The equivariant Milnor-Witt motive of moduli space of curves
演讲者
时间
2026年06月18日 15:00 至 16:00
地点
A6-101
线上
Zoom 518 868 7656
(BIMSA)
摘要
Grothendieck’s category of Chow motives, built from smooth projective varieties, was designed so that every Weil cohomology functor factors through it. By extending this framework to non-projective smooth varieties—via compactification and desingularization—we arrive at Voevodsky’s category of mixed motives, which provides a natural setting for motivic cohomology. Around 2020, an even more refined framework emerged: the category of Milnor-Witt motives. This category captures the quadratic information of base fields and sits much closer to the motivic stable homotopy category.
In this talk, we present a concise decomposition of the equivariant Milnor-Witt motive for the moduli space of elliptic curves with two marked points. By combining this decomposition with the work of Lorenzo and Mantovani, we can fully determine the quadratic refined intersection ring (the Chow-Witt ring) of this moduli space.
In this talk, we present a concise decomposition of the equivariant Milnor-Witt motive for the moduli space of elliptic curves with two marked points. By combining this decomposition with the work of Lorenzo and Mantovani, we can fully determine the quadratic refined intersection ring (the Chow-Witt ring) of this moduli space.
演讲者介绍
杨南君，本科毕业于北京航空航天大学，硕士博士毕业于格勒诺布尔-阿尔卑斯大学，博士导师Jean Fasel。之后在丘成桐数学科学中心做博后，现在是BIMSA的助理研究员。研究方向为代数簇的Chow-Witt群。研究成果发表在Camb. J. Math., Ann. K-Theory等期刊上。