On the life span of the Schrödinger equation with sub-critical power nonlinearity

Hironobu Sasaki

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arXiv · 0907.0523

On the life span of the Schrödinger equation with sub-critical power nonlinearity

Hironobu Sasaki

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Abstract

We discuss the life span of the Cauchy problem for the one-dimensional Schrödinger equation with a single power nonlinearity $λ|u|^{p-1}u$ ($λ\in\mathbb{C}$, $2\le p<3$) prescribed an initial data of the form $\varepsilonφ$. Here, $\varepsilon$ stands for the size of the data. It is not difficult to see that the life span $T(\varepsilon)$ is estimated by $C_0 \varepsilon^{-2(p-1)/(3-p)}$ from below, provided $\varepsilon$ is sufficiently small. In this paper, we consider a more precise estimate for $T(\varepsilon)$ and we prove that $\liminf_{\varepsilon\to 0}\varepsilon^{2(p-1)/(3-p)}T(\varepsilon)$ is larger than some positive constant expressed only by $p$, $\mathrm{Im}λ$ and $φ$.

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Hironobu Sasaki. 2009-07-03. On the life span of the Schrödinger equation with sub-critical power nonlinearity. https://arxiv.org/abs/0907.0523

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