A note on the mapping theorem of essential pseudospectra on a Banach space

  • Aymen Ammar Department of Mathematics, University of Sfax, Tunisia
  • S. Veeramani Department of Mathematics, Vellore Institute of Technology, Tamil Nadu, India
Keywords: Essential spectrum, essential pseudospectrum, mapping theorem


UDC 517.98

The main goal  of the paper is to determine some basic properties of the essential pseudospectrum of a bounded linear operator $A$ defined on a Banach space $X.$ We also  prove two different versions of the essential pseudospectral mapping theorem.


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How to Cite
Ammar, A., and S. Veeramani. “A Note on the Mapping Theorem of Essential Pseudospectra on a Banach Space”. Ukrains’kyi Matematychnyi Zhurnal, Vol. 76, no. 3, Mar. 2024, pp. 341 -52, doi:10.3842/umzh.v76i3.7325.
Research articles