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Related papers: Convexity properties related to extremal functions

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We study the smoothness of the Siciak-Zaharjuta extremal function associated to a convex body in $\mathbb{R}^2$. We also prove a formula relating the complex equilibrium measure of a convex body in $\mathbb{R}^n$ to that of its Robin…

Complex Variables · Mathematics 2015-06-22 D. Burns , N. Levenberg , S. Ma`u

A typical quandary in geometric functions theory is to study a functional composed of amalgamations of the coefficients of the pristine function. Conventionally, there is a parameter over which the extremal value of the functional is…

Complex Variables · Mathematics 2018-09-19 P. Gochhayat , A. Prajapati , A. K. Sahoo

In approximation theory, logarithmic derivatives of complex polynomials are called simple partial fractions (SPF) as suggested by Eu.P. Dolzhenko. Many solved and unsolved extremal problems related to SPF are traced back to works of G.…

Classical Analysis and ODEs · Mathematics 2017-10-17 V. I. Danchenko , M. A. Komarov , P. V. Chunaev

We obtain two-bound estimates for the local growth of pluri-subharmonic functions in terms of Siciak and relative extremal functions. As applications, we give simple new proofs of "Bernstein doubling inequality" and the main result in…

Complex Variables · Mathematics 2009-12-03 Tuyen Trung Truong

We establish disc formulas for the Siciak-Zahariuta extremal function of an arbitrary open subset of complex affine space, generalizing Lempert's formula for the convex case. This function is also known as the pluricomplex Green function…

Complex Variables · Mathematics 2007-05-23 Finnur Larusson , Ragnar Sigurdsson

This paper is devoted to study the approximation properties and rate of approximation of the Szasz-Mirakjan-Kantrovich-Stancu type polynomials generated by the Dunkl generalization of the exponential function with respect to q -calculus. We…

Classical Analysis and ODEs · Mathematics 2016-03-21 M. Mursaleen , Md. Nasiruzzaman

The Polyak-{\L}ojasiewicz (P{\L}) inequality extends the favorable optimization properties of strongly convex functions to a broader class of functions. In this paper, we prove a theorem (also obtained by Criscitiello, Rebjock and Boumal in…

Optimization and Control · Mathematics 2026-01-19 Aziz Ben Nejma

In this paper, we prove the second-order Sobolev inequalities on Cayley graphs of groups of polynomial growth. We use the discrete Concentration-Compactness principle to prove the existence of extremal functions for best constants in…

Analysis of PDEs · Mathematics 2022-05-03 Bobo Hua , Ruowei Li , Florentin Münch

The paper presents a review of the state-of-the-art of subgradient and accelerated methods of convex optimization, including in the presence of disturbances and access to various information about the objective function (function value,…

This work extends the Mond-Pecaric method to functions with multiple operators as arguments by providing arbitrarily close approximations of the original functions. Instead of using linear functions to establish lower and upper bounds for…

Functional Analysis · Mathematics 2024-07-09 Shih-Yu Chang

It is known that when minimizing smooth Polyak-{\L}ojasiewicz (PL) functions, momentum algorithms cannot significantly improve the convergence bound of gradient descent, contrasting with the acceleration phenomenon occurring in the strongly…

Optimization and Control · Mathematics 2026-02-11 Julien Hermant

The classical Lojasiewicz inequality and its extensions for partial differential equation problems (Simon) and to o-minimal structures (Kurdyka) have a considerable impact on the analysis of gradient-like methods and related problems:…

Optimization and Control · Mathematics 2008-02-07 Jerome Bolte , Aris Daniilidis , Olivier Ley , Laurent Mazet

We use our disc formula for the Siciak-Zahariuta extremal function to characterize the polynomial hull of a connected compact subset of complex affine space in terms of analytic discs.

Complex Variables · Mathematics 2007-05-23 Finnur Larusson , Ragnar Sigurdsson

We prove new Bernstein and Markov type inequalities in $L^p$ spaces associated with the normal and the tangential derivatives on the boundary of a general compact $C^\alpha$-domain with $1\leq \alpha\leq 2$. These estimates are also applied…

Numerical Analysis · Mathematics 2025-03-21 Feng Dai , András Kroó , Andriy Prymak

Many practical optimization problems lack strong convexity. Fortunately, recent studies have revealed that first-order algorithms also enjoy linear convergences under various weaker regularity conditions. While the relationship among…

Optimization and Control · Mathematics 2026-02-05 Feng-Yi Liao , Lijun Ding , Yang Zheng

We prove two disc formulas for the Siciak-Zahariuta extremal function of an arbitrary open subset of complex affine space. We use these formulas to characterize the polynomial hull of an arbitrary compact subset of complex affine space in…

Complex Variables · Mathematics 2008-08-26 Finnur Larusson , Ragnar Sigurdsson

We investigate random compact sets with random functions defined thereon, such as polynomials, rational functions, the pluricomplex Green function and the Siciak extremal function. One surprising consequence of our study is that randomness…

Complex Variables · Mathematics 2020-11-06 Paul M. Gauthier , Thomas Ransford , Simon St-Amant , Jérémie Turcotte

The Alexandrov-Fenchel inequality, a far-reaching generalization of the classical isoperimetric inequality to arbitrary mixed volumes, lies at the heart of convex geometry. The characterization of its extremal bodies is a long-standing open…

Metric Geometry · Mathematics 2022-02-04 Yair Shenfeld , Ramon van Handel

In this article the solution of the special problem of the conditional extremum for the conjugate trigonometric polynomials is given. A possibility to apply this result to the problems of optimal stabilization of quasidynamic chaos in…

Classical Analysis and ODEs · Mathematics 2012-10-03 D. V. Dmitrishin , A. D. Khamitova

In this expository paper we collect many recent advances in analytic function spaces of several complex variables related with trace problem in tubular domains over symmetric cones and bounded strongly pseudoconvex domains with smooth…

Complex Variables · Mathematics 2025-10-28 R. F. Shamoyan , N. M. Makhina