Abstract We study a class of combinatorially defined polynomial ideals that are generated by minors of a generic symmetric matrix. Included within this class are the symmetric determinantal ideals, the symmetric ladder determinantal ideals, and the symmetric Schubert determinantal ideals of A. Fink, J. Rajchgot, and S. Sullivant. Each ideal in our class is a type C analog of a Kazhdan–Lusztig ideal of A. Woo and A. Yong; that is, it is the scheme‐theoretic defining ideal of the intersection of a type C Schubert variety with a type C opposite Schubert cell, appropriately coordinatized. The Kazhdan–Lusztig ideals that arise are exactly those where the opposite cell is 123‐avoiding. Our main results include Gröbner bases for these ideals, prime decompositions of their initial ideals (which are Stanley–Reisner ideals of subword complexes), and combinatorial formulas for their multigraded Hilbert series in terms of pipe dreams.
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Asymptotic Hecke Algebras and Lusztig–Vogan Bijection via Affine Matrix-Ball Construction
Abstract The affine matrix-ball construction (abbreviated AMBC) was developed by Chmutov, Lewis, Pylyavskyy, and Yudovina as an affine generalization of the Robinson–Schensted correspondence. We show that AMBC gives a simple way to compute a distinguished involution in each Kazhdan–Lusztig cell of an affine symmetric group. We then use AMBC to give the 1st known canonical presentation for the asymptotic Hecke algebras of extended affine symmetric groups. As an application, we show that AMBC gives a conceptual way to compute the Lusztig–Vogan bijection. For the latter, we build upon prior works of Achar and Rush.
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- Award ID(s):
- 1949896
- PAR ID:
- 10527476
- Publisher / Repository:
- Oxford
- Date Published:
- Journal Name:
- International Mathematics Research Notices
- Volume:
- 2023
- Issue:
- 18
- ISSN:
- 1073-7928
- Page Range / eLocation ID:
- 16051 to 16103
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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