Abstract
In this work, we study non-rough norms in L(X, Y), the space of bounded linear operators between Banach spaces X and Y. We prove that L(X, Y) has non-rough norm if and only if \(X^*\) and Y have non-rough norm. We show that the injective tensor product \(X{\hat{\otimes }}_{\varepsilon } Y\) has non-rough norm if and only if both X and Y have non-rough norm. We also give an example to show that non-rough norms are not stable under projective tensor product. We also study a related concept namely the small diameter properties in the context of \(L(X,Y)^*\). These results lead to a discussion on stability of the small diameter properties for projective and injective tensor product spaces.
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Acknowledgements
We are grateful to the referee for going through our work meticulously and making significant comments. The first author’s research is supported by the dean’s supplemental fund provided by the College of Arts and Sciences, Loyola University, Maryland, USA. The third author’s research is funded by the National Board for Higher Mathematics (NBHM), Department of Atomic Energy (DAE), Government of India, Ref No. 0203/11/2019-R &D-II/9249.
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Basu, S., Guerrero, J.B., Seal, S. et al. Non-rough Norms and Dentability in Spaces of Operators. Mediterr. J. Math. 20, 338 (2023). https://doi.org/10.1007/s00009-023-02519-7
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DOI: https://doi.org/10.1007/s00009-023-02519-7