NEWS & EVENTS Event Calendars Event

Time & Date

9:30-12:00 AM, September 22, 2021

Venue

Room 409-411, Building 4, Yunqi Campus, Westlake University

Host

Dr. Yongqiang Zhao and Dr. Yigeng Zhao, School of Science, Westlake University

Audience

Faculty and Staff,Graduate Students,Undergraduate Students

Category

Academics and Research

Mathematics Seminar ∣Lei Song: Inner Projection and Castelnuovo-Mumford Regularity of Structure Sheaves

Time9:30-12:00 AM, September 22, 2021

Venue: Room 409-411, Building 4, Yunqi Campus, Westlake University

Host: Dr. Yongqiang Zhao and Dr. Yigeng Zhao, School of Science, Westlake University

Speaker:Prof. Lei Song, Sun Yat-sen University

TitleInner Projection and Castelnuovo-Mumford Regularity of Structure Sheaves

Abstract:

Castelnuovo-Mumford regularity in a sense measures the complexity of coherent sheaves on a projective space. A. Noma established a sharp bound for the C-M regularity of structure sheaves of smooth subvarieties. A key tool is his classification of projective subvarieties via generic inner projection. I will explain Noma's classification, and show how blending it with the positivity of double-point divisors and the theory of multiplier ideals leads to the same bound for normal projective varieties with at worst isolated, Q-Gorenstein singularities. By contrast, such a bound fails for varieties in general. This is based on a joint work with J. Moraga and J. Park.

Contact:

School of Science, Ms. Wang, wangqiuhui@westlake.edu.cn


Time & Date

9:30-12:00 AM, September 22, 2021

Venue

Room 409-411, Building 4, Yunqi Campus, Westlake University

Host

Dr. Yongqiang Zhao and Dr. Yigeng Zhao, School of Science, Westlake University

Audience

Faculty and Staff,Graduate Students,Undergraduate Students

Category

Academics and Research