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Related papers: A contractive Hardy-Littlewood inequality

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We give a direct proof of the operator valued Hardy-Littlewood maximal inequality for $2<p<\infty$.

Functional Analysis · Mathematics 2024-09-04 ChianYeong Chuah , Zhenchuan Liu , Tao Mei

We prove the Hardy-Littlewood theorem in two dimensions for functions whose Fourier coefficients obey general monotonicity conditions and, importantly, are not necessarily positive. The sharpness of the result is given by a counterexample,…

Classical Analysis and ODEs · Mathematics 2023-10-06 Kristina Oganesyan

For $p\in (1,\infty)$ and $\alpha\in\mathbb{R}$, we consider measurable functions $g$ on $\mathbb{S}^{N-1}$ that satisfy the following weighted Hardy inequality: \begin{equation}\label{abs} \int_{\mathbb{R}^N}\frac{ g…

Analysis of PDEs · Mathematics 2026-03-26 Subhajit Roy

This is the first in our series of papers concerning some Hardy-Littlewood-Sobolev type inequalities. In the present paper, the main objective is to establish the following sharp reversed HLS inequality in the whole space $\mathbb R^n$…

Analysis of PDEs · Mathematics 2018-08-31 Quôc-Anh Ngô , Van Hoang Nguyen

The classical sharp Hardy-Littlewood-Sobolev inequality states that, for $1<p, t<\infty$ and $0<\lambda=n-\alpha <n$ with $ 1/p +1 /t+ \lambda /n=2$, there is a best constant $N(n,\lambda,p)>0$, such that $$ |\int_{\mathbb{R}^n}…

Analysis of PDEs · Mathematics 2014-07-11 Jingbo Dou , Meijun Zhu

Hardy's inequality on $H^p$ spaces, $p\in(0,1]$, in the context of orthogonal expansions is investigated for general basis on a subset of $\mathbb{R}^d$ with Lebesgue measure. The obtained result is applied to various Hermite, Laguerre, and…

Classical Analysis and ODEs · Mathematics 2020-05-15 Paweł Plewa

We obtain sharp two-sided inequalities between $L^p-$norms $(1<p<\infty)$ of functions $Hf$ and $H^*f$, where $H$ is the Hardy operator, $H^*$ is its dual, and $f$ is a nonnegative measurable function on $(0,\infty).$ In an equivalent form,…

Classical Analysis and ODEs · Mathematics 2012-06-11 Viktor Kolyada

We prove some Hardy type inequalities related to quasilinear second order degenerate elliptic differential operators L_p(u):=-\nabla_L^*(\abs{\nabla_L u}^{p-2}\nabla_L u). If \phi is a positive weight such that -L_p\phi>= 0, then the Hardy…

Analysis of PDEs · Mathematics 2007-05-23 Lorenzo D'Ambrosio

We establishe an affine Hardy-Littlewood-Sobolev inequality concerning two different functions which is stronger than the classical Hardy-Littlewood-Sobolev inequality. Furthermore, we also prove reverse inequalities for the new…

Functional Analysis · Mathematics 2025-08-05 Youjiang Lin , Jinghong Zhou , Jiaming Lan

The Hardy-Littlewood inequality on $\mathbb{T}$ compares the $L^p$-norm of a function with a weighted $\ell^p$-norm of its Fourier coefficients. The approach has recently been studied for compact homogeneous spaces and we study a natural…

Operator Algebras · Mathematics 2018-03-16 SangGyun Youn

We prove an appropriate sharp quantitative reverse H\"older inequality for the $C_p$ class of weights from which we obtain as a limiting case the sharp reverse H\"older inequality for the $A_\infty$ class of weights. We use this result to…

Classical Analysis and ODEs · Mathematics 2020-06-17 Javier Canto

We prove sharp inequalities of Hardy type for functions in the Sobolev space $W^{1,p}$ on the unit sphere $\mathbb{S}^{n-1}$ in $\mathbb{R}^{n}$. We achieve this in both the subcritical and critical cases. The method we use to show…

Functional Analysis · Mathematics 2020-06-15 Ahmed A. Abdelhakim

We prove the self-improvement of a pointwise $p$-Hardy inequality. The proof relies on maximal function techniques and a characterization of the inequality by curves.

Classical Analysis and ODEs · Mathematics 2018-10-18 Sylvester Eriksson-Bique , Antti V. Vähäkangas

We improve the classical discrete Hardy inequality for $ 1<p<\infty $ for functions on the natural numbers. For integer values of $ p $ the Hardy weight is an absolutely monotonic function.

Classical Analysis and ODEs · Mathematics 2019-10-09 Florian Fischer , Matthias Keller , Felix Pogorzelski

We state and discuss several interrelated results, conjectures, and questions regarding contractive inequalities for classical $H^p$ spaces of the unit disc. We study both coefficient estimates in terms of weighted $\ell^2$ sums and the…

Functional Analysis · Mathematics 2018-12-05 Ole Fredrik Brevig , Joaquim Ortega-Cerdà , Kristian Seip , Jing Zhao

We consider functions L_p-integrable with Jacobi weights on [-1,1] and prove Hardy--Littlewood type inequalities for fractional integrals. As applications, we obtain the sharp (L_p, L_q) Ulyanov-type inequalities for the Ditzian--Totik…

Functional Analysis · Mathematics 2016-01-06 Polina Glazyrina , Sergey Tikhonov

In this article we present a new proof of a sharp Reverse H\"older Inequality for $A_\infty$ weights that is valid in the context of spaces of homogeneous type. Then we derive two applications: a precise open property of Muckenhoupt classes…

Classical Analysis and ODEs · Mathematics 2012-08-21 Tuomas Hytönen , Carlos Pérez , Ezequiel Rela

In this paper we prove sharp multipolar Hardy-type inequalities in the Riemannian $L^p-$setting for $p\geq 2$ using the method of super-solutions and fundamental results from comparison theory on manifolds, thus generalizing previous…

Analysis of PDEs · Mathematics 2025-03-07 Cristian Ciulică , Teodor Rugină

We prove a generalization of a Hardy type inequality for negative exponents valid for non-negative functions defined on $(0,1]$. As an application we find the exact best possible range of $p$ such that $1<p\le q$ such that any…

Functional Analysis · Mathematics 2014-05-06 Eleftherios N. Nikolidakis

There are at least two directions concerning the extension of classical sharp Hardy-Littlewood-Sobolev inequality: (1) Extending the sharp inequality on general manifolds; (2) Extending it for the negative exponent $\lambda=n-\alpha$ (that…

Analysis of PDEs · Mathematics 2013-09-11 Jingbo Dou , Meijun Zhu
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