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

Published online by Cambridge University Press:  01 October 2013

QËNDRIM R. GASHI
Affiliation:
Department of Mathematics, University of Prishtina, Pristina 10000, Kosovo e-mail: qendrim@gmail.com
TRAVIS SCHEDLER
Affiliation:
Department of Mathematics, The University of Texas at Austin 2515 Speedway, Austin, TX 78712-1202, USA e-mail: trasched@gmail.com
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Abstract

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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.

Keywords

Type
Research Article
Copyright
Copyright © Glasgow Mathematical Journal Trust 2013 

References

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