manuscripta mathematica

, Volume 115, Issue 2, pp 195–198 | Cite as

On the commutativity of C* -algebras

  • Jyh-Shyang JeangEmail author
  • Chun-Chieh Ko


Let Open image in new window be a C* -algebra. Let f be a non-constant complex-valued continuous function defined on a closed interval I. We shall show that f densely spans Open image in new window As an application, Open image in new window is commutative if f(x)f(y)=f(y)f(x) for all self-adjoint elements x and y in Open image in new window with spectrums contained in I.


Continuous Function Closed Interval 
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We would like to express our deep gratitude to Professor Lawrence G. Brown for several useful advices.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  1. 1.Department of Management SciencesFengshanRepublic of China
  2. 2.Department of Applied MathematicsNational Sun Yat-sen UniversityKaohsiungRepublic of China

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