Betterment for estimates of the numerical radii of Hilbert space operators

Document Type : Original Article

Authors

1 Department of Mathematics, Ferdows Branch, Islamic Azad University, Ferdows, Iran

2 Department of Mathematics, Payame Noor University (PNU), P.O. Box, 19395-4697, Tehran, Iran

Abstract

We give several inequalities involving numerical radii ω(⋅) and the usual operator norm ‖⋅‖ of Hilbert space operators. These inequalities lead to a considerable improvement in the well-known inequalities
12‖T‖≤ω(T)≤‖T‖.

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References

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AUT Journal of Mathematics and Computing
Volume 4, Issue 2
2023
Pages 161-167

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