Solitons: Differential equations, symmetries, and infinite-dimensional algebras
《Solitons: Differential equations, symmetries, and infinite-dimensional algebras》 · 第 304 页 · Definition 11.26(4)
A divisor $D$ is called effective if it is in the submonoid $\operatorname{Div}^+(X)=\Gamma(X,(\mathcal K_X^\times\cap\mathcal O_X)/\mathcal O_X^\times)$. In this case we write $D\geq 0$.