On the Joint Numerical Spectrum in Banach Spaces

Original Paper


The purpose of this paper is to introduce the joint numerical spectrum of a q tuple of operators on a Banach space and to study its properties. This notion generalizes both the joint numerical range and the numerical spectrum.


Numerical spectrum Joint spectrum Joint numerical range 

Mathematics Subject Classification

Primary 47A10 Secondary 47A12 



The authors wish to thank the anonymous referees for their careful reading of the manuscript.


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Copyright information

© Iranian Mathematical Society 2018

Authors and Affiliations

  1. 1.Department of Mathematics, Faculty of Sciences of SfaxUniversity of SfaxSfaxTunisia
  2. 2.Mathematisches InstitutUniversität LeipzigLeipzigGermany

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