Algorithms for Twisted Involutions in Weyl Groups
نویسنده
چکیده
Let (W,Σ) be a finite Coxeter system, and θ an involution such that θ(∆) = ∆, where ∆ is a basis for the root system Φ associated with W , and Iθ = {w ∈ W | θ(w) = w−1} the set of θ-twisted involutions in W . The elements of Iθ can be characterized by sequences in Σ which induce an ordering called the Bruhat poset. The main algorithm of this paper computes this poset. Algorithms for finding conjugacy classes the closure of an element and special cases are also given. A basic analysis of the complexity of the main algorithm and its variations is discussed, as well experience with implementation.
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تاریخ انتشار 2006