Abstract
We prove theL 2 convergence for an ergodic average of a product of functions evaluated along polynomial times in a totally ergodic system. For each set of polynomials, we show that there is a particular factor, which is an inverse limit of nilsystems, that controls the limit behavior of the average. For a general system, we prove the convergence for certain families of polynomials.
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Dedicated to Hillel Furstenberg upon his retirement
The second author was partially supported by NSF grant DMS-0244994.
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Host, B., Kra, B. Convergence of polynomial ergodic averages. Isr. J. Math. 149, 1–19 (2005). https://doi.org/10.1007/BF02772534
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DOI: https://doi.org/10.1007/BF02772534