English
Related papers

Related papers: The two-weight Hardy inequality: a new elementary …

200 papers

We develop a new proof of the result of L.-E.~Persson and V.D.~Stepanov \cite[Theorems 1 and 3]{Per:02}, which provides a characterization of a Hardy integral inequality involving two weights, and which can be applied to an effective…

Functional Analysis · Mathematics 2025-07-02 Amiran Gogatishvili , Luboš Pick , Hana Turčinová , Tuğçe Ünver

Let $U:[0,\infty)^2 \to [0,\infty)$ be a~measurable kernel satisfying: (i) $U(x,y)$ is nonincreasing in $x$ and nondecreasing in $y$; (ii) there exists a~constant $\theta>0$ such that $U(x,z) \le \theta\left( U(x,y)+U(y,z) \right)$ for all…

Functional Analysis · Mathematics 2016-02-03 Martin Křepela

Some q-analysis variants of Hardy type inequalities of the form \int_0^b (x^{\alpha-1} \int_0^x t^{-\alpha} f(t) d_qt)^p d_qx \leq C \int_0^b f^p(t) d_qt with sharp constant C are proved and discussed. A similar result with the…

Classical Analysis and ODEs · Mathematics 2014-03-26 Lech Maligranda , Ryskul Oinarov , Lars-Erik Persson

We study the two-weighted estimate \[ \bigg\|\sum_{k=0}^na_k(x)\int_0^xt^kf(t)dt|L_{q,v}(0,\infty)\bigg\|\leq c\|f|L_{p,u}(0,\infty)\|,\tag{$*$} \] where the functions $a_k(x)$ are not assumed to be positive. It is shown that for $1<p\leq…

Classical Analysis and ODEs · Mathematics 2021-06-25 Vyacheslav S. Rychkov

In a note published in 1925, G. H. Hardy stated the inequality \begin{equation*} \sum_{n=1}^\infty \left(\frac{1}{n}\sum_{k=1}^n a_k \right)^p \leq \left(\frac{p}{p-1}\right)^p \sum_{n=1}^\infty a_n^p, \end{equation*} for any non-negative…

Analysis of PDEs · Mathematics 2020-02-20 Giao Bui , Fernando López-García , Van Tran

We study a three-weight inequality for the superposition of the Hardy operator and the Copson operator, namely \begin{equation*} \bigg(\int_a^b \bigg(\int_t^b \bigg(\int_a^s f(\tau)^p v(\tau) \,d\tau \bigg)^\frac{q}{p} u(s) \,ds…

Functional Analysis · Mathematics 2022-05-17 Amiran Gogatishvili , Zdeněk Mihula , Luboš Pick , Hana Turčinová , Tuğçe Ünver

New proofs of the classical Hermite-Hadamard inequality are presented and several applications are given, including Hadamard-type inequalities for the functions, whose derivatives have inflection points or whose derivatives are convex.…

General Mathematics · Mathematics 2020-10-14 Ilham A. Aliev , Mehmet E. Tamar , Cagla Sekin

In this note we continue giving the characterisation of weights for two-weight Hardy inequalities to hold on general metric measure spaces possessing polar decompositions. Since there may be no differentiable structure on such spaces, the…

Functional Analysis · Mathematics 2021-07-14 Michael Ruzhansky , Daulti Verma

We present an easy proof that $p$--Hardy's inequality implies uniform $p$--fatness of the boundary when $p=n$. The proof works also in metric space setting and demonstrates the self--improving phenomenon of the $p$--fatness. We also explore…

Functional Analysis · Mathematics 2010-03-18 Riikka Korte , Nageswari Shanmugalingam

We investigate the weighted fractional order Hardy inequality $$ \int_{\Omega}\int_{\Omega}\frac{|f(x)-f(y)|^{p}}{|x-y|^{d+sp}}\text{dist}(x,\partial\Omega)^{-\alpha}\text{dist}(y,\partial\Omega)^{-\beta}\,dy\,dx\geq…

Analysis of PDEs · Mathematics 2026-01-05 Bartłomiej Dyda , Michał Kijaczko

Motivated by previous work leveraging factorizations of second- and fourth-order differential operators, a general integral inequality involving higher order derivatives is proven by elementary means. It is then shown how this framework…

Classical Analysis and ODEs · Mathematics 2025-09-19 Bart Rosenzweig , Jonathan Stanfill

For doubling weights, we obtain a necessary and sufficient condition such that the one weighted inequality of the integral operator induced by Hardy kernels on the unit disk holds. This confirms a conjecture by Guo and Wang in such…

Functional Analysis · Mathematics 2025-04-15 Zipeng Wang , Kenan Zhang

We give a simple proof of a recently result concerning Hardy $q$-inequalities.

Classical Analysis and ODEs · Mathematics 2014-12-18 Peng Gao

Morrey's classical inequality implies the H\"older continuity of a function whose gradient is sufficiently integrable. Another consequence is the Hardy-type inequality $$ \lambda\biggl\|\frac{u}{d_\Omega^{1-n/p}}\biggr\|_{\infty}^p\le…

Analysis of PDEs · Mathematics 2025-04-17 Ryan Hynd , Simon Larson , Erik Lindgren

A new weighted Hardy-type inequality for functions from the Sobolev space $W_{p}^{1}$ is proved. It is assumed that functions vanish on small alternating pieces of the boundary. The proved inequality generalizes the classical known weighted…

Classical Analysis and ODEs · Mathematics 2026-04-17 Yu. O. Koroleva

We establish a novel improvement of the classical discrete Hardy inequality, which gives the discrete version of a recent (continuous) inequality of Frank, Laptev, and Weidl. Our arguments build on certain weighted inequalities based on…

Functional Analysis · Mathematics 2024-07-09 Prasun Roychowdhury , Durvudkhan Suragan

We prove a range of critical Hardy inequalities and uncertainty type principles on one of most general subclasses of nilpotent Lie groups, namely the class of homogeneous groups. Moreover, we establish a new type of critical Hardy…

Analysis of PDEs · Mathematics 2016-11-08 Michael Ruzhansky , Durvudkhan Suragan

For absolutely convergent series we state explicitly a one-sided summation estimate that can be viewed as the discrete analogue of the change of variable formula on the half line. This estimate is implicit in Pascal Lef\`evre's recent…

Classical Analysis and ODEs · Mathematics 2023-07-12 Yi C. Huang

\begin{abstract} In the paper we state conditions on potentials $V$ to get the improved Hardy inequality with weight \begin{equation*} \begin{split} c_{N,\mu}\int_{\R^N}\frac{\varphi^2}{|x|^2}\mu(x)dx&+ \int_{\R^N}V\,\varphi^2\mu(x)dx…

Analysis of PDEs · Mathematics 2022-11-28 Anna Canale

We improve the classical discrete Hardy inequality \begin{equation*}\label{1} \sum _{{n=1}}^{\infty }a_{n}^{2}\geq \left({\frac {1}{2}}\right)^{2} \sum _{{n=1}}^{\infty }\left({\frac {a_{1}+a_{2}+\cdots +a_{n}}{n}}\right)^{2},…

Spectral Theory · Mathematics 2016-12-20 Matthias Keller , Yehuda Pinchover , Felix Pogorzelski