Amenable and Quasidiagonality - The Tikuisis-White-Winter Theorem
A trace on a C*-algebra is amenable (resp. quasidiagonal) if it admits a net of completely positive, contractive maps into matrix algebras which approximately preserve the trace and are approximately multiplicative in the 2-norm (resp. operator norm). It is known that quasidiagonal traces are amenable. A recent result of Tikuisis, White, and Winter shows that faithful traces on separable, nuclear C*-algebras in the UCT class are quasidiagonal. In this talk, I will discuss this result and a new proof of this result which avoids many of the classification and regularity techniques used in the original proof.