Gerard Laman

Gerard Laman (August 22, 1924 – September 22, 2009) was a Dutch mathematician who worked on graph theory.

Gerard Laman.

Early life

He completed high school studies at the Stedelijk Gymnasium Leiden in 1942. His study of Mathematics at Leiden University was delayed by a period in hiding to evade enforced labor during the Nazi occupation of the Netherlands. He completed a degree in Mathematics with a minor in Mechanics in 1952. From 1949 onwards, he was a scientific assistant to J. Haantjes.

He received private instruction in the combinatorial topology of fiber spaces in Brussels from G. Hirsch of the Agricultural University of Ghent in 1953. During this period he received a stipend from the Dutch-Belgian Cultural Accord.

From 1954 to 1957 he taught mathematics at the Delft high school 'Gemeentelijke Hogere Burgerschool HBS'.

In 1959 he completed his PhD thesis[1] at Leiden University. W. T. van Est acted as his supervisor, once the original supervisor J. Haantjes was deceased.

Career

From 1957 to 1967 he worked as a lecturer at the 'Technische Hogeschool' of Eindhoven (now Eindhoven University of Technology).

From 1967 to his retirement in 1989, he worked as a lecturer at the Mathematical Institute of the University of Amsterdam, teaching discrete mathematics and mathematics for students in Econometrics. Laman regarded himself mostly as a teacher. Clear thinking, as well as brevity in speech and writing, were his forte.

Laman is often credited with proving, in 1970,[2] that a particular family of sparse graphs, since named Laman graphs, are precisely those that are minimally generically rigid in the plane. This result, however, had already been proven by Hilda Geiringer back in 1927.[3]

Laman's original publication in 1970 went largely unnoticed at first. Only when Branko Grünbaum and G. C. Shephard wrote about Laman's paper in their Lectures on lost mathematics[4] did this work receive more attention.

Towards the end of his life, Laman worked to lift the original 'Laman graph' from its original two dimensions to three, inspired by a simple counterexample, the 'double banana graph'.[5]

Notes
  1. Laman 1959.
  2. Laman 1970.
  3. Pollaczek‐Geiringer, Hilda (1927), "Über die Gliederung ebener Fachwerke", Zeitschrift für Angewandte Mathematik und Mechanik, 7 (1): 58–72.
  4. Grünbaum & Shephard 1978.
  5. Graver, Servatius & Servatius 1993, p. 12.

References
  • Graver, J.; Servatius, B.; Servatius, H. (1993), Combinatorial rigidity, Graduate Studies in Mathematics, 2, American Mathematical Society, Providence, RI, MR 1251062CS1 maint: ref=harv (link)
  • Grünbaum, B.; Shephard, G.C. (1978), Lectures on lost mathematics, Lecture Notes, Univ. of WashingtonCS1 maint: ref=harv (link)
  • Laman, G. (1959), On automorphisms of transformationgroups of polynomial algebras, Thesis, Rijksuniversiteit Leiden, MR 0108508CS1 maint: ref=harv (link)
  • Laman, G. (1970), "On graphs and rigidity of plane skeletal structures", J. Engrg. Math., 4 (4): 331–340, doi:10.1007/BF01534980, MR 0269535CS1 maint: ref=harv (link)
  • Owen, J.C.; Power, S.C. (2007), "The non-solvability by radicals of generic 3-connected planar Laman graphs", Trans. Amer. Math. Soc., 359 (5): 2269–2303, doi:10.1090/S0002-9947-06-04049-9, MR 2276620CS1 maint: ref=harv (link)
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