English

Non-commuting transformations with non-converging 2-fold ergodic averages

Dynamical Systems 2024-08-05 v3

Abstract

In connection with the results of Tim Austin, and Wen Huang, Song Shao, Xiangdong Ye we present the following assertion: there are infinite automorphisms S,TS,T, some set AA of positive finite measure and a sequence NmN_m with Nm+1/Nm |N_{m+1}|/|N_m|\ \to\infty such that TiASiA=ϕT^iA\cap S^iA=\phi for i[N4k,N4k+1]i\in [N_{4k}, N_{4k+1}] and TiA=SiAT^iA=S^iA for i[N4k+2,N2k+3]i\in [N_{4k+2}, N_{2k+3}]. For the corresponding deterministic Gaussian and Poisson suspensions S,TS_\circ,T_\circ over S,TS,T for some fLf\in L_\infty there is no limit of 1Nn=1NTnfSnf \frac 1 N \sum_{n=1}^N T_\circ^nf\,S_\circ^nf in L2 L_2.

Keywords

Cite

@article{arxiv.2407.13741,
  title  = {Non-commuting transformations with non-converging 2-fold ergodic averages},
  author = {Valery V. Ryzhikov},
  journal= {arXiv preprint arXiv:2407.13741},
  year   = {2024}
}

Comments

in Russian

R2 v1 2026-06-28T17:46:23.605Z