The Group of Unital C*-extensions

  • Vladimir Manuilov
  • Klaus Thomsen
Part of the Trends in Mathematics book series (TM)


Let A and B be separable C*-algebras, A unital and B stable. It is shown that there is a natural six-terms exact sequence which relates the group which arises by considering all semi-split extensions of A by B to the group which arises by restricting the attention to unital semi-split extensions of A by B. The six-terms exact sequence is an unpublished result of G. Skandalis.


C*-algebra extension unital extension absorbing homomorphism 


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Copyright information

© Birkhäuser Verlag Basel/Switzerland 2006

Authors and Affiliations

  • Vladimir Manuilov
    • 1
  • Klaus Thomsen
    • 2
  1. 1.Dept. of Mechanics and MathematicsMoscow State UniversityMoscowRussia
  2. 2.Department of Mathematics Ny MunkegadeIMFAarhus CDenmark

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