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arXiv · 2108.10202

Back stable K-theory Schubert calculus

Thomas Lam·Seung Jin Lee·Mark Shimozono
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Abstract

We study the back stable $K$-theory Schubert calculus of the infinite flag variety. We define back stable (double) Grothendieck polynomials and double $K$-Stanley functions and establish coproduct expansion formulae. Applying work of Weigandt, we extend our previous results on bumpless pipedreams from cohomology to $K$-theory. We study finiteness and positivity properties of the ring of back stable Grothendieck polynomials, and divided difference operators in $K$-homology.

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Thomas Lam, Seung Jin Lee, Mark Shimozono. 2021-08-23. Back stable K-theory Schubert calculus. https://arxiv.org/abs/2108.10202

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