The undecidability of having the QWEP (2205.07102v2)

Abstract: We show that neither the class of C*-algebras with Kirchberg's QWEP property nor the class of W*-probability spaces with the QWEP property are effectively axiomatizable (in the appropriate languages). The latter result follows from a more general result, namely that the hyperfinite III$1$ factor does not have a computable universal theory in the language of W*-probability spaces. We also prove that the Powers' factors $\mathcal{R}\lambda$, for $0<\lambda<1$, when equipped with their canonical Powers' states, do not have computable universal theory.