The complete classification of unital graph $C^*$-algebras: Geometric and strong

Autor: Eilers, Søren, Restorff, Gunnar, Ruiz, Efren, Sørensen, Adam P. W.
Rok vydání: 2016
Předmět:
Zdroj: Duke Math. J. Vol. 170 (2021), no. 11, pp. 2421-2517
Druh dokumentu: Working Paper
DOI: 10.1215/00127094-2021-0060
Popis: We provide a complete classification of the class of unital graph $C^*$-algebras - prominently containing the full family of Cuntz-Krieger algebras - showing that Morita equivalence in this case is determined by ordered, filtered $K$-theory. The classification result is geometric in the sense that it establishes that any Morita equivalence between $C^*(E)$ and $C^*(F)$ in this class can be realized by a sequence of moves leading from $E$ to $F$, in a way resembling the role of Reidemeister moves on knots. As a key ingredient, we introduce a new class of such moves, establish that they leave the graph algebras invariant, and prove that after this augmentation, the list of moves becomes complete in the sense described above. Along the way, we prove that every ordered, reduced filtered $K$-theory isomorphism can be lifted to an isomorphism between the stabilized $C^*$-algebras - and, as a consequence, that every ordered, reduced filtered $K$-theory isomorphism preserving the class of the unit comes from a $*$-isomorphism between the unital graph $C^*$-algebras themselves. It follows that the question of Morita equivalence amongst unital graph $C^*$-algebras is a decidable one. As immediate examples of applications of our results we revisit the classification problem for quantum lens spaces and verify, in the unital case, the Abrams-Tomforde conjectures.
Comment: This article draws heavily on results and notation developed in arXiv:1602.03709, arXiv:1604.05439 and arXiv:1605.06153, and together with these papers supersedes the results of arXiv:1505.06773, which will not be published. The second version adjusts the proof of decidability in Section 14.2 to the appeared version of [BS18], corrects the statement of Corollary 3.6, and updates references
Databáze: arXiv