ON PLANARITY OF GRAPHS ON WEYL GROUPS
Keywords:Weyl groups, root system, planarity of a graph
A graph is constructed whose vertices are elements of a Weyl group and the edges are defined through nonvanishing of Wey!'s dimension polynomial at the point associated with two elements of the Weyl group. We study the planarity of such graphs on Weyl groups whose associated root system is irreducible. These graphs include four families of infinite number of graphs. We show that very few graphs, essentially five of them, are planar.
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Samy A. Youssef, Ph. D. Thesis, Indian Istitute of Technology, Kharagpur, July 1993.
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