Time: 8h, 5/2/2021

Join Zoom Meeting:

https://zoom.us/j/94787937855?pwd=c2FiS3VGaGowUGRpcTVoenJqZW8rQT09

Meeting ID: 947 8793 7855
Passcode: 323472

Abstract: Fujita conjecture was proposed over complex numbers, which predicts that for a smooth projective variety X and an ample line bundle L on X, K_X + (dim X+1)L is base point free and K_X + nL is very ample if n > dim X+1. Joint with Yi Gu, Yongming Zhang, we find counterexamples to this elegant conjecture in positive characteristic. These examples stem from Raynaud’s surfaces. I will first report some related results on this topic and explain the construction and the proof.

For general information of the AGEA seminar, please check out

https://sites.google.com/ncts.ntu.edu.tw/agea-seminar

or the mirror site

http://www.math.ntu.edu.tw/~jkchen/agea-seminar.html