Involutions in Weyl group of type F4

Abstract

Let W be the Weyl group of type F₄: We explicitly describe a nite set of basic braid I_*-transformations and show that any two reduced I_*-expressions for a given involution in W can be transformed into each other through a series of basic braid I_*-transformations. Our main result extends the earlier work on the Weyl groups of classical types (i.e., A_n; B_n; and D_n).

Keywords

Involutions / reduced I_*-expressions / braid I_*-transformations

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Higher Education Press and Springer-Verlag Berlin Heidelberg