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Related papers: Sharp Sobolev inequalities on the complex sphere

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We give sharp limiting case Hardy inequalities on the sphere $\mathbb{S}^{2}$ and show that their optimal constants are unattainable by any $f\in H^{1}\left(\mathbb{S}^{2}\right)\setminus\{0\}$. The singularity of the problem is related to…

Analysis of PDEs · Mathematics 2017-11-03 Ahmed A. Abdelhakim

We show that the $\Lp$ Busemann-Petty centroid inequality provides an elementary and powerful tool to the study of some sharp affine functional inequalities with a geometric content, like log-Sobolev, Sobolev and Gagliardo-Nirenberg…

Functional Analysis · Mathematics 2025-03-14 Julian Haddad , C. Hugo Jimenez , Marcos Montenegro

This article develops a novel approach to the representation of singular integral operators of Calder\'on-Zygmund type in terms of continuous model operators, in both the classical and the bi-parametric setting. The representation is…

Classical Analysis and ODEs · Mathematics 2021-01-06 Francesco Di Plinio , Brett D. Wick , Tyler Williams

We consider the Sobolev (Bessel potential) spaces H^ell(R^d, C), and their standard norms || ||_ell (with ell integer or noninteger). We are interested in the unknown sharp constant K_{ell m n d} in the inequality || f g ||_{ell} \leqs…

Functional Analysis · Mathematics 2010-04-02 Carlo Morosi , Livio Pizzocchero

In the present article, solvability in Sobolev spaces is investigated for a class of degenerate stochastic integro-differential equations of parabolic type. Existence and uniqueness is obtained, and estimates are given for the solution.

Probability · Mathematics 2014-06-24 Konstantinos Dareiotis

We prove that the information complexity (i.e., the inverse) of the classical spherical cap $L_2$ discrepancy on the $d$-dimensional sphere $\mathbb{S}^d$ decreases with dimension $d$, indicating a ``blessing of dimensionality'' for the…

Numerical Analysis · Mathematics 2026-04-24 Johann S. Brauchart , Josef Dick , Friedrich Pillichshammer

This article establishes an interior gradient higher integrability result for weak solutions to parabolic multi-phase problems. The prototype equation for the parabolic multi-phase problem of $p$-Laplace type is given by \[ u_t -…

Analysis of PDEs · Mathematics 2024-11-12 Abhrojyoti Sen

We obtain sharp fractional Hardy inequalities for the half-space and for convex domains. We extend the results of Bogdan and Dyda and of Loss and Sloane to the setting of Sobolev-Bregman forms.

Analysis of PDEs · Mathematics 2026-01-05 Michał Kijaczko , Julia Lenczewska

We determine the sharp constants for the fractional Sobolev inequalities associated with the conformally invariant fractional powers $\mathcal{L}_{s}(0<s<1)$ of the sublaplacian on H-type groups. From these inequalities we derive a sharp…

Analysis of PDEs · Mathematics 2024-06-28 Yaojun Wang , Qiaohua Yang

We prove sharp inequalities for determinants of Toeplitz operators and twisted Laplace operators on the two-sphere, generalizing the Moser-Trudinger-Onofri inequality. In particular a sharp version of conjectures of Gillet-Soule and Fang…

Complex Variables · Mathematics 2009-05-27 Robert J. Berman

This paper is a second one following our work [CLZ13] in series, considering sharp Hardy- Littlewood-Sobolev inequalities on groups of Heisenberg type. The first important breakthrough was made by Frank and Lieb in [FL12]. In this paper,…

Functional Analysis · Mathematics 2014-07-15 Michael Christ , Heping Liu , An Zhang

In dimensions $d \in \{3,4,5,6,7\}$, we prove that the constant functions on the unit sphere $\mathbb{S}^{d-1}\subset \mathbb{R}^d$ maximize the weighted adjoint Fourier restriction inequality $$ \left| \int_{\mathbb{R}^d}…

Classical Analysis and ODEs · Mathematics 2024-10-15 Emanuel Carneiro , Giuseppe Negro , Diogo Oliveira e Silva

In this article, we consider mixed local and nonlocal Sobolev $(q,p)$-inequalities with extremal in the case $0<q<1<p<\infty$. We prove that the extremal of such inequalities is unique up to a multiplicative constant that is associated with…

Analysis of PDEs · Mathematics 2021-06-09 Prashanta Garain , Alexander Ukhlov

We study a class of degenerate parabolic and elliptic equations in divergence form in the upper half space $\{x_d>0\}$. The leading coefficients are of the form $x_d^2a_{ij}$, where $a_{ij}$ are bounded, uniformly elliptic, and measurable…

Analysis of PDEs · Mathematics 2025-06-05 Hongjie Dong , Junhee Ryu

Using some harmonic extensions on the upper-half plane, and probabilistic representations, and curvature-dimension inequalities with some negative dimensions, we obtain some new opimal functional inequalities of the Beckner type for the…

Probability · Mathematics 2018-12-18 Dominique Bakry , Ivan Gentil , Grégory Scheffer

We consider inhomogeneous singular parabolic double phase equations of type $$ u_t-\operatorname{div}(|Du|^{p-2}Du + a(x,t)|Du|^{q-2}Du)=-\operatorname{div} (|F|^{p-2}F + a(x,t)|F|^{q-2}F) $$ in $\Omega_T := \Omega \times (0,T)\subset…

Analysis of PDEs · Mathematics 2026-04-07 Bogi Kim , Jehan Oh

In this paper, we first investigate weighted Minkowski type inequalities for nearly spherical sets in space forms, focusing on the sets that are $C^1$-close to geodesic spheres. Our results generalize the work of \cite{G22} by incorporating…

Differential Geometry · Mathematics 2026-04-29 Weimin Sheng , Yinhang Wang

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 well known duality between the Sobolev inequality and the Hardy-Littlewood-Sobolev inequality suggests that the Nash inequality could also have an interesting dual form, even though the Nash inequality relates three norms instead of…

Functional Analysis · Mathematics 2018-11-28 Eric A. Carlen , Elliott H. Lieb

We prove several new families of Bernstein inequalities of two types on the simplex. The first type consists of inequalities in $L^2$ norm for the Jacobi weight, some of which are sharp, and they are established via the spectral operator…

Classical Analysis and ODEs · Mathematics 2023-07-06 Yan Ge , Yuan Xu