Abstract
We construct a bounded linear operator on a separable, reflexive and strictly convex Banach space with the resolvent norm that is constant in a neighbourhood of zero.
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Shargorodsky, E., Shkarin, S. The level sets of the resolvent norm and convexity properties of Banach spaces. Arch. Math. 93, 59–66 (2009). https://doi.org/10.1007/s00013-009-0001-z
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DOI: https://doi.org/10.1007/s00013-009-0001-z