Abstract
We prove the optimality of a criterion of Koksma (1953) in Khinchin’s conjecture on strong uniform distribution. This verifies a claim of Bourgain (1988) and leads also to a near optimal a.e. convergence condition for series Σ ∞ k=1 c k f(kx) with f ∈ L 2. Finally, we show that under mild regularity conditions on the Fourier coefficients of f, the Khinchin conjecture is valid assuming only f ∈ L 2.
Similar content being viewed by others
References
C. Aistleitner, Convergence of Σc k f(kx) and the Lip α class, Proceedings of the American Mathematical Society 140 (2012), 3893–3903.
C. Aistleitner, I. Berkes and C. Seip, GCD sums from Poisson integrals and systems of dilated functions, arXiv:1210.0741v3 [math.NT]
G. Alexits, Convergence problems of orthogonal series, Pergamon Press, Oxford, 1961.
I. Berkes, On the convergence of Σc n f(nx) and the Lip 1/2 class, Transactions of the American Mathematical Society 349 (1997), 4143–4158.
I. Berkes and M. Weber, On the convergence of Σc k f(n k x), Memoirs of the American Mathematical Society 201 (2009), 1–72.
I. Berkes and M. Weber, On series of dilated functions, Quarterly Journal of Mathematics, to appear.
N. Bingham, C. Goldie and J. Teugels, Regular Variation, Cambridge University Press, 1987.
J. Bourgain, Almost sure convergence and bounded entropy, Israel Journal of Mathematics 63 (1988), 79–95.
J. Brémont, Davenport series and almost sure convergence, Quarterly Journal of Mathematics 62 (2011), 825–843.
L. Carleson, On convergence and growth of partial sums of Fourier series, Acta Mathematica 116 (1966), 135–157.
V. F. Gaposhkin, On series by the system ϕ(nx), (in Russian) Math. Sbornik 69 (1966), 328–353.
V. F. Gaposhkin, Lacunary series and independent functions, Russian Mathematical Surveys 21(6) (1966), 1–82.
V. F. Gaposhkin, On convergence and divergence systems, Matematicheskie Zametki 4 (1968), 253–260.
T. H. Gronwall, Some asymptotic expressions in the theory of numbers, Transactions of the American Mathematical Society 14 (1913), 113–122.
G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, Fourth edn. Clarendon Press, Oxford, 1960.
G. Harman, Metric number theory, Clarendon Press, Oxford, 1998.
A. J. Khinchin, Ein Satz über Kettenbrüche mit arithmetischen Anwendungen, Mathematische Zeitschrift 18 (1923), 289–306.
J. F. Koksma, A diophantine property of summable functions, Indian Journal of Mathematics Society 15 (1951), 87–96.
J. F. Koksma, Estimations de fonctionsà l’aide d’intégrales de Lebesgue, Bulletin of the Belgian Mathematical Society 6 (1953), 4–13.
J. M. Marstrand, On Khinchin’s conjecture about strong uniform distribution, Proceedings London Mathematical Society 21 (1970), 540–556.
E. M. Nikishin, Resonance theorems and superlinear operators, Russian Mathematicsl Surveys 25(6) (1970), 125–187.
M. Weber, Dynamical Systems and Processes, IRMA Lectures in Theoretical and Mathematical Physics Vol. 14, European Mathematical Society Publishing House, Zürich, 2009.
M. Weber, On systems of dilated functions, Comptes Rendus de l’Académie des Sciences Paris 349 (2011), 1261–1263.
A. Wintner, The Theory of Measure in Arithmetical Semi-Groups, Waverly Press, Baltimore, Md., 1944.
Author information
Authors and Affiliations
Corresponding author
Additional information
Research supported by FWF Grant P 24302-N18 and OTKA Grant K 81928.
Rights and permissions
About this article
Cite this article
Berkes, I., Weber, M. On series Σc k f(kx) and Khinchin’s conjecture. Isr. J. Math. 201, 593–609 (2014). https://doi.org/10.1007/s11856-014-0036-0
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11856-014-0036-0