Nilpotent Orbits and Commutative Elements
نویسنده
چکیده
Let W be a simply-laced Coxeter group with generating set S, and let Wc denote the subset consisting of those elements whose reduced expressions have no substrings of the form sts for any non-commuting s; t 2 S. We give a root system characterization of Wc, and in the case where W corresponds to a nite Weyl group, show that Wc is a union of Spaltenstein-Springer-Steinberg cells. The latter is valid also for aane Weyl groups of type A, but not for types D or E.
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تاریخ انتشار 1996