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Isometric stability property of certain Banach spaces

Alexander Koldobsky
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Abstract

Let $E$ be one of the spaces $C(K)$ and $L_1$, $F$ be an arbitrary Banach space, $p>1,$ and $(X,\sigma)$ be a space with a finite measure. We prove that $E$ is isometric to a subspace of the Lebesgue-Bochner space $L_p(X;F)$ only if $E$ is isometric to a subspace of $F.$ Moreover, every isometry $T$ from $E$ into $L_p(X;F)$ has the form $Te(x)=h(x)U(x)e, e\in E,$ where $h:X\rightarrow R$ is a measurable function and, for every $x\in X,$ $U(x)$ is an isometry from $E$ to $F.$

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Alexander Koldobsky. 1993-06-09. Isometric stability property of certain Banach spaces. https://arxiv.org/abs/math/9306208

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