Bounding pinch point schemes of projected surfaces
Abstract
Let X be a smooth surface and let π : π β β π , with π β₯ 4 , be a finitely ramified map which is birational onto its image π = π β‘ ( π ) , with Y non-degenerate in β π . In this paper, we produce a lower bound for the length of the pinch point scheme of a general linear projection of Y to β 3 . We then prove that the lower bound is realized if and only if Y is a rational normal scroll.
Fields of Study & Subjects
Computational Geometry and Mesh Generation
Mathematics and Applications
Advanced Numerical Analysis Techniques
Publication details
- Journal / source
- Journal of Pure and Applied Algebra
- Volume
- 230
- Issue
- 11
- Pages
- 108381β108381
- Publication date
- 28 August 2026
- Language
- EN