On the Paper: Numerical Radius Preserving Linear Maps on Banach Algebras
Mathematics Letters
Volume 3, Issue 5, October 2017, Pages: 50-51
Received: May 16, 2017; Accepted: Sep. 8, 2017; Published: Oct. 10, 2017
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Mohammed El Azhari, Department of Mathematics, Ecole Normale Supérieure, Rabat, Morocco
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We give an example of a unital commutative complex Banach algebra having a normalized state which is not a spectral state and admitting an extreme normalized state which is not multiplicative. This disproves two results by Golfarshchi and Khalilzadeh.
Banach Algebra, Regular Norm, Normalized State, Spectral State
To cite this article
Mohammed El Azhari, On the Paper: Numerical Radius Preserving Linear Maps on Banach Algebras, Mathematics Letters. Vol. 3, No. 5, 2017, pp. 50-51. doi: 10.11648/j.ml.20170305.11
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This article is an open access article distributed under the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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