報告題目：Quasi-local algebras and asymptotic expanders
報 告 人：章嘉雯 青年副研究員 複旦大學
報告時間：2021年6月17日 13:30-14:30
報告地點：騰訊會議 ID：826 579 543密碼：0617
校内聯系人：張遠航 zhangyuanhang@jlu.edu.cn
報告摘要：Roe algebras are C*-algebras associated to metric spaces, which encode their large scale structures. These algebras play a key role in higher index theory, providing a bridge between geometry, topology and analysis. We study a quasi-local perspective on Roe algebras, which leads to a larger index algebra called the quasi-local algebra.
Based on the idea of quasi-locality, we introduce a graphic notion called asymptotic expanders which generalise the classic one of expanders. Using a structure theorem, we show that asymptotic expanders cannot be coarsely embedded into any Hilbert space and hence construct new counterexamples to the coarse Baum-Connes conjecture.
This is a joint project with Ana Khukhro, Kang Li, Piotr Nowak, Jan Spakula and Federico Vigolo.
報告人簡介：章嘉雯，複旦大學數學科學學院青年副研究員，主要從事非交換幾何領域的研究。近些年圍繞Roe代數的剛性、幾何群論的一些核心問題上取得一系列研究成果。在TAMS、JFA、Selecta Math.等重要期刊已發表多篇科研論文。
