"Length for C*-algebras: an introduction"

Synopsis:  Gilles Pisier introduced the concept of length for general operator
algebras, and showed that an operator algebra A has finite length if, and only
if, there is a positive solution to the similarity problem for the algebra A.
This talk will concentrate on length for C*-algebras and von Neumann algebras
with the basic definitions, some examples and an attempt to explain the
intuition behind the idea.