Speaker:  Daniel Isaksen, Wayne State University

Title: Motivic Ext groups in Chow degree 1

Abstract: The Chow degree on motivic Ext groups is the stem plus the Adams filtration minus twice the motivic weight.  Every non-zero element has a non-negative Chow degree.  In Chow degree zero, the motivic Ext groups are well-understood in terms of classical Ext groups.  I will describe some recent progress on the study of motivic Ext groups in Chow degree one.  This study captures the behavior of two families of elements that were previously of interest for other reasons.  The main tool is a spectral sequence with some intriguing properties.  This project is joint work with Hana Kong, Guchuan Li, Yangyang Ruan, and Heyi Zhu.