On the Paper: Numerical Radius Preserving Linear Maps on Banach Algebras
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
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Mohammed El Azhari,
On the Paper: Numerical Radius Preserving Linear Maps on Banach Algebras, Mathematics Letters.
Vol. 3, No. 5,
2017, pp. 50-51.
Copyright © 2017 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/
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