Soit un sous-groupe fermé réductif et connexe d’un groupe réductif complexe et connexe . On fixe des tores maximaux et des sous-groupes de Borel de et . De cette manière les représentations irréductibles de et sont paramétrées par des poids dominants. On s’intéresse au cône engendré par les paires de poids dominants réguliers tels que est un sous--module de . Nous obtenons ici une paramétrisation bijective des faces de , en étudiant plus généralement les GIT-cônes des -variétés projectives. Nous montrons aussi comment les relations d’inclusions entre les faces de se lisent sur notre paramétrisation.
Let be a connected reductive subgroup of a complex connected reductive group . Fix maximal tori and Borel subgroups of and . Consider the cone generated by the pairs of strictly dominant characters such that is a submodule of . We obtain a bijective parametrization of the faces of as a consequence of general results on GIT-cones. We show how to read the inclusion of faces off this parametrization.
@article{AIF_2011__61_4_1467_0, author = {Ressayre, Nicolas}, title = {Geometric Invariant Theory and Generalized Eigenvalue Problem II}, journal = {Annales de l'Institut Fourier}, volume = {61}, year = {2011}, pages = {1467-1491}, doi = {10.5802/aif.2647}, zbl = {1245.14045}, mrnumber = {2951500}, language = {en}, url = {http://dml.mathdoc.fr/item/AIF_2011__61_4_1467_0} }
Ressayre, Nicolas. Geometric Invariant Theory and Generalized Eigenvalue Problem II. Annales de l'Institut Fourier, Tome 61 (2011) pp. 1467-1491. doi : 10.5802/aif.2647. http://gdmltest.u-ga.fr/item/AIF_2011__61_4_1467_0/
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