Commutant Lifting

  • Donald Sarason
Part of the Operator Theory Advances and Applications book series (OT, volume 207)


This article is the story of how the author had the good fortune to be able to prove the primordial version of the commutant lifting theorem. The phrase “good fortune” is used advisedly. The story begins with the intersection of two lives, Paul’s and the author’s.

Mathematics Subject Classification (2000)

Primary 47A20 47A45 Secondary 47A15 30D55 


Commutant lifting unitary dilation operator models Hardy spaces 


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© Springer Basel AG 2010

Authors and Affiliations

  • Donald Sarason
    • 1
  1. 1.Department of MathematicsUniversity of CaliforniaBerkeleyUSA

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