The Gap Metric and Internal Stability

  • Avraham Feintuch
Part of the Applied Mathematical Sciences book series (AMS, volume 130)


In Section 6.1 we saw that the internal stability of a feedback system {L, C} can be formulated in geometric terms relating the graph of L and C. In this chapter we introduce and study a precise geometric tool, the gap metric, which will allow us to study internal stability from a geometric point of view. This will prepare the grounds for a study of robust stabilization from a point of view seemingly different from that given in Chapter 8.


Orthogonal Projection Bounded Operator Feedback System Closed Operator Invertible Operator 
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References, Notes, and Remarks

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Copyright information

© Springer Science+Business Media New York 1998

Authors and Affiliations

  • Avraham Feintuch
    • 1
  1. 1.Department of Mathematics and Computer ScienceBen-Gurion University of the NegevBeer-ShevaIsrael

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