Averages along cubes for not necessarily commuting measure preserving transformations

Idris Assani

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Averages along cubes for not necessarily commuting measure preserving transformations

Idris Assani

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Abstract

We study the pointwise convergence of some weighted averages linked to averages along cubes. We show that if $(X,\mathcal{B},\mu, T_i)$ are not necessarily commuting measure preserving systems on the same finite measure space and if $f_i,$ $1\leq i\leq 6$ are bounded functions then the averages $$\frac{1}{N^3}\sum_{n, m, p=1}^N f_1(T_1^nx) f_2(T_2^mx) f_3(T_3^px) f_4(T_4^{n+m}x) f_5(T_5^{n+p}x) f_6(T_6^{m+p}x)$$ converge almost everywhere.

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BibTeX RIS

Idris Assani. 2005-11-02. Averages along cubes for not necessarily commuting measure preserving transformations. https://arxiv.org/abs/math/0511062

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