2
votes
0answers
117 views
Edge graph of the polytope of a Bruhat interval
Let $\Gamma$ be a Coxeter group on some generating set $S$, with reflection representation $V$. Then $\Gamma$ has two standard partial orders, the weak and strong Bruhat orders.
M …
14
votes
3answers
421 views
Kazhdan-Luzstig Polynomials and Lower Intervals in the Bruhat Order
I have read in a number of places that the lower Bruhat interval $[e, w]$ is rank-symmetric if and only if the KL-polynomial $P_{e, w}(q) = 1$. All of the proofs I've come across u …
14
votes
1answer
405 views
Bruhat order and the Robinson-Schensted correspondence
The Robinson-Schensted correspondence is a bijection between elements of the symmetric group $S_n$ and pairs of standard tableaux of the same shape. The symmetric group is partial …
5
votes
1answer
215 views
Efficient enumeration of Bruhat intervals
Hi everyone.
I'm currently programming some stuff for Hecke algebras. My current implementations have several bottlenecks and I'd like to improve that as much as I can so that I c …
3
votes
0answers
131 views
Are plactic classes convex under the right weak Bruhat order?
For those who are unfamiliar with the terminology, I'll explain a little.
The symmetric group $S_n$, as a type A Coxeter group, has generators ${s_1,\ldots,s_{n-1}}$ with relation …
2
votes
1answer
192 views
Reference for: the Bruhat-minimal permutations not less than a fixed permutation pi?
Let $\pi\in S_n$. I recently needed to understand the permutations $\rho$ such that $\rho\not\leq\pi$ in Bruhat order. Since there are $O(n!)$ of those I really wanted a descriptio …

