Centers of generic Hecke algebras
Centers of generic Hecke algebras
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DOI:
10.1090/s0002-9947-1990-0948191-6
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发表时间:
1990
影响因子:
1.3
通讯作者:
L. Jones
中科院分区:
文献类型:
--
作者:
L. Jones
Let W be a Weyl group and let W' be a parabolic subgroup of W. Define A as follows: A = R 0Q[u] (W) where X' (W) is the generic algebra of type A, over Q[u], u an indeterminate, associated with the group W, and R is a Q[u]-algebra, possibly of infinite rank, in which u is invertible. Similarly, we define A' associated with W' . Let M be an A-A bimodule, and let b E M. Define the relative norm [14] NW,W'(b) = Eul(t)at-,bat tET where T is the set of distinguished right coset representives for W' in W. We show that if b E ZM(A') = {m E Mlma' = a'm Va' E A'}, then Nw w (b) E ZM (A). In addition, other properties of the relative norm are given and used to develop a theory of induced modules for generic Hecke algebras including a Markey decomposition. This section of the paper is previously unpublished work of P. Hoefsmit and L. L. Scott. Let *e = (kl,k2,...,k,) be a partition of n and let Sc H,L1 Sk, be a "left-justified" parabolic subgroup of Sn of shape c . Define bct = Nsn,s (?), where z .4171 Nsk s, (avu)) i=1 with aw, a k,-cycle of length k, 1 in Sk . Then the main result of this paper is Theorem. The set {b, ( F n} is a basis for ZA(sn)(A(Sn)) over Q[u, u-]. Remnark. The norms b(, in ZA(sn)(A(Sn)) are analogs of conjugacy class sums in the center of QSn and, in fact, specialization of these norms at u = 1 gives the standard conjugacy class sum basis of the center of QSn up to coefficients from Q.