English
Related papers

Related papers: The Sz\'asz inequality for matrix polynomials and …

200 papers

The main aim of this work is to apply the matrix approach of ortho\-gonal polynomials associated with infinite Hermitian definite positive matrices in relation with an important question regarding the location of zeros of Sobolev orthogonal…

Functional Analysis · Mathematics 2025-03-20 Carmen Escribano , Raquel Gonzalo

We prove logarithmic Sobolev inequalities and concentration results for convex functions and a class of product random vectors. The results are used to derive tail and moment inequalities for chaos variables (in spirit of Talagrand and…

Probability · Mathematics 2007-05-23 Radoslaw Adamczak

We generalize the Bernstein-Walsh-Siciak theorem on polynomial approximation in $\mathbb{C}^n$ to the case where the polynomial ring $\mathcal{P}(\mathbb{C}^n)$ is replaced by a subring $\mathcal{P}^S(\mathbb{C}^n)$ consisting of all…

Complex Variables · Mathematics 2024-10-30 Benedikt Steinar Magnússon , Ragnar Sigurðsson , Bergur Snorrason

The paper is concerned with sharp estimates of constants in Poincare type inequalities for functions having zero mean value on the boundary of a Lipschitz domain or on a measurable part of it. These estimates are useful for various…

Numerical Analysis · Mathematics 2016-02-05 Svetlana Matculevich , Sergey Repin

Employing the Orlicz functions we extend the Buzano's inequality which is a refinement of the Cauchy-Schwarz inequality. Also using the Orlicz functions we obtain several numerical radius inequalities for a bounded linear operator as well…

Functional Analysis · Mathematics 2024-08-26 Pintu Bhunia , Raj Kumar Nayak

Recently Rather et al. \cite{NT} considered the generalized derivative and the generalized polar derivative and studied the relative position of zeros of generalized derivative and generalized polar derivative with respect to the zeros of…

Classical Analysis and ODEs · Mathematics 2026-01-21 N. A. Rathe , D. R. Bhat , I. Dar

In this work, an extension of the generalized mixed Schwarz inequality is proved. A companion of the generalized mixed Schwarz inequality is established by merging both Cartesian and Polar decompositions of operators. Based on that some…

Functional Analysis · Mathematics 2018-11-06 Mohammad W. Alomari

Let $\Re_n$ be the set of all rational functions of the type $r(z) = p(z)/w(z),$ where $p(z)$ is a polynomial of degree at most $n$ and $w(z) = \prod_{j=1}^{n}(z-a_j)$, $|a_j|>1$ for $1\leq j\leq n$. In this paper, we set up some results…

Complex Variables · Mathematics 2026-02-03 N. A. Rather , Tanveer Bhat , Danish Rashid Bhat

We derive the Hasse principle and weak approximation for pencils of certain varieties in the spirit of work by Colliot-Th\'el\`ene,Sansuc and Harpaz-Skorobogatov-Wittenberg. Our varieties are defined through polynomials in many variables…

Number Theory · Mathematics 2019-08-15 Kevin Destagnol , Efthymios Sofos

Let $ P(z) $ be a polynomial of degree $ n $ and for any real or complex number $\alpha,$ let $D_\alpha P(z)=nP(z)+(\alpha-z)P^{\prime}(z)$ denote the polar derivative with respect to $\alpha.$ In this paper, we obtain generalizations of…

Complex Variables · Mathematics 2013-04-03 N. A. Rather , Suhail Gulzar

We obtain several Cauchy-like and Pellet-like results for the zeros of a general complex polynomial by considering similarity transformations of the squared companion matrix and the reformulation of the zeros of a scalar polynomial as the…

Numerical Analysis · Mathematics 2016-01-05 Aaron Melman

In this article,we first give a modified Schwarz-Pompeiu formula in a general sector ring by proper conformal mappings, and obtain the solution of the Schwarz problem for the Cauchy-Riemann equation in explicit forms. Furthermore, a class…

Complex Variables · Mathematics 2022-02-01 Zhihua Du , Ying Wang , Min Ku

We establish a new description of the Schur-Agler norm of a holomorphic function on the polydisc as the solution of a convex optimization problem. Consequences of this description are explored both from a theoretical and from a practical…

Functional Analysis · Mathematics 2026-02-17 Michael Hartz , Yi Wang

Inequalities for Riesz potentials are well-known to be equivalent to Sobolev inequalities of the same order for domain norms ``far" from $L^1$, but to be weaker otherwise. Recent contributions by Van Schaftingen, by Hernandez, Rai\c{t}\u{a}…

Functional Analysis · Mathematics 2025-12-09 D. Breit , A. Cianchi , D. Spector

We give a short and elementary proof of an inverse Bernstein-type inequality found by S. Khrushchev for the derivative of a polynomial having all its zeros on the unit circle. The inequality is used to show that equally-spaced points solve…

Metric Geometry · Mathematics 2015-09-23 Tamás Erdélyi , Douglas P. Hardin , Edward B. Saff

In this paper, we establish a class of Stein-Weiss type inequality with partial variable weight functions on the upper half space using a weighted Hardy type inequality. Overcoming the impact of weighted functions, the existence of extremal…

Analysis of PDEs · Mathematics 2024-12-31 Jingbo Dou , Jingjing Ma

In the present work, we propose to investigate the Fekete-Szeg\"o inequalities certain classes of analytic and bi-univalent functions defined by subordination. The results in the bounds of the third coefficient which improve many known…

Complex Variables · Mathematics 2014-04-04 Halit Orhan , N. Magesh , V. K. Balaji

In this paper, we present a correct proof of an $L_p$-inequality concerning the polar derivative of a polynomial with restricted zeros. We also extend Zygmund's inequality to the polar derivative of a polynomial.

Complex Variables · Mathematics 2007-09-24 A. Aziz , N. A. Rather

The main aim of this work is to give a general approach to the celebrated Kahane-Salem-Zygmund inequalities. We prove estimates for exponential Orlicz norms of averages $\sup_{1\le j \leq N} \big |\sum_{1 \leq i \leq K}\gamma_i(\cdot)…

Functional Analysis · Mathematics 2020-08-12 Andreas Defant , Mieczysław Mastyło

We prove some P\'olya-Szeg\"o type inequalities which involve couples of functions and their rearrangements. Our inequalities reduce to the classical P\'olya-Szeg\"o principle when the two functions coincide. As an application, we give a…

Analysis of PDEs · Mathematics 2017-04-07 Friedemann Brock , Adele Ferone , Francesco Chiacchio , Anna Mercaldo