Abstract
The results of Kasparov, Connes, Higson, and Loring imply the coincidence of the functors [[qℂ ⊗ K, B ⊗ K]] = [[C 0(ℝ2) ⊗ K, B ⊗ K]] for any C*-algebra B; here[[A, B]] denotes the set of homotopy classes of asymptotic homomorphisms from A to B. Inthe paper, this assertion is strengthened; namely, it is shown that the algebras qℂ ⊗ K and C 0(ℝ2) ⊗ K are equivalent in the category whose objects are C*-algebras and morphisms are classes of homotopic asymptotic homomorphisms. Some geometric properties of the obtained equivalence are studied. Namely, the algebras qℂ ⊗ K and C 0(ℝ2) ⊗ K are represented as fields of C*-algebras; it is proved that the equivalence is not fiber-preserving, i.e., is does not take fibers to fibers. It is also proved that the algebras under consideration are not homotopy equivalent.
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REFERENCES
J. Cuntz, “A new look at KK-theory,” K-Theory, 1 (1987), no. 1, 31–51.
G. G. Kasparov, “An operator K-functor and extensions of C*-algebras,” Izv. Akad. Nauk SSSR Ser. Mat. [Math. USSR-Izv.], 44 (1980), 571–636.
A. Connes and N. Higson, “Deformations, morphismes asymptotiques et K-theorie bivariante,” C. R. Acad. Sci. Paris. Ser. I Math., 311 (1990), 101–106.
T. Loring, “Perturbation questions in the Cuntz picture of K-theory,” K-Theory, 11 (1997), 161–193.
T. Loring, “Almost multiplicative maps between C*-algebras,” in: Operator Algebras and Quantum Field Theory (Rome, 1996), Internat. Press, Cambridge, MA, 1997, pp. 111–122.
W. Arveson, “Notes on extensions of C*-algebras,” Duke Math. J., 44 (1977), 329–355.
T. Loring, “K-theory and asymptotically commuting matrices,” Canad. J. Math., 15 (1988), no. 1, 197–216.
B. Blackadar, K-Theory for Operator Algebras, Math. Sci. Res. Inst. Publ., vol. 5, Springer-Verlag, New York, 1986.
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Translated from Matematicheskie Zametki, vol. 77, no. 5, 2005, pp. 788–796.
Original Russian Text Copyright ©2005 by T. V. Shul’man.
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Shul’man, T.V. Equivalence of the C*-Algebras qℂ and C 0(ℝ2) in the Asymptotic Category. Math Notes 77, 726–734 (2005). https://doi.org/10.1007/s11006-005-0073-4
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DOI: https://doi.org/10.1007/s11006-005-0073-4