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arXiv · 1011.0212

Continuity of Translation Operators

Krishna B. Athreya·Justin R. Peters
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Abstract

For a Radon measure $\mu$ on $\bbR,$ we show that $L^{\infty}(\mu)$ is invariant under the group of translation operators $T_t(f)(x) = {$f(x-t)$}\ (t \in \bbR)$ if and only if $\mu$ is equivalent to Lebesgue measure $m$. We also give necessary and sufficient conditions for $L^p(\mu),\1 \leq p < \infty,$ to be invariant under the group $\{T_t\}$ in terms of the Radon-Nikodym derivative w.r.t. $m$.

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Krishna B. Athreya, Justin R. Peters. 2010-10-31. Continuity of Translation Operators. https://arxiv.org/abs/1011.0212

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