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arXiv · 1512.06847

On the paper: Numerical radius preserving linear maps on Banach algebras

M. El Azhari
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Abstract

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.

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M. El Azhari. 2017-10-08. On the paper: Numerical radius preserving linear maps on Banach algebras. https://arxiv.org/abs/1512.06847

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