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arXiv · 1911.12262

Discrete restriction for $(x,x^3)$ and related topics

Kevin Hughes·Trevor D. Wooley
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Abstract

Defining the truncated extension operator $E$ for a sequence $a(n)$ with $n \in {\mathbb Z}$ by putting \[ E{a}(\alpha,\beta):=\sum_{|n|\leq N}a(n) e(\alpha n^3 + \beta n), \] we obtain the conjectured tenth moment estimate \[ \| E{a} \|_{L^{10}({\mathbb T}^2)}\lesssim_\epsilon N^{\frac{1}{10}+\epsilon} \|a\|_{\ell^2({\mathbb Z})}. \] We obtain related conclusions when the curve $(x,x^3)$ is replaced by $(\phi_1(x), \phi_2(x))$ for suitably independent polynomials $\phi_1(x),\phi_2(x)$ having integer coefficients.

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Kevin Hughes, Trevor D. Wooley. 2019-11-27. Discrete restriction for $(x,x^3)$ and related topics. https://arxiv.org/abs/1911.12262

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