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arXiv · 0809.3644

The group of isometries of a Banach space and duality

Miguel Martin
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Abstract

We construct an example of a real Banach space whose group of surjective isometries has no uniformly continuous one-parameter semigroups, but the group of surjective isometries of its dual contains infinitely many of them. Other examples concerning numerical index, hermitian operators and dissipative operators are also shown.

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Miguel Martin. 2008-09-22. The group of isometries of a Banach space and duality. https://doi.org/10.1016/j.jfa.2008.06.004

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