Newton polytopes of dual Schubert polynomials
Algebraic Combinatorics, Volume 8 (2025) no. 6, pp. 1459-1472

The M-convexity of dual Schubert polynomials was first proven by Huh, Matherne, Mészáros, and St. Dizier in 2022. We give a full characterization of the support of dual Schubert polynomials, which yields an elementary alternative proof of the M-convexity result, and furthermore strengthens it by explicitly characterizing the vertices of their Newton polytopes combinatorially. Using this characterization, we give a polynomial-time algorithm to determine if a coefficient of a dual Schubert polynomial is zero, analogous to a result of Adve, Robichaux, and Yong for Schubert polynomials.

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DOI: 10.5802/alco.450
Classification: 05E05, 14N15, 52B40
Keywords: Newton polytope, dual Schubert polynomial, M-convex

An, Serena 1; Tung, Katherine 2; Zhang, Yuchong 3

1 Massachusetts Institute of Technology, Department of Mathematics, Cambridge, MA 02139 (USA)
2 Harvard University, Department of Mathematics, Cambridge, MA 02138 (USA)
3 University of Michigan, Department of Mathematics, Ann Arbor, MI 48109 (USA)
License: CC-BY 4.0
Copyrights: The authors retain unrestricted copyrights and publishing rights
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An, Serena; Tung, Katherine; Zhang, Yuchong. Newton polytopes of dual Schubert polynomials. Algebraic Combinatorics, Volume 8 (2025) no. 6, pp. 1459-1472. doi: 10.5802/alco.450

[1] Adve, Anshul; Robichaux, Colleen; Yong, Alexander An efficient algorithm for deciding vanishing of Schubert polynomial coefficients, Adv. Math., Volume 383 (2021), Paper no. 107669, 38 pages | DOI | MR | Zbl

[2] Agnarsson, Geir; Morris, Walter D. On Minkowski sums of simplices, Ann. Comb., Volume 13 (2009) no. 3, pp. 271-287 | DOI | MR | Zbl

[3] An, Serena; Tung, Katherine; Zhang, Yuchong Postnikov–Stanley polynomials are Lorentzian, 2024 | arXiv | Zbl

[4] Ardila, Federico; Benedetti, Carolina; Doker, Jeffrey Matroid polytopes and their volumes, Discrete Comput. Geom., Volume 43 (2010) no. 4, pp. 841-854 | DOI | MR | Zbl

[5] Bernstein, Joseph; Gelfand, Israel; Gelfand, Sergei Schubert cells and cohomology of the spaces G/P, Russian Mathematical Surveys, Volume 28 (1973), pp. 1-26 | DOI | Zbl

[6] Björner, Anders; Brenti, Francesco Combinatorics of Coxeter groups, Graduate Texts in Mathematics, 231, Springer, New York, 2005, xiv+363 pages | MR | Zbl

[7] Castillo, Federico; Cid-Ruiz, Yairon; Mohammadi, Fatemeh; Montaño, Jonathan Double Schubert polynomials do have saturated Newton polytopes, Forum Math. Sigma, Volume 11 (2023), Paper no. e100, 9 pages | DOI | MR | Zbl

[8] Fink, Alex; Mészáros, Karola; St. Dizier, Avery Schubert polynomials as integer point transforms of generalized permutahedra, Adv. Math., Volume 332 (2018), pp. 465-475 | DOI | MR | Zbl

[9] Gao, Yibo An involution on RC-graphs and a conjecture on dual Schubert polynomials by Postnikov and Stanley, Algebr. Comb., Volume 3 (2020) no. 3, pp. 593-602 | DOI | MR | Numdam | Zbl

[10] Gelʼfand, I. M.; Kapranov, M. M.; Zelevinsky, A. V. Newton polytopes of the classical resultant and discriminant, Adv. Math., Volume 84 (1990) no. 2, pp. 237-254 | DOI | MR | Zbl

[11] Hamaker, Zachary Dual Schubert polynomials via a Cauchy identity, 2023 | arXiv | Zbl

[12] Huh, June; Matherne, Jacob P.; Mészáros, Karola; St. Dizier, Avery Logarithmic concavity of Schur and related polynomials, Trans. Amer. Math. Soc., Volume 375 (2022) no. 6, pp. 4411-4427 | DOI | MR | Zbl

[13] Micali, Silvio; Vazirani, Vijay An O(|V||E|) algorithm for finding maximum matching in general graphs, 21st Annual Symposium on Foundations of Computer Science (1980), pp. 17-27 | DOI

[14] Monical, Cara; Tokcan, Neriman; Yong, Alexander Newton polytopes in algebraic combinatorics, Selecta Math. (N.S.), Volume 25 (2019) no. 5, Paper no. 66, 37 pages | DOI | MR | Zbl

[15] Murota, Kazuo Discrete convex analysis, SIAM Monographs on Discrete Mathematics and Applications, Society for Industrial and Applied Mathematics (SIAM), Philadelphia, PA, 2003, xxii+389 pages | DOI | MR | Zbl

[16] Postnikov, Alexander Permutohedra, associahedra, and beyond, Int. Math. Res. Not. IMRN (2009) no. 6, pp. 1026-1106 | DOI | MR | Zbl

[17] Postnikov, Alexander; Stanley, Richard P. Chains in the Bruhat order, J. Algebraic Combin., Volume 29 (2009) no. 2, pp. 133-174 | DOI | MR | Zbl

[18] Rado, Richard An inequality, J. London Math. Soc., Volume 27 (1952), pp. 1-6 | DOI | MR | Zbl

[19] Sage Developers, The SageMath, the Sage Mathematics Software System (Version 10.4) (2024) https://www.sagemath.org

[20] Stanley, Richard Catalan addendum to Enumerative Combinatorics. Vol. 2., 2013 https://math.mit.edu/~rstan/ec/catadd.pdf

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