题目：From cardinality to epsilon factors: geometry and categories

报告人：Fabrice Orgogozo，法国国家科学研究中心

时间：2026年6月3日（星期三）14: 00-15: 00

地点：第五教学楼5107教室

摘要：

Natural ideas from category theory lead to extensions of the cardinality of a finite set to finite groupoids and finite topological spaces. This extension —the Euler–Poincaré characteristic— also plays a fundamental role in analysis and arithmetic, appearing respectively in the Riemann–Roch theorem and in the functional equation of zeta functions.

Pushing categorification one step further leads naturally to epsilon factors. We shall give an informal introduction to them and, if time permits, discuss some more recent developments.