Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Peak algebras, paths in the Bruhat graph and Kazhdan-Lusztig polynomials   We give a new characterization of the peak subalgebra of the algebra of
quasisymmetric functions and use this to construct a new basis for this
subalgebra. As an application of these results we obtain a combinatorial
formula for the Kazhdan-Lusztig polynomials which holds in complete generality
and is simpler and more explicit than any existing one. We then show that, in a
certain sense, this formula cannot be simplified.

23
The categories of this paper are: solv-int
8
The categories of this paper are: hep-ex
10
The categories of this paper are: q-bio
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
24
The categories of this paper are: dg-ga
19
The categories of this paper are: eess
4
The categories of this paper are: cond-mat
9
The categories of this paper are: nlin
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph
29
The categories of this paper are: funct-an
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
12
The categories of this paper are: nucl-th
6
The categories of this paper are: astro-ph