Ukrainian Mathematical Journal

, Volume 55, Issue 12, pp 1994–2005 | Cite as

Factorization of Conditional Expectations on Kac Algebras and Quantum Double Coset Hypergroups

  • A. A. Kalyuzhnyi
  • Yu. A. Chapovskii


We prove that a conditional expectation on a Kac algebra, under certain conditions, decomposes into a composition of two conditional expectations of a special type and gives rise to a compact quantum hypergroup connected to a quantum Gelfand pair.


Conditional Expectation Double Coset Gelfand Pair 
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Copyright information

© Plenum Publishing Corporation 2003

Authors and Affiliations

  • A. A. Kalyuzhnyi
    • 1
  • Yu. A. Chapovskii
    • 1
  1. 1.Institute of MathematicsUkrainian Academy of SciencesKiev

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