-year span from the mid-1990s, O'Brien led the so-called Matrix Group Recognition Project whose primary objective is to solve the following problem: given a list of invertible matrices over a finite field, determine the composition series of the group. [4] [5] Implementations of algorithms that realize the goals of this project form the bedrock of matrix group computations in the computer algebra system Magma.

O'Brien's collaborations include resolution of several conjectures include the Ore conjecture, according to which all elements of non-abelian finite simple groups are commutators. [6]

Awards

Selected publications

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References

  1. Eamonn O'Brien at the Mathematics Genealogy Project
  2. O'Brien, E. A. (1991), "The groups of order 256", Journal of Algebra, 143 (1): 219–235, doi: 10.1016/0021-8693(91)90261-6 , MR   1128656
  3. Besche, Hans Ulrich; Eick, Bettina; O'Brien, E. A. (2002), "A millennium project: constructing small groups" (PDF), International Journal of Algebra and Computation, 12 (5): 623–644, doi:10.1142/S0218196702001115, MR   1935567
  4. 2014 BIRS Workshop: Algorithms for Linear Groups. Organizers Jon F. Carlson, Bettina Eick, Alexander Hulpke, Eamonn O’Brien.
  5. 2011 MFO Workshop: Computational Group Theory. Organizers: Bettina Eick, Gerhard Hiss, Derek Holt, Eamonn O'Brien.
  6. Malle, Gunter (2014), "The proof of Ore's conjecture (after Ellers-Gordeev and Liebeck-O'Brien-Shalev-Tiep)" (PDF), Astérisque (361): Exp. No. 1069, ix, 325–348, ISBN   978-285629-785-8, MR   3289286
  7. Royal Society of New Zealand
  8. Royal Society of New Zealand Members
  9. New Zealand Mathematics Research Awards
  10. Alexander von Humboldt Foundation