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Low regularity solutions for a 2D quadratic non-linear Schrödinger equation

Ioan Bejenaru·Daniela De Silva
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Abstract

We establish that the initial value problem for the quadratic non-linear Schrödinger equation $$ iu_t - Δu = u^2$$ where $u: \R^2 \times \R \to \C$, is locally well-posed in $H^s(\R^2)$ when $s > -1$. The critical exponent for this problem is $s_c=-1$ and previous work in \cite{c1} established local well-posedness for $s > -3/4$.

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Ioan Bejenaru, Daniela De Silva. 2006-09-08. Low regularity solutions for a 2D quadratic non-linear Schrödinger equation. https://arxiv.org/abs/math/0609241

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