Reflexivity and sets of Fréchet subdifferentiability

Kurka, Ondřej

doi:10.1090/S0002-9939-08-09425-2

Reflexivity and sets of Fréchet subdifferentiability
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by Ondřej Kurka

Proc. Amer. Math. Soc. 136 (2008), 4467-4473

DOI: https://doi.org/10.1090/S0002-9939-08-09425-2

Published electronically: June 17, 2008

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Abstract:

We show that the sets of Fréchet subdifferentiability of Lipschitz functions on a Banach space $X$ are Borel if and only if $X$ is reflexive. This answers a question of L. Zajíček.

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