We prove that a general complete intersection of dimension n, codimension c and type d1, . . . , dc in PN has ample cotangent bundle if c ≥ 2n − 2 and the degrees di are all greater than a bound that is O(1) in N and quadratic in n. This degree bound substantially improves the currently best-known super-exponential bound in N by Deng, although our result does not address the case n ≤ c < 2n − 2.
Funding
RTG: Algebraic and Arithmetic Geometry at the Univertsity of Illinois at Chicago | Funder: National Science Foundation | Grant ID: DMS-1246844
Birational Geometry of Moduli Spaces and Bridgeland Stability | Funder: National Science Foundation | Grant ID: DMS-1500031
FRG: Collaborative Research: Bridgeland Stability, Moduli Spaces and Birational Geometry | Funder: National Science Foundation | Grant ID: DMS-1664296
History
Citation
Coskun, I.Riedl, E. (2020). Effective bounds on ampleness of cotangent bundles. Bulletin of the London Mathematical Society, 52(1), 237-243. https://doi.org/10.1112/blms.12322