Operator Algebra Seminars

Fri., Feb. 17, 2017 10:45 a.m. - Fri., Feb. 17, 2017 12:00 p.m.

Location: RIC 215

Speaker: Samir Raouafi

Title: Crouzeix's Conjecture

Abstract:

Crouzeix's conjecture is an interesting open problem in operator theory. The conjecture states that the numerical range W(A) of any bounded linear operator A in a complex Hilbert space is a (complete) 2-spectral set for A. Two weeks ago, Crouzeix and Palencia proved that W(A) is (complete) 1 + sqrt(2) spectral set. We will discuss this proof and some applications.