S. Astashkin

activity

20242026

collaborators

4 papers

math.FA2026

Rigidity of sets of independent functions in symmetric spaces

Sergey V. Astashkin, Yu. V. Malykhin

We say that a symmetric function space $X$ has the $(I R)$ property whenever all sets of $N$ independent mean zero functions $f_{1}, \dots, f_{N} \in X$ , $∥ f_{k} ∥_{X} \geq 1$ , are poorly appr…

math.FA2025

On extreme points of the unit ball of a Hardy-Lorentz space

Sergey V. Astashkin

We investigate the problem of a characterization of extreme points of the unit ball of a Hardy-Lorentz space $H (I^ (I ¨ ))$ , posed by Semenov in 1978. New necessary and sufficient con…

math.FA2025

Looking for a continuous version of Bennett--Carl theorem

Sergey V. Astashkin, Karol LeÅnik, MichaÅ Wojciechowski

We study absolute summability of inclusions of r.i. function spaces. It appears that such properties are closely related, or even determined by absolute summability of inclusions o…

math.PR2024

Random unconditional convergence of Rademacher chaos in $L_{\infty}$ and sharp estimates for discrepancy of weighted graphs and hypergraphs

Sergey V. Astashkin, Konstantin V. Lykov

We prove that both multiple Rademacher system and Rademacher chaos possess the property of random unconditional convergence in the space $L_{\infty}$ . This fact combined with some in…

Rigidity of sets of independent functions in symmetric spaces

On extreme points of the unit ball of a Hardy-Lorentz space

Looking for a continuous version of Bennett--Carl theorem

Random unconditional convergence of Rademacher chaos in L∞​ and sharp estimates for discrepancy of weighted graphs and hypergraphs

Random unconditional convergence of Rademacher chaos in $L_{\infty}$ and sharp estimates for discrepancy of weighted graphs and hypergraphs