W-translated Schubert divisors and transversal intersections

Science China Mathematics - Tập 65 - Trang 1997-2018 - 2022
DongSeon Hwang1,2, Hwayoung Lee3, Jae-Hyouk Lee4, Changzheng Li5
1Department of Mathematics, Ajou University, Suwon, Republic of Korea
2Current address: Center for Complex Geometry, Institute for Basic Science (IBS), Daejeon, Republic of Korea
3Department of Mathematics, University of California Riverside, Riverside, USA
4Department of Mathematics, Ewha Womans University, Seoul, Republic of Korea
5School of Mathematics, Sun Yat-sen University, Guangzhou, China

Tóm tắt

We study the toric degeneration of Weyl group translated Schubert divisors of a partial flag variety $$F{\ell _{{n_1}, \ldots,{n_k};n}}$$ via Gelfand-Cetlin polytopes. We propose a conjecture that Schubert varieties of appropriate dimensions intersect transversally up to translation by Weyl group elements, and verify it in various cases, including the complex Grassmannian Gr(2, n) and the complete flag variety Fℓ1,2,3,4.

Tài liệu tham khảo

Batyrev V, Ciocan-Fontanine I, Kim B, et al. Mirror symmetry and toric degenerations of partial flag manifolds. Acta Math, 2000, 184: 1–39 Billey S, Coskun I. Singularities of generalized Richardson varieties. Comm Algebra, 2012, 40: 1466–1495 Billey S, Lakshmibai V. Singular Loci of Schubert Varieties. Progress in Mathematics, vol. 182. Boston: Birkhäuser, 2000 Bouloc D, Miranda E, Zung N T. Singular fibres of the Gelfand-Cetlin system on \({\mathfrak{u}(n)^\ast}\). Philos Trans Roy Soc A, 2018, 376: 20170423 Buch A S. Mutations of puzzles and equivariant cohomology of two-step flag varieties. Ann of Math (2), 2015, 182: 173–220 Buch A S, Kresch A, Purbhoo K, et al. The puzzle conjecture for the cohomology of two-step flag manifolds. J Algebraic Combin, 2016, 44: 973–1007 Chan K, Leung N C, Li C. Pseudotoric structures and special Lagrangian torus fibrations on certain flag varieties. J Geom Phys, 2019, 146: 103489 Cho Y, Kim Y, Oh Y-G. Lagrangian fibers of Gelfand-Cetlin systems. Adv Math, 2020, 372: 107304 Coskun I. A Littlewood-Richardson rule for two-step flag varieties. Invent Math, 2009, 176: 325–395 Cox D A, Little J B, Schenck H K. Toric Varieties. Graduate Studies in Mathematics, vol. 124. Providence: Amer Math Soc, 2011 Duan H. Multiplicative rule of Schubert class. Invent Math, 2005, 159: 407–436 Fulton W, Woodward C. On the quantum product of Schubert classes. J Algebraic Geom, 2004, 13: 641–661 Gonciulea N, Lakshmibai V. Degenerations of flag and Schubert varieties to toric varieties. Transform Groups 1996, 1: 215–248 Hartshorne R. Algebraic Geometry. Graduate Texts in Mathematics, vol. 52. New York-Berlin: Springer-Verlag, 1977 Hibi T. Distributive lattices, affine semigroup rings and algebras with straightening laws. In: Commutative Algebra and Combinatorics. Advanced Studies in Pure Mathematics, vol. 11. Amsterdam: North-Holland, 1987, 93–109 Huang Y, Li C. On equivariant quantum Schubert calculus for G/P. J Algebra, 2015, 441: 21–56 Karp S. Moment curves and cyclic symmetry for positive Grassmannians. Bull Lond Math Soc, 2019, 51: 900–916 Kaveh K. Note on cohomology rings of spherical varieties and volume polynomial. J Lie Theory, 2011, 21: 263–283 Kiritchenko V. Gelfand-Zetlin polytopes and flag varieties. Int Math Res Not IMRN, 2010, 2010: 2512–2531 Kiritchenko V, Smirnov E, Timorin V. Schubert calculus and Gelfand-Zetlin polytopes. Russian Math Surveys, 2012, 67: 685–719 Kleiman S. The transversality of a general translate. Compos Math, 1974, 28: 287–297 Knutson A. A Schubert Calculus recurrence from the non-complex W-action on G/B. arXiv:0306304, 2003 Knutson A, Lam T, Speyer D. Projections of Richardson varieties. J Reine Angew Math, 2014, 687: 133–157 Knutson A, Miller E. Gröbner geometry of Schubert polynomials. Ann of Math (2), 2005, 161: 1245–1318 Knutson A, Zinn-Justin P. Schubert puzzles and integrability I: Invariant trilinear forms. arXiv:1706.10019, 2017 Kogan M. Schubert geometry of flag varieties and Gelfand-Cetlin theory. PhD Thesis. Cambridge: Massachusetts Institute of Technology, 2000 Kogan M, Miller E. Toric degeneration of Schubert varieties and Gelfand-Tsetlin polytopes. Adv Math, 2005, 193: 1–17 Lakshmibai V, Raghavan K N. Standard Monomial Theory. Invariant Theoretic Approach. Encyclopedia of Mathematical Sciences, vol. 137. Berlin-Heidelberg: Springer-Verlag, 2008 Leung N C, Li C. Classical aspects of quantum cohomology of generalized flag varieties. Int Math Res Not IMRN, 2012, 2012: 3706–3722 Marsh R, Rietsch K. The B-model connection and mirror symmetry for Grassmannians. Adv Math, 2020, 366: 107027 Nishinou T, Nohara Y, Ueda K. Toric degenerations of Gelfand-Cetlin systems and potential functions. Adv Math, 2010, 224: 648–706 Pukhlikov A V, Khovanskii A G. The Riemann-Roch theorem for integrals and sums of quasipolynomials on virtual polytopes. St Petersburg Math J, 1993, 4: 789–812 Sottile F. Rational curves on Grassmannians: Systems theory, reality, and transversality. In: Advances in Algebraic Geometry Motivated by Physics. Contemporary Mathematics, vol. 276. Providence: Amer Math Soc, 2001, 9–2 Sottile F. General isotropic flags are general (for Grassmannian Schubert calculus). J Algebraic Geom, 2010, 19: 367–370 Strominger A, Yau S-T, Zaslow E. Mirror symmetry is T-duality. Nuclear Phys B, 1996, 479: 243–259 Timorin V A. An analogue of the Hodge-Riemann relations for simple convex polytopes. Russian Math Surveys, 1999, 54: 381–426 Vakil R. A geometric Littlewood-Richardson rule. Ann of Math (2), 2006, 164: 371–421