CYCLIC COVERING MORPHISMS ON M0,n
نویسنده
چکیده
We study cyclic covering morphisms from M0,n to moduli spaces of unpointed stable curves of positive genus or compactified moduli spaces of principally polarized abelian varieties. Our main application is a construction of new semipositive vector bundles and nef divisors on M0,n, with a view toward the F-conjecture. In particular, we construct new extremal rays of Nef(M0,n/Sn). We also find an alternate description of all sl level 1 conformal blocks divisors on M0,n.
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تاریخ انتشار 2013