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 An arithmetic van der Corput trick and the polynomial van der Waerden theorem
 Piecewise syndetic sets, topological dynamics and ultrafilters
 Measure preserving actions of affine semigroups and {x+y,xy} patterns
 Szemerédi Theorem Part VI – Dichotomy between weak mixing and compact extension
 Gaussian systems
Tag Archives: Szemeredi’s theorem
Szemerédi Theorem Part VI – Dichotomy between weak mixing and compact extension
This is the sixth and final post in a series about Szemerédi’s theorem. In this post I complete the proof of the Multiple Recurrence Theorem, which I showed in a previous post of this series to be equivalent to Szemerédi’s … Continue reading
Posted in Ergodic Theory, Ramsey Theory
Tagged Compact extensions, joinings, Szemeredi's theorem, weak mixing
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Szemerédi’s Theorem Part V – Compact extensions
This is the fifth in a series of six posts I am writing about Szemerédi’s theorem. In the previous post I proved that the Sz property lifts through weak mixing extension and in this post I will prove that the … Continue reading
Posted in Ergodic Theory
Tagged almost periodic, Compact extensions, Furstenberg, Szemeredi's theorem
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Szemerédi’s Theorem Part IV – Weak mixing extensions
This is the fourth in a series of six posts I am writing about Szemerédi’s theorem. In the first three posts, besides setting up the notation and definitions necessary, I reduced Szemerédi’s theorem to three facts. Those three facts are … Continue reading
Pomerance Theorem on colinear points in certain paths in a two dimensional lattice
— 1. Introduction — Van der Waerden’s theorem (to which I gave two proofs in previous posts on this blog) states that if one colors the positive integers with finitely many colors, then one can always find a monochromatic arithmetic … Continue reading
Szemerédi’s Theorem Part III – Precise definitions
This is the third in a series of six posts on Szemerédi’s theorem. In the previous post I outlined the ideas of the ergodic theoretical proof by Furstenberg. In this post I will set up the machinery and give the … Continue reading
Posted in Combinatorics, Ergodic Theory, Ramsey Theory
Tagged almost periodic, skew product, Szemeredi's theorem, weak mixing
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Szemerédi’s Theorem Part II – Overview of the proof
This is the second in a series of posts about Szemerédi’s theorem. In the first post I presented the first step in the proof of Szemerédi’ theorem, namely applying the correspondence principle of Furstenberg to transform the problem into one … Continue reading
Posted in Combinatorics, Ergodic Theory
Tagged almost periodic, cesaro limit, Extension, factor, Furstenberg, Syndetic sets, Szemerédi, Szemeredi's theorem, weak mixing
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Szemerédi’s Theorem Part I – Equivalent formulations
The theorem of van der Waerden on arithmetic progressions, whose precise statement and proof can be found in a previous post of mine, states that in a finite partition of the set of positive integers, one of the pieces contains … Continue reading
Posted in Combinatorics, Ergodic Theory, Ramsey Theory
Tagged Furstenberg, Szemeredi's theorem
6 Comments