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arXiv · 0906.2989

Smooth extensions of functions on separable Banach spaces

D. Azagra·R. Fry·L. Keener
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Abstract

Let $X$ be a Banach space with a separable dual $X^{*}$. Let $Y\subset X$ be a closed subspace, and $f:Y\to\mathbb{R}$ a $C^{1}$-smooth function. Then we show there is a $C^{1}$ extension of $f$ to $X$.

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D. Azagra, R. Fry, L. Keener. 2009-06-16. Smooth extensions of functions on separable Banach spaces. https://arxiv.org/abs/0906.2989

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