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arXiv · 1006.2787

On localization of the Schrödinger maximal operator

Shuanglin Shao
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Abstract

In \cite{Lee:2006:schrod-converg}, when the spatial variable $x$ is localized, Lee observed that the Schrödinger maximal operator $e^{itΔ}f(x)$ enjoys certain localization property in $t$ for frequency localized functions. In this note, we give an alternative proof of this observation by using the method of stationary phase, and then include two applications: the first is on is on the equivalence of the local and the global Schrödinger maximal inequalities; secondly the local Schrödinger maximal inequality holds for $f\in H^{3/8+}$, which implies that $e^{itΔ}f$ converges to $f$ almost everywhere if $f\in H^{3/8+}$. These results are not new. In this note we would like to explore them from a slightly different perspective, where the analysis of the stationary phase plays an important role.

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Shuanglin Shao. 2010-06-14. On localization of the Schrödinger maximal operator. https://arxiv.org/abs/1006.2787

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