SWW Sequences and the Infinite Ergodic Random Walk

  • S. EigenEmail author
  • A. Hajian
  • V. Prasad
Real and Complex Analysis


This article is concerned with demonstrating the power and simplicity of sww (special weakly wandering) sequences. We calculate an sww growth sequence for the infinite measure preserving random walk transformation. From this we obtain the first explicit eww (exhaustive weakly wandering) sequence for the transformation. The exhaustive property of the eww sequence is a “gift” from the sww sequence and requires no additional work. Indeed we know of no other method for finding explicit eww sequences for the random walk map or any other infinite ergodic transformation. The result follows from a detailed analysis of the proof of Theorem 3.3.12 in the book S.Eigen, A.Hajian, Y.Ito, V.Prasad, Weakly Wandering Sequences in Ergodic Theory (Springer, Tokyo, 2014) as applied to the random walk transformation from which an sww growth sequence is obtained.We explain the significance of sww sequences in the construction of eww sequences.


Special weakly wandering growth sequence exhaustive weakly wandering infinite measure preserving transformation random walk 

MSC2010 numbers

37A40 60G50 82C41 


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Copyright information

© Allerton Press, Inc. 2019

Authors and Affiliations

  1. 1.Northeastern UniversityBostonUSA
  2. 2.University of MassachusettsLowellUSA

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