BASEPOINT FREENESS FOR NEF AND BIG LINE BUNDLES IN POSITIVE CHARACTERISTIC, WITH APPLICATIONS TO Mg AND TO 3-FOLD MMP
نویسنده
چکیده
A general eventual freeness result is given for nef and big line bundles in positive characteristic. One application is to the geometry of the universal stable curve over Mg , specifically, the eventual freeness of the relative dualizing sheaf, in positive characteristic. An example is given which shows this fails in characteristic zero. A second application is to Mori’s program for minimal models of 3-folds in positive characteristic, namely, to the existence of birational extremal contractions. §
منابع مشابه
BASEPOINT FREENESS FOR NEF AND BIG LINE BUNDLES IN POSITIVE CHARACTERISTIC, WITH APPLICATIONS TO Mg,n AND TO 3-FOLD MMP
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