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Numerical index of Banach spaces and duality

  • KOSTYANTYN BOYKO (a1), VLADIMIR KADETS (a1), MIGUEL MARTÍN (a2) and DIRK WERNER (a3)
Abstract

We present an example of a Banach space whose numerical index is strictly greater than the numerical index of its dual, giving a negative answer to a question which has been latent since the beginning of the seventies. We also show a particular case in which the numerical index of the space and the one of its dual coincide.

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Mathematical Proceedings of the Cambridge Philosophical Society
  • ISSN: 0305-0041
  • EISSN: 1469-8064
  • URL: /core/journals/mathematical-proceedings-of-the-cambridge-philosophical-society
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