{ "id": "2407.13741", "version": "v1", "published": "2024-07-18T17:48:45.000Z", "updated": "2024-07-18T17:48:45.000Z", "title": "Non-commuting transformations with non-converging 2-fold ergodic averages", "authors": [ "Valery V. Ryzhikov" ], "comment": "in English and Russian versions", "categories": [ "math.DS" ], "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 $S,T$, some set $A$ of positive finite measure and a sequence $N_m$ with $|N_{m+1}|/|N_m|\\ \\to\\infty$ such that $T^iA\\cap S^iA=\\phi$ for $i\\in [N_{4k}, N_{4k+1}]$ and $T^iA=S^iA$ for $i\\in [N_{4k+2}, N_{2k+3}]$. For the corresponding deterministic Gaussian and Poisson suspensions $S_\\circ,T_\\circ$ over $S,T$ for some $f\\in L_\\infty$ there is not a limit of $ \\frac 1 N \\sum_{n=1}^N T_\\circ^nf\\,S_\\circ^nf$ in $ L_2$.", "revisions": [ { "version": "v1", "updated": "2024-07-18T17:48:45.000Z" } ], "analyses": { "keywords": [ "ergodic averages", "non-commuting transformations", "song shao", "tim austin", "wen huang" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }