On the Davis-Wielandt shell of an operator and the Davis-Wielandt index of a normed linear space

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چکیده

We study the Davis-Wielandt shell and radius of an operator on a normed linear space $$\mathcal {X}$$ . show that after suitable modification, modified defines norm {L}(\mathcal {X})$$ which is equivalent to usual introduce index compute its value explicitly in case some particular polyhedral Banach spaces. also present general method estimate any finite-dimensional space.

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ژورنال

عنوان ژورنال: Collectanea Mathematica

سال: 2021

ISSN: ['2038-4815', '0010-0757']

DOI: https://doi.org/10.1007/s13348-021-00332-7