Coboundaries of nonconventional ergodic averages

Idris Assani

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arXiv · 1805.07655

Coboundaries of nonconventional ergodic averages

Idris Assani

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Abstract

Let $(X,\mathcal{A}, \mu)$ be a probability measure space and let $T_i,$ $1\leq i\leq H,$ be invertible bi measurable measure preserving transformations on this measure space. We give a sufficient condition for the product of $H$ bounded functions $f_1, f_2, ..., f_H$ to be a coboundary. This condition turns out to be also necessary when one seeks bounded coboundaries.

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Idris Assani. 2018-05-19. Coboundaries of nonconventional ergodic averages. https://arxiv.org/abs/1805.07655

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