Extension of the ν-metric: the H Case

  • Joseph A. BallEmail author
  • Amol J. Sasane
Conference paper
Part of the Operator Theory: Advances and Applications book series (OT, volume 221)


An abstract ν-metric was introduced by Ball and Sasane, with a view towards extending the classical ν-metric of Vinnicombe from the case of rational transfer functions to more general nonrational transfer function classes of infinite-dimensional linear control systems.In this short note, we give an additional concrete special instance of the abstract ν-metric, by verifying all the assumptions demanded in the abstract set-up.T his example links the abstract ν-metric with the one proposed by Vinnicombe as a candidate for the ν-metric for nonrational plants.


ν-metric robust control Hardy algebra quasianalytic functions 


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Copyright information

© Springer Basel 2012

Authors and Affiliations

  1. 1.Department of MathematicsVirginia TechBlacksburgUSA
  2. 2.Department of MathematicsRoyal Institute of TechnologyStockholmSweden

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