Abstract
The geometric naturality of Schubert polynomials and their combinatorial pipe dream representations was established by Knutson and Miller (2005) via antidiagonal Gröbner degeneration of matrix Schubert varieties. We consider instead diagonal Gröbner degenerations. In this dual setting, Knutson, Miller, and Yong (2009) obtained alternative combinatorics for the class of “vexillary” matrix Schubert varieties. We initiate a study of general diagonal degenerations, relating them to a neglected formula of Lascoux (2002) in terms of the 6-vertex ice model (recently rediscovered by Lam, Lee, and Shimozono (2018) in the guise of “bumpless pipe dreams”).
Original language | English (US) |
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Article number | #5 |
Journal | Seminaire Lotharingien de Combinatoire |
Issue number | 85 |
State | Published - 2021 |
Externally published | Yes |
Bibliographical note
Funding Information:∗[email protected] †[email protected] Oliver Pechenik was partially supported by a Mathematical Postdoctoral Research Fellowship (#1703696) from the National Science Foundation. ‡[email protected]
Publisher Copyright:
© 2021, Seminaire Lotharingien de Combinatoire. All Rights Reserved.
Keywords
- bumpless pipe dream
- matrix Schubert variety
- Schubert polynomial