报告1：吴华伟学术报告

Title: Unconditionally Secure Non-malleable Secret Sharing and Circular External Difference Families

时间：1月29日 上午9:00-10:00

地点:145报告厅

报告人简介： 吴华伟，清华大学博士.

Abstract: The circular external difference family and its strong version, which themselves are of independent combinatorial interest, were proposed as variants of the difference family to construct new unconditionally secure non-malleable threshold schemes. In this talk, we present new results regarding the construction and non-existence of (strong) circular external difference families, thereby solving several open problems on this topic.

报告2： 阳恩林学术报告

时间：1月29日 上午10:00-11:00

地点:145报告厅

Title: Characteristic classes in etale cohomology

Abstract: In this talk, we will sketch the construction of non-acyclicity classes for constructible sheaves on varieties, which is defined in a recent joint work with Yigeng Zhao. This cohomological class is supported on the non-locally acyclic locus. As applications, we show that the Milnor formula and Bloch’s conductor formula can be reformulated in terms of the functorial properties of non-acyclicity classes.

报告人简介：阳恩林，北京大学数学科学学院助理教授，博士生导师。他于2010年获清华大学学士学位，2015年获清华大学博士学位，2015年至2018年在柏林自由大学与雷根斯堡大学从事博士后研究。主要研究方向为算术几何、数论与几何分歧。