论文标题
曲线模量空间的非多层有效锥
Non-polyhedral effective cones from the moduli space of curves
论文作者
论文摘要
We show that the pseudoeffective cone of divisors $\overline{\text{Eff}}^1(\overline{\mathcal{M}}_{g,n})$ for $g\geq 2$ and $n\geq 2$ is not polyhedral by showing that the class of the fibre of the morphism forgetting one point forms an extremal ray of the dual nef曲线的圆锥$ \叠加{\ text {nef}} _ 1（\ overline {\ mathcal {m}} _ {g，n}）$，此射线上的锥体不是多面的。
We show that the pseudoeffective cone of divisors $\overline{\text{Eff}}^1(\overline{\mathcal{M}}_{g,n})$ for $g\geq 2$ and $n\geq 2$ is not polyhedral by showing that the class of the fibre of the morphism forgetting one point forms an extremal ray of the dual nef cone of curves $\overline{\text{Nef}}_1(\overline{\mathcal{M}}_{g,n})$ and the cone at this ray is not polyhedral.
