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Related papers: Sharp Hardy's Inequalities in Hilbert Spaces

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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

The main aim of this note is to prove sharp weighted integral Hardy inequality and conjugate integral Hardy inequality on homogeneous Lie groups with any quasi-norm for the range $1<p\leq q<\infty.$ We also calculate the precise value of…

Analysis of PDEs · Mathematics 2022-02-15 Michael Ruzhansky , Anjali Shriwastawa , Bankteshwar Tiwari

In this paper we obtain some sharp Hardy inequalities with weight functions that may admit singularities on the unit sphere. In order to prove the main results of the paper we use some recent sharp inequalities for the lowest eigenvalue of…

Analysis of PDEs · Mathematics 2014-08-26 Thomas Hoffmann-Ostenhof , Ari Laptev

We study finite sections of weighted Hardy's inequality following the approach of De Bruijn. Similar to the unweighted case, we obtain an asymptotic expression for the optimal constant.

Classical Analysis and ODEs · Mathematics 2007-12-12 Peng Gao

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 a recent study of Bessel operators in connection with a refinement of Hardy's inequality involving $1/\sin^2(x)$ on the finite interval $(0,\pi)$, we now take a closer look at the underlying Bessel-type operators with more…

Classical Analysis and ODEs · Mathematics 2024-07-30 Fritz Gesztesy , Michael M. H. Pang , Jonathan Stanfill

For $p,q\geq2$, the Hardy and Littlewood inequalities for real bilinear forms, in its unified formulation, assert that there is a constant $C_{p,q}\geq1$ such that \begin{equation}…

Number Theory · Mathematics 2018-04-03 Daniel Nunez-Alarcon , Daniel Pellegrino

We determine the sharp constant in the Hardy inequality for fractional Sobolev spaces on half-spaces. Our proof relies on a non-linear and non-local version of the ground state representation.

Functional Analysis · Mathematics 2009-06-09 Rupert L. Frank , Robert Seiringer

We prove the existence of an extremal function in the Hardy-Littlewood-Sobolev inequality for the energy associated to an stable operator. To this aim we obtain a concentration-compactness principle for stable processes in $\mathbb{R}^N$.

Analysis of PDEs · Mathematics 2021-05-17 Arturo de Pablo , Fernando Quirós , Antonella Ritorto

In this paper, we consider a weighted version of one-dimensional discrete Hardy inequalities with power weights of the form $n^\alpha$. We prove the inequality when $\alpha$ is an even natural number with the sharp constant and remainder…

Functional Analysis · Mathematics 2024-03-12 Shubham Gupta

We study the sharp constant in the Morrey inequality for fractional Sobolev-Slobodecki\u{\i} spaces on the whole $\mathbb{R}^N$. By generalizing a recent work by Hynd and Seuffert, we prove existence of extremals, together with some…

Analysis of PDEs · Mathematics 2023-09-13 Lorenzo Brasco , Francesca Prinari , Firoj Sk

We review the literature concerning the Hardy inequality for regions in Euclidean space and in manifolds, concentrating on the best constants. We also give applications of these inequalities to boundary decay and spectral approximation.

Spectral Theory · Mathematics 2007-05-23 E B Davies

In this paper, we study the existence of extremal functions of the discrete Sobolev inequality and Hardy-Littlewood-Sobolev inequality on lattice graphs. We introduce the discrete Concentration-Compactness principle, and prove the existence…

Analysis of PDEs · Mathematics 2021-07-01 Bobo Hua , Ruowei Li

The first goal of this paper is to study necessary and sufficient conditions to obtain the attainability of the \textit{fractional Hardy inequality } $$\Lambda_{N}\equiv\Lambda_{N}(\Omega):=\inf_{\{\phi\in \mathbb{E}^s(\Omega, D), \phi\neq…

Analysis of PDEs · Mathematics 2017-09-26 Boumediene Abdellaoui , Ahmed Attar , Abdelrazek Dieb , Ireneo Peral

We prove a sharp integral inequality valid for non-negative functions defined on $[0,1]$, with given $L^1$ norm. This is in fact a generalization of the well known integral Hardy inequality. We prove it as a consequence of the respective…

Functional Analysis · Mathematics 2014-12-09 Eleftherios N. Nikolidakis

We study the Hardy type inequalities in the framework of equalities. We present equalities which immediately imply Hardy type inequalities by dropping the remainder term. Simultaneously we give a characterization of the class of functions…

Analysis of PDEs · Mathematics 2016-11-14 Shuji Machihara , Tohru Ozawa , Hidemitsu Wadade

We give the full solution of the following problem: obtain sharp inequalities between the moduli of smoothness $\omega_\alpha(f,t)_q$ and $\omega_\beta(f,t)_p$ for $0<p<q\le \infty$. A similar problem for the generalized $K$-functionals and…

Classical Analysis and ODEs · Mathematics 2017-11-23 Yurii Kolomoitsev , Sergey Tikhonov

In this paper we state the weighted Hardy inequality \begin{equation*} c\int_{{\mathbb R}^N}\sum_{i=1}^n \frac{\varphi^2 }{|x-a_i|^2}\, \mu(x)dx\le \int_{{\mathbb R}^N} |\nabla\varphi|^2 \, \mu(x)dx +k \int_{\mathbb{R}^N}\varphi^2 \,…

Analysis of PDEs · Mathematics 2023-02-08 Anna Canale

In this paper, we study the best constant of the following discrete Hardy-Littlewood-Sobolev inequality, \begin{equation} \sum_{i,j,i\neq j}\frac{f_{i}g_{j}}{\mid i-j\mid^{n-\alpha}}\leq C_{r,s,\alpha} |f|_{l^r} |g|_{l^s},…

Functional Analysis · Mathematics 2013-09-18 Genggeng Huang , Congming Li , Ximing Yin

The Hardy--Littlewood inequalities for multilinear forms on sequence spaces state that for all positive integers $m,n\geq2$ and all $m$-linear forms $T:\ell_{p_{1}}^{n}\times\cdots\times\ell_{p_{m}}^{n}\rightarrow\mathbb{K}$…

Functional Analysis · Mathematics 2018-03-06 Gustavo Araújo , Kleber Câmara