## Positivity in $T$-equivariant $K$-theory of flag varieties associated to Kac-Moody groups II

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- by Seth Baldwin and Shrawan Kumar
- Represent. Theory
**21**(2017), 35-60 - DOI: https://doi.org/10.1090/ert/494
- Published electronically: March 24, 2017
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## Abstract:

We prove sign-alternation of the structure constants in the basis of the structure sheaves of opposite Schubert varieties in the torus-equivariant Grothendieck group of coherent sheaves on the flag varieties $G/P$ associated to an arbitrary symmetrizable Kac-Moody group $G$, where $P$ is any parabolic subgroup. This generalizes the work of Anderson-Griffeth-Miller from the finite case to the general Kac-Moody case, and affirmatively answers a conjecture of Lam-Schilling-Shimozono regarding the signs of the structure constants in the case of the affine Grassmannian.## References

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## Bibliographic Information

**Seth Baldwin**- Affiliation: Department of Mathematics, University of North Carolina, Chapel Hill, North Carolina 27599-3250
- Email: seth.baldwin@unc.edu
**Shrawan Kumar**- Affiliation: Department of Mathematics, University of North Carolina, Chapel Hill, North Carolina 27599-3250
- MR Author ID: 219351
- Email: shrawan@email.unc.edu
- Received by editor(s): December 4, 2016
- Published electronically: March 24, 2017
- © Copyright 2017 American Mathematical Society
- Journal: Represent. Theory
**21**(2017), 35-60 - MSC (2010): Primary 19L47; Secondary 14M15
- DOI: https://doi.org/10.1090/ert/494
- MathSciNet review: 3627147