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A remark on the freeness condition of Suzuki’s correspondence theorem for intermediate \(C^*\)-algebras. (English) Zbl 1483.46058

Summary: Let \(\Gamma\) be a discrete group satisfying the approximation property (AP). Let \(X, Y\) be \(\Gamma \)-spaces and \(\pi : Y \to X\) be a proper factor map which is injective on the non-free part. We prove the one-to-one correspondence between intermediate \(\mathrm{C}^*\)-algebras of \(C_0(X) \rtimes_r \Gamma \subset C_0(Y) \rtimes_r \Gamma\) and intermediate \(\Gamma\)-\(\mathrm{C}^\ast \)-algebras of \(C_0(X) \subset C_0(Y)\). This is a generalization of Suzuki’s theorem that proves the statement for free actions.

MSC:

46L05 General theory of \(C^*\)-algebras

References:

[1] For every distinct elements s, t ∈ T , one has C Γ (s) ∩ {t, t −1 } = ∅.
[2] |{C F d (t) | t ∈ T }| < ∞.
[3] Brown N. P. and Ozawa N., C * -algebras and finite-dimensional approx-imations, volume 88. American Mathematical Soc., 2008. · Zbl 1160.46001
[4] Engelking R., Dimension theory, North-Holland Publishing Company Amsterdam, 1978. · Zbl 0401.54029
[5] Ge L. and Kadison R., On tensor products of von Neumann algebras. Inventiones mathematicae 123 (1996), 453-466. · Zbl 0902.46037
[6] Haagerup U. and Kraus J., Approximation properties for group C * -algebras and group von Neumann algebras. Transactions of the American Mathematical Society 344 (1994), 667-699. · Zbl 0806.43002
[7] Izumi M., Longo R. and Popa S., A Galois correspondence for compact groups of automorphisms of von Neumann algebras with a generalization to Kac algebras. Journal of Functional Analysis 155 (1998), 25-63. · Zbl 0915.46051
[8] Izumi M., Inclusions of simple C * -algebras. J. reine angew. Math. 547 (2002), 97-138. · Zbl 1007.46048
[9] Kapovich I. and Benakli N., Boundaries of hyperbolic groups. In Com-binatorial and geometric group theory (New York, 2000/Hoboken, NJ, 2001), volume 296 of Contemp. Math., pages 39-93. Amer. Math. Soc., Providence, RI, 2002. · Zbl 1044.20028
[10] Lance E. C., Hilbert C * -modules: a toolkit for operator algebraists, vol-ume 210. Cambridge University Press, 1995. · Zbl 0822.46080
[11] Suzuki Y., Group C * -algebras as decreasing intersection of nuclear C * -algebras. American Journal of Mathematics 139 (2017), 681-705. · Zbl 1390.46052
[12] Suzuki Y., Complete descriptions of intermediate operator algebras by intermediate extensions of dynamical systems, arXiv preprint arXiv: 1805.02077, 2018.
[13] Whitehead J. H. C., Note on a theorem due to Borsuk. Bulletin of the American Mathematical Society 54 (1948), 1125-1132. · Zbl 0041.31901
[14] Zacharias J., Splitting for subalgebras of tensor products. Proceedings of the American Mathematical Society 129 (2001), 407-413. · Zbl 0983.46043
[15] Zsidó L., A criterion for splitting C * -algebras in tensor products. Pro-ceedings of the American Mathematical Society 128 (2000), 2001-2006. · Zbl 0947.46038
[16] Ryo Ochi E-mail: ochi.ryo.55x@kyoto-u.jp
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