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arXiv · 1510.05079

Log canonical thresholds on group compactifications

Thibaut Delcroix
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Abstract

We compute the log canonical thresholds of non-negatively curved singular hermitian metrics on ample linearized line bundles on bi-equivariant group compactifications of complex reductive groups. To this end, we associate to any such metric a convex function whose asymptotic behavior determines the log canonical threshold. As a consequence we obtain a formula for the alpha invariant of these line bundles, in terms of the polytope associated to the group compactification.

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Thibaut Delcroix. 2015-11-16. Log canonical thresholds on group compactifications. https://doi.org/10.14231/ag-2017-010

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