An alternative estimate for the numerical radius of Hilbert space operators
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Mohsen Shah Hosseini
Abstract
We give an alternative lower bound for the numerical radii of Hilbert space operators. As a by-product, we find conditions such that
where R, S ∈ 𝔹(𝓗).
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Communicated by Michal Zajac
Acknowledgement
The authors would like to thank an anonymous referee for pointing out a crucial mistake in Theorem 2.1.
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© 2020 Mathematical Institute Slovak Academy of Sciences
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Articles in the same Issue
- Regular papers
- Doc. RNDr. Roman Frič, DrSc. – 3/4 C?
- Sugihara algebras and Sugihara monoids: Multisorted dualities
- Two by two squares in set partitions
- Identifying quantum logics by numerical events
- Some remarks on divisible polyhedral MV-algebras
- Remarks on b-metrics, ultrametrics, and metric-preserving functions
- Estimates of essential norm of generalized weighted composition operators from Bloch type spaces to nth weighted type spaces
- Maximum term of transcendental entire function and spider’s web
- Entire solutions of certain type of non-linear differential equations
- On the oscillatory behavior of third order differential equations with a sublinear neutral term
- Eigenvalue problems for a class of nonlinear Hadamard fractional differential equations with p-Laplacian operator
-
The amalgam space
- On the topology of partial metric spaces
- The trace of the commutator of the Cesàro operator and a compact operator
- Yamabe soliton and quasi Yamabe soliton on Kenmotsu manifold
- On 4-th root metrics of isotropic scalar curvature
- On ultrametric-preserving functions
- Porosity of 𝓢-approximately continuous functions
- On a modified Burr XII distribution having flexible hazard rate shapes
- A study of chi-square-type distribution with geometrically distributed degrees of freedom in relation to distributions of geometric random sums
- An alternative estimate for the numerical radius of Hilbert space operators
