Almost Commuting Matrices

Document Type

Presentation Abstract

Presentation Date

11-18-2019

Abstract

Suppose that A and B are square matrices of the same size that do not commute, but almost commute. That is, AB and BA are not equal but close to equal. To what extent can A and B be approximated by matrices that commute exactly? We will survey a variety of known results to variations of this problem, both positive and negative. Much of the discussion will be elementary, but we will also draw connections to the winding number of the punctured plane and to lifting problems for C*-algebras and K-theory obstructions.

Additional Details

Monday, November 18, 2019 at 3:00 p.m. in Math 103
Refreshments at 4:00 p.m. in Math Lounge 109

This document is currently not available here.

Share

COinS