[Schéma quot et semi-positivité de Ricci]
Soit X une surface de Riemann compacte et connexe de genre au moins deux, et soit le schéma quot qui paramétrise tous les quotients torsion cohérents de de degré d. L'espace est aussi un espace de modules de vortex sur X. Nous démontrons que le fibré anticanonique de X n'a pas la propriété nef. De façon équivalente, n'admet aucune métrique kählérienne dont la courbure de Ricci soit semi-positive.
Let X be a compact connected Riemann surface of genus at least two, and let be the quot scheme that parameterizes all the torsion coherent quotients of of degree d. This is also a moduli space of vortices on X. Its geometric properties have been extensively studied. Here we prove that the anticanonical line bundle of is not nef. Equivalently, does not admit any Kähler metric whose Ricci curvature is semipositive.
Accepté le :
Publié le :
Indranil Biswas 1 ; Harish Seshadri 2
@article{CRMATH_2017__355_5_577_0, author = {Indranil Biswas and Harish Seshadri}, title = {Quot schemes and {Ricci} semipositivity}, journal = {Comptes Rendus. Math\'ematique}, pages = {577--581}, publisher = {Elsevier}, volume = {355}, number = {5}, year = {2017}, doi = {10.1016/j.crma.2017.03.012}, language = {en}, }
Indranil Biswas; Harish Seshadri. Quot schemes and Ricci semipositivity. Comptes Rendus. Mathématique, Volume 355 (2017) no. 5, pp. 577-581. doi : 10.1016/j.crma.2017.03.012. https://comptes-rendus.academie-sciences.fr/mathematique/articles/10.1016/j.crma.2017.03.012/
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