Nous proposons une théorie des polynômes de Schubert doubles pour les types de Lie qui étend naturellement la famille de Lascoux et Schützenberger pour le type . Ces polynômes possèdent des propriétés de positivité, d’orthogonalité et de stabilité, et représentent les classes des variétés de Schubert et des lieux de dégénérescence des fibrés vectoriels. Quand est un élément grassmannien maximal du groupe de Weyl, s’exprime en termes de déterminants du type de Schur et de pfaffiens, de manière analogue à la formule de Kempf et Laksov pour le type . Un exemple, motivé par la cohomologie quantique, montre qu’aucune formule dans les classes de Chern ne décrit les lieux de dégénérescence des “morphismes isotropes” des fibrés.
We propose a theory of double Schubert polynomials for the Lie types , , which naturally extends the family of Lascoux and Schützenberger in type . These polynomials satisfy positivity, orthogonality and stability properties, and represent the classes of Schubert varieties and degeneracy loci of vector bundles. When is a maximal Grassmannian element of the Weyl group, can be expressed in terms of Schur-type determinants and Pfaffians, in analogy with the type formula of Kempf and Laksov. An example, motivated by quantum cohomology, shows there are no Chern class formulas for degeneracy loci of “isotropic morphisms” of bundles.
@article{AIF_2002__52_6_1681_0, author = {Kresch, Andrew and Tamvakis, Harry}, title = {Double Schubert polynomials and degeneracy loci for the classical groups}, journal = {Annales de l'Institut Fourier}, volume = {52}, year = {2002}, pages = {1681-1727}, doi = {10.5802/aif.1931}, mrnumber = {1952528}, zbl = {1059.14063}, language = {en}, url = {http://dml.mathdoc.fr/item/AIF_2002__52_6_1681_0} }
Kresch, Andrew; Tamvakis, Harry. Double Schubert polynomials and degeneracy loci for the classical groups. Annales de l'Institut Fourier, Tome 52 (2002) pp. 1681-1727. doi : 10.5802/aif.1931. http://gdmltest.u-ga.fr/item/AIF_2002__52_6_1681_0/
[AC] An algebraic formula for the Gysin homomorphism from to , Illinois J. Math, Tome 31 (1987) no. 2, pp. 312-320 | MR 882116 | Zbl 0629.57030
[Be] Quantum Schubert calculus, Adv. Math, Tome 128 (1997) no. 2, pp. 289-305 | Article | MR 1454400 | Zbl 0945.14031
[BGG] Schubert cells and cohomology of the spaces , Russian Math. Surveys, Tome 28 (1973) no. 3, pp. 1-26 | Article | MR 429933 | Zbl 0289.57024
[BH] Schubert polynomials for the classical groups, J. Amer. Math. Soc, Tome 8 (1995) no. 2, pp. 443-482 | Article | MR 1290232 | Zbl 0832.05098
[Bi] Kostant polynomials and the cohomology ring for , Duke Math. J, Tome 96 (1999) no. 1, pp. 205-224 | Article | MR 1663931 | Zbl 0980.22018
[Bo] Sur la cohomologie des espaces fibrés principaux et des espaces homogènes de groupes de Lie compacts, Ann. of Math, Tome 57 (1953), pp. 115-207 | Article | MR 51508 | Zbl 0052.40001
[BS] Schubert polynomials, the Bruhat order, and the geometry of flag manifolds, Duke Math. J, Tome 95 (1998) no. 2, pp. 373-423 | MR 1652021 | Zbl 0939.05084
[C-F] The quantum cohomology ring of flag varieties, Trans. Amer. Math. Soc, Tome 351 (1999) no. 7, pp. 2695-2729 | Article | MR 1487610 | Zbl 0920.14027
[D1] Invariants symétriques des groupes de Weyl et torsion, Invent. Math, Tome 21 (1973), pp. 287-301 | Article | MR 342522 | Zbl 0269.22010
[D2] Désingularization des variétés de Schubert généralisées, Ann. Scuola Norm. Sup. Pisa Cl. Sci (4), Tome 7 (1974), pp. 53-88 | Numdam | MR 354697 | Zbl 0312.14009
[F1] Flags, Schubert polynomials, degeneracy loci, and determinantal formulas, Duke Math. J, Tome 65 (1992) no. 3, pp. 381-420 | MR 1154177 | Zbl 0788.14044
[F2] Schubert varieties in flag bundles for the classical groups, Proceedings of the Hirzebruch 65 Conference on Algebraic Geometry (Ramat Gan, 1993) (Israel Math. Conf. Proc. 9) (1996), pp. 241-262 | Zbl 0862.14032
[F3] Determinantal formulas for orthogonal and symplectic degeneracy loci, J. Differential Geom, Tome 43 (1996) no. 2, pp. 276-290 | MR 1424427 | Zbl 0911.14001
[F4] Intersection Theory, Springer-Verlag, Berlin, Ergebnisse der Math, Tome 2 (1998) | MR 1644323 | Zbl 0885.14002
[FK] Combinatorial -analogs of Schubert polynomials, Trans. Amer. Math. Soc, Tome 348 (1996) no. 9, pp. 3591-3620 | Article | MR 1340174 | Zbl 0871.05060
[FP] Schubert varieties and degeneracy loci, Springer-Verlag, Berlin, Lecture Notes in Math, Tome 1689 (1998) | MR 1639468 | Zbl 0913.14016
[Gra] The class of the diagonal in flag bundles, J. Differential Geom, Tome 45 (1997) no. 3, pp. 471-487 | MR 1472885 | Zbl 0935.14015
[Gro] Techniques de construction et théorèmes d'existence en géométrie algébrique IV: Les schémas de Hilbert, Séminaire Bourbaki 13 (1960/61) no. 221 | Numdam | Zbl 0236.14003
[HT] On symmetric and skew-symmetric determinantal varieties, Topology, Tome 23 (1984) no. 1, pp. 71-84 | Article | MR 721453 | Zbl 0534.55010
[JLP] Classes of determinantal varieties associated with symmetric and skew-symmetric matrices, Math. USSR Izvestija, Tome 18 (1982), pp. 575-586 | Article | MR 623355 | Zbl 0489.14020
[KL] The determinantal formula of Schubert calculus, Acta Math, Tome 132 (1974), pp. 153-162 | Article | MR 338006 | Zbl 0295.14023
[KT2] Quantum cohomology of orthogonal Grassmannians (2001) (Preprint) | MR 2027200
[L] Classes de Chern des variétés de drapeaux, C. R. Acad. Sci. Paris, Sér. I Math, Tome 295 (1982) no. 5, pp. 393-398 | MR 684734 | Zbl 0495.14032
[LP1] Operator calculus for -polynomials and Schubert polynomials, Adv. Math, Tome 140 (1998) no. 1, pp. 1-43 | Article | MR 1656481 | Zbl 0951.14035
[LP2] Orthogonal divided differences and Schubert polynomials, -functions, and vertex operators, Michigan Math. J, Tome 48 (2000), pp. 417-441 | Article | MR 1786499 | Zbl 1003.05106
[LP3] Schur -functions and degeneracy locus formulas for morphisms with symmetries, Birkhäuser, Boston (Recent Progress in Intersection Theory) (2000), pp. 239-263 | Zbl 0969.14033
[LS] Polynômes de Schubert, C. R. Acad. Sci. Paris, Sér. I Math, Tome 294 (1982) no. 13, pp. 447-450 | MR 660739 | Zbl 0495.14031
[M1] Notes on Schubert polynomials, Publ. LACIM, Univ. de Québec à Montréal, Montréal Tome 6 (1991) | MR 1161461
[M2] Schubert polynomials, Surveys in combinatorics, 1991 (Guildford, 1991), Cambridge Univ. Press, Cambridge (L.M.S. Lecture Note Series) Tome 166 (1991), pp. 73-99 | Zbl 0784.05061
[M3] Symmetric Functions and Hall Polynomials, Clarendon Press, Oxford (1995) | MR 1354144 | Zbl 0824.05059
[P1] Cycles of isotropic subspaces and formulas for symmetric degeneracy loci, Topics in Algebra, Part 2 (Warsaw, 1988), Banach Center Publ, Part 2, PWN, Warsaw, Tome 26 (1990), pp. 189-199 | Zbl 0743.14009
[P2] Algebro-geometric applications of Schur - and -polynomials, Séminaire d'Algèbre Dubreil-Malliavin 1989-1990, Springer-Verlag, Berlin (Lecture Notes in Math) Tome 1478 (1991), pp. 130-191 | Zbl 0783.14031
[PR1] A Pieri-type theorem for Lagrangian and odd orthogonal Grassmannians, J. reine angew. Math, Tome 476 (1996), pp. 143-189 | MR 1401699 | Zbl 0847.14029
[PR2] Formulas for Lagrangian and orthogonal degeneracy loci; -polynomial approach, Compositio Math, Tome 107 (1997) no. 1, pp. 11-87 | Article | MR 1457343 | Zbl 0916.14026
[S] Über die Darstellung der symmetrischen und der alternierenden Gruppe durch gebrochene lineare Substitutionen, J. reine angew. Math, Tome 139 (1911), pp. 155-250 | Article | JFM 42.0154.02
[Ta] Arakelov theory of the Lagrangian Grassmannian, J. reine angew. Math, Tome 516 (1999), pp. 207-223 | Article | MR 1724621 | Zbl 0934.14018
[Tu] Degeneracy loci, Proc. conf. algebraic geom. (Berlin, 1985), Teubner, Leipzig (Teubner-Texte Math) Tome 92 (1986), pp. 296-305 | Zbl 0626.14019
[KT1] Quantum cohomology of the Lagrangian Grassmannian (J. Algebraic Geometry, to appear) | MR 1993764 | Zbl 1051.53070