3 problems

Let ${\overline{\mathnormal{M}}}_{0,N}$ be the moduli space of stable $N$-pointed genus-zero curves. An $F$-divisor is a divisor that nonnegatively intersects every $F$-curve; let…

Let ${\overline{\mathnormal{M}}}_{g,n}$ be the moduli space of stable $n$-pointed curves of genus $g$. Its $F$-curves are the numerical classes of curves arising as one-dimensional…

Let $\overline M_{0,n}$ be the moduli space of stable genus-zero curves with $n$ marked points. A divisor is F-nef if it intersects non-negatively with all one-dimensional boundary…