Abstract
We obtain upper and lower bounds for the Davis–Wielandt radius of bounded linear operators defined on a complex Hilbert space, which improve on the existing ones. We also obtain bounds for the Davis–Wielandt radius of operator matrices. We determine the exact value of the Davis–Wielandt radius of some special type of operator matrices.
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Acknowledgements
Mr. Pintu Bhunia would like to thank UGC, Govt. of India for the financial support in the form of SRF. Prof. Kallol Paul would like to thank RUSA 2.0, Jadavpur University for the partial support.
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Communicated by Qing-Wen Wang.
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Bhunia, P., Bhanja, A., Bag, S. et al. Bounds for the Davis–Wielandt radius of bounded linear operators. Ann. Funct. Anal. 12, 18 (2021). https://doi.org/10.1007/s43034-020-00102-9
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DOI: https://doi.org/10.1007/s43034-020-00102-9