Relative Bogomolov’s Inequality
نویسنده
چکیده
is a pseudo-effective divisor on Y . We have an application to a problem concerning the positivity of divisors on the moduli space of stable curves, namely, let Mg (resp. Mg) be the moduli space of stable (resp. smooth) curves of genus g ≥ 2. Let λ be the Hodge class and δi’s (i = 0, . . . , [g/2]) are boundary classes. Then, a divisor (8g+4)λ− gδ0− ∑[g/2] i=1 4i(g− i)δi is pseudo-effective, and numerically effective on Mg, i.e., the intersection number with any curves passing through Mg is non-negative.
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