论文标题
投影表面的限制捏点方案
Bounding Pinch Point Schemes of Projected Surfaces
论文作者
论文摘要
令$ x $为光滑的表面，让$φ：x \ to \ mathbb {p}^n $，带有$ n \ geq 4 $，为有限张的地图，它在其图像$ y =φ（x）$上均为$ y $ y $ y $ y $ y $ y $ y $ y $ nondecentore in $ \ sathbb {p}^n $。在本文中，我们为$ y $ to $ y $ to $ y $ y $ y $ y $ y $的捏合方案的长度的长度产生了下限。
Let $X$ be a smooth surface and let $φ:X\to\mathbb{P}^N$, with $N\geq 4$, be a finitely ramified map which is birational onto its image $Y = φ(X)$, with $Y$ non-degenerate in $\mathbb{P}^N$. In this paper, we produce a lower bound for the length of the pinch scheme of a general linear projection of $Y$ to $\mathbb{P}^3.$ We then prove that the lower bound is realized if and only if $Y$ is a rational normal scroll.
