关于逆Kazhdan-Lusztig多项式Q_(A,C)

本文说明逆Kazhdan-Lusztig多项式的某些性质,通过Lusztig猜想反映了代数群表示理论中的某些事实。     

关于对偶扩张拟遗传代数的Kazhdan-Lusztig理论

In order to study the representation theory of Lie algebras and algebraic groups, Cline, Parshall and Scott put forward the notion of abstract Kazhdan-Lusztig theory for quasihereditary algebras. Assume that a quasi-hereditary algebra B has the vertex set Q0 = {1,..., n} such that HomB（P（i）, P（j）） = 0 for i 〉 j. In this paper, it is shown that if the quasi-hereditary algebra B has a Kazhdan-Lusztig theory relative to a length function l, then its dual extension algebra A = .A（B） has also the Kazhdan-Lusztig theory relative to the length function l.     

多项式理论

为了参加国际奥林匹克教学竞赛,我国从86年开始,每年都举办了集训班,本文是用作者在86,87两届集训班上所作的讲稿整理而成,文中先叙述基础知识,再给出若干典型例子。叙述如何思考,但不证完,读者很容易补足。     

反证法在多项式理论中的应用

表达一个判断的语句称为命题,命题是由题设和题断构成。证明一个命题成立,有直接证法和间接证法。反证法属于间接证法。一般来说,大多数命题的证明是由直接证法给出的,但是当直接证法不易证明甚至无法证明时,运用反证法,有时可以收到证明既简练又确切的良好效果。因此反证法是一种重要的证明方法。然而多年来,一些人有片面的认识,认为反     

二项式型自反多项式

In this paper, we define the self-inverse sequences related to sequences of polynomials of binomial type, and give some interesting results of these sequences. Moreover, we study the self-inverse sequences related to the Laguerre polynomials.     

三角多项式类中的Birkhoff型三角插值

本文在三角多项式类中讨论了2π周期函数的一类Birkhoff型等距结点的三角插值问题,给出了此问题有解的充要条件,并构造出插值基.     

多项式理论(续)

§6 有理系数和整系数多项式的根 引理21 设■为整系数多项式,且为本原多项式,即(α_0,α_1,…,α_n)=1。则f的整数根α|α_0;有理数根α=u/2,(u,v)=1有u|α_0,v|α_n。     

Born-Infeld理论中的多项式函数模型（英文）

Based on the Lagrangian action density under Born-Infeld type dynamics and motivated by the one-dimensional prescribed mean curvature equation, we investigate the polynomial function model in Born-Infeld theory in this paper with the form of-([1-a(φ)2]φ) = λf(φ(x)),where λ > 0 is a real parameter, f ∈ C²(0, +∞) is a nonlinear function. We are interested in the exact number of positive solutions of the above nonlinear equation. We specifically develop for the problem combined with a...     

Kazhdan-Lusztig理论:起源、发展、影响和一些待解决的问题

Kazhdan-Lusztig理论是代数群表示论近40年来最重要的发展之一.该理论在很多重要问题的解决上起关键作用,如有限Lie型群的不可约特征标的分类和Lie理论中某些不可约表示的特征标的确定等.同时该理论开创了很多有活力的研究课题,如Kazhdan-Lusztig多项式的研究、Coxeter群的胞腔的研究及Coxeter群与相交上同调和K理论的联系等.本文将简要介绍这一理论的起源、发展、影响和一些未解决的问题.     

An型扭双指标代数

给出了(ふ)(Δ)-有限的An型偏序集的扭双指标代数的完全分类.     

On the combinatorial invariance of Kazhdan-Lusztig polynomials

In this paper, we solve the conjecture about the combinatorial invariance of Kazhdan-Lusztig polynomials for the first open cases, showing that it is true for intervals of length 5 and 6 in the symmetric group. We also obtain explicit formulas for the R-polynomials and for the Kazhdan-Lusztig polynomials associated with any interval of length 5 in any Coxeter group, showing in particular what they look like in the symmetric group.     

Explicit Formulae for Some Kazhdan-Lusztig Polynomials

We consider the Kazhdan-Lusztig polynomials P _u,v (q) indexed by permutations u, v having particular forms with regard to their monotonicity patterns. The main results are the following. First we obtain a simplified recurrence relation satisfied by P _u,v (q) when the maximum value of v S_n occurs in position n – 2 or n – 1. As a corollary we obtain the explicit expression for P_{e,3 4 ... n 1 2}(q) (where e denotes the identity permutation), as a q-analogue of the Fibonacci number. This establishes a conjecture due to M. Haiman. Second, we obtain an explicit expression for P_{e, 3 4 ... (n – 2) n (n – 1) 1 2}(q). Our proofs rely on the recurrence relation satisfied by the Kazhdan-Lusztig polynomials when the indexing permutations are of the form under consideration, and on the fact that these classes of permutations lend themselves to the use of induction. We present several conjectures regarding the expression for P _u,v (q) under hypotheses similar to those of the main results.     

Combinatorial invariance of Kazhdan-Lusztig polynomials on intervals starting from the identity

We show that for Bruhat intervals starting from the identity in Coxeter groups the conjecture of Lusztig and Dyer holds, that is, the R-polynomials and the Kazhdan-Lusztig polynomials defined on [e,u] only depend on the isomorphism type of [e,u]. To achieve this we use the purely poset-theoretic notion of special matching. Our approach is essentially a synthesis of the explicit formula for special matchings discovered by Brenti and the general special matching machinery developed by Du Cloux.     

Lattice paths and Kazhdan-Lusztig polynomials

The purpose of this paper is to present a new non-recursive combinatorial formula for the Kazhdan-Lusztig polynomials of a Coxeter group . More precisely, we show that each directed path in the Bruhat graph of has a naturally associated set of lattice paths with the property that the Kazhdan-Lusztig polynomial of is the sum, over all the lattice paths associated to all the paths going from to , of where , and are three natural statistics on the lattice path.

     

Proof of Two Conjectures of Brenti and Simion on Kazhdan-Lusztig Polynomials

We find an explicit formula for the Kazhdan-Lusztig polynomials P _ui,a,v _i of the symmetric group (n) where, for a, i, n such that 1 a i n, we denote by u _i,a = s _a s _a+1 ··· s _i–1 and by v _i the element of (n) obtained by inserting n in position i in any permutation of (n – 1) allowed to rise only in the first and in the last place. Our result implies, in particular, the validity of two conjectures of Brenti and Simion [4, Conjectures 4.2 and 4.3], and includes as a special case a result of Shapiro, Shapiro and Vainshtein [13, Theorem 1]. All the proofs are purely combinatorial and make no use of the geometry of the corresponding Schubert varieties.     

The quantum general linear supergroup,canonical bases and Kazhdan-Lusztig polynomials

Canonical bases of the tensor powers of the natural -module V are constructed by adapting the work of Frenkel, Khovanov and Kirrilov to the quantum supergroup setting. This result is generalized in several directions. We first construct the canonical bases of the ℤ₂-graded symmetric algebra of V and tensor powers of this superalgebra; then construct canonical bases for the superalgebra O _q (M _m|n ) of a quantum (m,n) × (m,n)-supermatrix; and finally deduce from the latter result the canonical basis of every irreducible tensor module for by applying a quantum analogue of the Borel-Weil construction. This work was supported by National Natural Science Foundation of China (Grant No. 10471070)     

Irreducible W-Graphs for Type D 4 and D 5

ABSTRACT

The “W-graph” concept was introduced by Kazhdan and Lusztig in their influential article Kazhdan and Lusztig (1979 Kazhdan , D. , Lusztig , G. ( 1979 ). Representations of Coxeter groups and Hecke algebras . Invent. Math. 53 : 165 – 184 . [CROSSREF] [CSA] [Crossref], [Web of Science ®] , [Google Scholar]). If W is a Coxeter group, then a W-graph provides a method for constructing a matrix representation of the Hecke algebra ? associated with W (the degree of the representation being the number of vertices of the W-graph). The aim of this note is to explicitly construct all the irreducible representations of ? when W is of type D ₄ and D ₅.     

Centralizers of Iwahori-Hecke Algebras II: The General Case

This paper is a sequel to [4]. We establish the minimal basis theory for the centralizers of parabolic subalgebras of Iwahori-Hecke algebras associated to finite Coxeter groups of any type, generalizing the approach introduced in [3] from centres to the centralizer case. As a pro-requisite, we prove a reducibility property in the twisted J-conjugacy classes in finite Coxeter groups, which is a generalization of results in [7] and [4].2000 Mathematics Subject Classification: 20C08, 20F55     

Classification of graded Hecke algebras for complex reflection groups

The graded Hecke algebra for a finite Weyl group is intimately related to the geometry of the Springer correspondence. A construction of Drinfeld produces an analogue of a graded Hecke algebra for any finite subgroup of GL(V). This paper classifies all the algebras obtained by applying Drinfeld's construction to complex reflection groups. By giving explicit (though nontrivial) isomorphisms, we show that the graded Hecke algebras for finite real reflection groups constructed by Lusztig are all isomorphic to algebras obtained by Drinfeld's construction. The classification shows that there exist algebras obtained from Drinfeld's construction which are not graded Hecke algebras as defined by Lusztig for real as well as complex reflection groups. Received: July 25, 2001