English
Related papers

Related papers: Sharp mixed norm spherical restriction

200 papers

The purpose of this note is to discuss several results that have been obtained in the last decade in the context of sharp adjoint Fourier restriction/Strichartz inequalities. Rather than aiming at full generality, we focus on several…

Classical Analysis and ODEs · Mathematics 2017-01-25 Damiano Foschi , Diogo Oliveira e Silva

Sharp asymptotic for norms of Fourier projections on two-point homogeneous manifolds (the real sphere, the real, complex and quaternionic projective spaces and the Cayley elliptic plain) are established. These results extend sharp…

Classical Analysis and ODEs · Mathematics 2015-05-04 A. Kushpel

We dominate non-integral singular operators by adapted sparse operators and derive optimal norm estimates in weighted spaces. Our assumptions on the operators are minimal and our result applies to an array of situations, whose prototype are…

Classical Analysis and ODEs · Mathematics 2016-08-03 Frédéric Bernicot , Dorothee Frey , Stefanie Petermichl

The paper is devoted to two-weight estimates for the fractional maximal operators $\mathcal{M}^\alpha$ on general probability spaces equipped with a tree-like structure. For given $1<p\leq q<\infty$, we study the sharp universal upper bound…

Probability · Mathematics 2025-01-08 Rodrigo Bañuelos , Adam Osękowski

We prove that constant functions are the unique real-valued maximizers for all $L^2-L^{2n}$ adjoint Fourier restriction inequalities on the unit sphere $\mathbb{S}^{d-1}\subset\mathbb{R}^d$, $d\in\{3,4,5,6,7\}$, where $n\geq 3$ is an…

Classical Analysis and ODEs · Mathematics 2021-01-11 Diogo Oliveira e Silva , René Quilodrán

We find the sharp range for boundedness of the discrete bilinear spherical maximal function for dimensions $d \geq 5$. That is, we show that this operator is bounded on $l^{p}(\mathbb{Z}^d)\times l^{q}(\mathbb{Z}^d) \to l^{r}(\mathbb{Z}^d)$…

Classical Analysis and ODEs · Mathematics 2021-02-03 Theresa C. Anderson , Eyvindur Ari Palsson

We show that, for a natural class of rearrangement admissible spaces $X$ and $Y$, the Fourier operator is bounded between $X$ and $Y$ if and only if any operator of joint strong type $(1,\infty; 2,2)$ is also bounded between $X$ and $Y$. By…

Classical Analysis and ODEs · Mathematics 2025-01-30 Miquel Saucedo , Sergey Tikhonov

Let ${{\bf R}_{\mathbb{S}^{d-1}}}(p\to q)$ denote the best constant for the $L^p(\mathbb{R}^d)\to L^q(\mathbb{S}^{d-1})$ Fourier restriction inequality to the unit sphere $\mathbb{S}^{d-1}$, and let ${\bf R}_{\mathbb{S}^{d-1}} (p\to…

Classical Analysis and ODEs · Mathematics 2025-05-21 Diogo Oliveira e Silva , Błażej Wróbel

In this article we revisit some classical conjectures in harmonic analysis in the setting of mixed norm spaces $L^p_{rad} L^2_{ang} (\mathbb{R}^n)$. We produce sharp bounds for the restriction of the Fourier transform to compact…

Classical Analysis and ODEs · Mathematics 2016-01-20 Antonio Córdoba , Eric Latorre

Sharp Fourier restriction theory and finite field extension theory have both been topics of interest in the last decades. Very recently, in \cite{GonzalezOliveira}, the research into the intersection of these two topics started. There it…

Classical Analysis and ODEs · Mathematics 2025-12-01 Cristian González-Riquelme , Tolibjon Ismoilov

Quantitative formulations of Fefferman's counterexample for the ball multiplier are naturally linked to square function and vector-valued estimates for directional singular integrals. The latter are usually referred to as Meyer-type lemmas…

Classical Analysis and ODEs · Mathematics 2020-04-16 Francesco Di Plinio , Ioannis Parissis

Consider the Fourier restriction operator associated to a curve in $R^d$, $d\ge 3$. We prove for various classes of curves the endpoint restricted strong type estimate with respect to affine arclength measure on the curve. An essential…

Classical Analysis and ODEs · Mathematics 2016-04-20 Jong-Guk Bak , Daniel M. Oberlin , Andreas Seeger

We exhibit a large class of symbols $m$ on $\R^d$, $d\geq 2$, for which the corresponding Fourier multipliers $T_m$ satisfy the following inequality. If $D$, $E$ are measurable subsets of $\R^d$ with $E\subseteq D$ and $|D|<\infty$, then $$…

Probability · Mathematics 2013-06-18 Rodrigo Banuelos , Adam Osekowski

Let $\Omega$ be homogeneous of degree zero, have vanishing moment of order one on the unit sphere $\mathbb {S}^{d-1}$($d\ge 2$). In this paper, our object of investigation is the following rough non-standard singular integral operator…

Classical Analysis and ODEs · Mathematics 2022-03-11 Guoen Hu , Xiangxing Tao , Zhidan Wang , Qingying Xue

We derive refined entropy upper bounds for $q$-ary $B_2$ codes by exploiting the Fourier structure of the i.i.d. difference distribution $D=X-Y$. Since the pmf of $D$ is an autocorrelation, its Fourier series is a nonnegative trigonometric…

Information Theory · Computer Science 2026-04-01 Stefano Della Fiore

The Hausdorff-Young inequality for Euclidean space, in its sharp form due to Beckner, gives an upper bound for the Fourier transform in terms of Lebesgue space norms, with an optimal constant. The extremizers have been identified by Lieb to…

Classical Analysis and ODEs · Mathematics 2014-06-06 Michael Christ

Let $S \subset \Bbb R^n$ be a smooth compact hypersurface with a strictly positive second fundamental form, $E$ be the Fourier extension operator on $S$, and $X$ be a Lebesgue measurable subset of $\Bbb R^n$. If $X$ contains a ball of each…

Classical Analysis and ODEs · Mathematics 2023-06-22 Bassam Shayya

Suppose $0 < \alpha \leq n$, $H: \Bbb R^n \to [0,1]$ is a Lebesgue measurable function, and $A_\alpha(H)$ is the infimum of all numbers $C$ for which the inequality $\int_B H(x) dx \leq C R^\alpha$ holds for all balls $B \subset \Bbb R^n$…

Classical Analysis and ODEs · Mathematics 2022-06-14 Bassam Shayya

We give a proof of Fourier extension conjecture on the paraboloid in all dimensions bigger than 2 that begins with a decomposition suggested in Sawyer [Saw8] of writing a smooth Alpert projection as a sum of pieces whose Fourier extensions…

Classical Analysis and ODEs · Mathematics 2026-05-19 Cristian Rios , Eric T. Sawyer

In this paper, we investigate a multi-dimensional nonlocal degenerate diffusion-aggregation equation with a diffusion exponent $m$ in the intermediate range $\frac{2d}{2d-\gamma}<m<\frac{d+\gamma}{d}$, where the nonlocal aggregation term is…

Analysis of PDEs · Mathematics 2025-12-23 Tiantian Zhou , Li Chen , Yutian Lei