NORMALITY AND QUADRATICITY FOR SPECIAL AMPLE LINE BUNDLES ON TORIC VARIETIES ARISING FROM ROOT SYSTEMS

GASHI, QËNDRIM R. ; SCHEDLER, TRAVIS

Glasgow mathematical journal, Tome 55 (2013) no. A, pp. 113-134

Résumé

We prove that special ample line bundles on toric varieties arising from root systems are projectively normal. Here the maximal cones of the fans correspond to the Weyl chambers, and special means that the bundle is torus-equivariant such that the character of the line bundle that corresponds to a maximal Weyl chamber is dominant with respect to that chamber. Moreover, we prove that the associated semi-group rings are quadratic.

Détail

DOI : 10.1017/S0017089513000542

Mots-clés : 17B22, 14M25

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