Pseudoconformal Transformation

The pseudoconformal transformation

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maps solutions of the mass critical NLS to solutions. The pseudoconformal image of a soliton is an explicit blowup solution. The pseudoconformal transformation is an isometry on $L_{x}^{2}$ and on $L^{2}$-admissible Strichartz spaces $L_{\tau }^{q}L_{y}^{r}$.