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arXiv · 1504.01469

On Double Schubert and Grothendieck polynomials for Classical Groups

A. N. Kirillov
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Abstract

We give an algebra-combinatorial constructions of (noncommutative) generating functions of double Schubert and double $\beta$-Grothendieck polynomials corresponding to the full flag varieties associated to the Lie groups of classical types $A,B, C$ and $D$. Our approach is based on the decomposition of certain `` transfer matrices `` corresponding to the exponential solution to the quantum Yang--Baxter equations associated with either NiCoxeter or IdCoxeter algebras of classical types. The "triple"~$\beta$-Grothendieck polynomials ${\mathfrak{G}}_{w}^{W}(X,Y,Z)$ we have introduced, satisfy, among other things, the coherency and (generalized) vanishing conditions. Their generating function has a nice factorization in the algebra $Id_{\beta}Coxeter(W)$, and as a consequence, the polynomials ${\mathfrak{G}}_{w}^{W}(X,Y,Z)$ admit a combinatorial description in terms of $W$-type pipe dreams.

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A. N. Kirillov. 2015-04-07. On Double Schubert and Grothendieck polynomials for Classical Groups. https://arxiv.org/abs/1504.01469

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