Number of singular points of an annulus in $\mathbb{C}^2$
Maciej Borodzik, Henryk Zoladek
利用Bogomolov-Miyaoka-Yau不等式和一个Milnor数界，证明了$\mathbb{C}^2$中任何没有自相交的代数环$\mathbb{C}^*$最多能有三个尖点奇点.
Using Bogomolov-Miyaoka-Yau inequality and a Milnor number bound we prove that any algebraic annulus $\mathbb{C}^*$ in $\mathbb{C}^2$ with no self-intersections can have at most three cuspidal singularities.
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