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Toral automorphisms and antiautomorphisms of rotation algebras

Published online by Cambridge University Press:  17 April 2009

Hu Yaohua
Affiliation:
School of Mathematics, La Trobe University, Bundoora Vic 3083, Australia e-mail: [email protected]
P.J. Stacey
Affiliation:
School of Mathematics, La Trobe University, Bundoora Vic 3083, Australia e-mail: [email protected]
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Abstract

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If U, V are the generators of a rational or irrational rotation C*-algebra then an automorphism φ of the algebra is determined by φ(U) = λUaVc and φ(V) = μUbVd where λ, μ are complex numbers of modulus 1 and a, b, c, d are integers with adbc = 1. If adbc = −1, then these formulae determine an antiautomorphsm of the algebra. The classification of such automorphisms and antiautomorphisms up to conjugacy by arbitrary automorphisms is studied and an almost complete classification is obtained.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1999

References

[1]Atiyah, M.F., ‘K-theory and reality’, Quart. J. Math. Oxford Ser. 2 17 (1966), 367–86.CrossRefGoogle Scholar
[2]Brenken, B., ‘Representations and automorphisms of the irrational rotation algebra’, Pacific J. Math. 111 (1984), 257282.CrossRefGoogle Scholar
[3]Farsi, C. and Watling, N., ‘Trivial fixed point subalgebras of the rotation algebra’, Math. Scand. 72 (1993), 298302.CrossRefGoogle Scholar
[4]Farsi, C. and Watling, N., ‘C*-algebras of dynamical systems on the non-commutative torus’, Math. Scand. 75 (1994), 101110.CrossRefGoogle Scholar
[5]Flath, D.E., Introduction to number theory (J. Wiley & Sons, New York, 1989).Google Scholar
[6]Karoubi, M., K-theory: an introduction (Springer-Verlag, Berlin, Heidelberg, New York, 1978).CrossRefGoogle Scholar
[7]Schröder, H., K-theory for real C*-algebras and applications, Pitman Research Notes on Mathematics 290 (Pitman, New York, 1993).Google Scholar
[8]Watatani, Y., ‘Toral automorphisms on the irrational rotation algebra’, Math. Japon. 26 (1981), 479484.Google Scholar