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arXiv · 2611.03527

Critical orthonormal Strichartz estimates for Lebesgue spaces

Yinghao Gong
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Abstract

We study orthonormal Strichartz estimates at the critical coefficient exponent $q/2$ for fractional Schrödinger propagators. The proof for $d\geq3$ combines annular Schatten estimates with a frequency summation argument based on potential duality and Littlewood--Paley theory. In dimension two, a trace computation supplies the annular estimate needed for the global estimate. We also construct a counterexample to the global estimate with spatial $L^\infty$ and coefficients in $\ell^{q/2}$, even with a weak time norm.

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Yinghao Gong. 2026-11-02. Critical orthonormal Strichartz estimates for Lebesgue spaces. https://arxiv.org/abs/2611.03527

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