Connes proved in his beautiful paper "Compact metric spaces, Fredholm modules, and hyperfiniteness" published in 1989 that if $(A,H,D)$ is a finitely summable spectral triple with a unital $C^*$algebra $A$, then $A$ must have a tracial state. Here is the question: Is there an analogue of this result for nonunital spectral triples (for which $A$ is a nonunital $C^*$algebra and $D$ has locally compact resolvents)? What are the main obstructions for existence of finitely summable spectral triples?
