Hostname: page-component-8448b6f56d-c47g7 Total loading time: 0 Render date: 2024-04-17T07:03:14.658Z Has data issue: false hasContentIssue false

The strong sweeping out property for lacunary sequences, Riemann sums, convolution powers, and related matters

Published online by Cambridge University Press:  19 September 2008

Mustafa Akcoglu
Affiliation:
Department of Mathematics, University of Toronto, Toronto, Ontario M5S 1A1, Canada
Alexandra Bellow
Affiliation:
Department of Mathematics, Northwestern University, Evanston, IL 60201, USA
Roger L. Jones
Affiliation:
Department of Mathematics, DePaul University, 2219 N. Kenmore, Chicago, IL 60614, USA
Viktor Losert
Affiliation:
Institute of Mathematics, University of Vienna, A-1090 Vienna, Austria
Karin Reinhold-Larsson
Affiliation:
Department of Mathematics, SUNY at Albany, Albany NY 12222, USA
Máté Wierdl
Affiliation:
Department of Mathematics, Northwestern University, Evanston, IL 60201, USA

Abstract

In this paper we establish conditions on a sequence of operators which imply divergence. In fact, we give conditions which imply that we can find a set B of measure as close to zero as we like, but such that the operators applied to the characteristic function of this set have a lim sup equal to 1 and a lim inf equal to 0 a.e. (strong sweeping out). The results include the fact that ergodic averages along lacunary sequences, certain convolution powers, and the Riemann sums considered by Rudin are all strong sweeping out. One of the criteria for strong sweeping out involves a condition on the Fourier transform of the sequence of measures, which is often easily checked. The second criterion for strong sweeping out involves showing that a sequence of numbers satisfies a property similar to the conclusion of Kronecker's lemma on sequences linearly independent over the rationals.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1996

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[ABdJJ]Akcoglu, M., Bellow, A., Junco, A. del and Jones, R.. Divergence of averages obtained by sampling a flow. Proc. A.M.S. 118 (1993), 499505CrossRefGoogle Scholar
[AdJ]Akcoglu, M. and Junco, A. del. Convergence of averages of point trsnsformations. Proc. A.M.S. 49 (1975), 265266Google Scholar
[AdJL]Akcoglu, M., del Junco, A. and Lee, W.. A solution to a problem of A. Bellow, Almost Everywhere Convergence II ed. Bellow, A. and Jones, R.. Academic Press, 1991, pp. 17Google Scholar
[B1]Bellow, A.. On bad universal sequences in ergodic theory (II), Springer Verlag Lecture Notes in Math, 1033, 1983.Google Scholar
[B2]Bellow, A.. Sur la structure des suites Mauvaises Universelles en theorie Ergodique. Comptes Rendus Acad. Sci., Paris 294 (1982), 5558Google Scholar
[B3]Bellow, A.. Two problems. Proc. Oberwolfach Conf. Measure Theory (June 1981), Springer Lecture Notes in Math. 945, (1982).Google Scholar
[BJR1]Bellow, A., Jones, R. and Rosenblatt, J.. Almost everywhere convergence of convolution powers. Ergod. Th. & Dynam. Sys. 14 (1994), 415432CrossRefGoogle Scholar
[BJR2]Bellow, A., Jones, R. and Rosenblatt, J.. Convergence for moving averages. Ergod. Th. & Dynam. Sys. 10 (1990), 4362CrossRefGoogle Scholar
[BBB]Bergelson, V., Bourgain, J. and Boshernitzan, M.. Some results on non-linear recurrence. J. d'Anal. Math. 62 (1994), 2946CrossRefGoogle Scholar
[Bo1]Bourgain, J.. Almost sure convergence and bounded entropy. Israel J. Math. 63 (1988), 7997CrossRefGoogle Scholar
[Bo2]Bourgain, J., Problems of almost everywhere convergence related to harmonic analysis and number theory. Israel J. of Math., 71 (1990), 97127Google Scholar
[Bo3]Bourgain, J.. On the maximal ergodic theorem for certain subsets of the integers. Israel J. Math. 61 (1988), 3972Google Scholar
[C]Conze, J. F.. Convergence des moyennes ergodiques pour des sous-suites. Bull. Sci. Math. France 35 (1973), 715Google Scholar
[dJR]Junco, A. del and Rosenblatt, J.. Counter examples in ergodic theory and number theory. Math. Ann. 245 (1979), 185197Google Scholar
[E]Erdös, P. and Taylor, S. J.. On the set of points of convergence of a lacunary trigonometric series, and the equidistribution properties of related sequences. Proc. London Math. Soc. 7(3) (1957), 598615CrossRefGoogle Scholar
[F]Furstenberg, H.. Recurrence in Ergodic Theory and Combinatorial Number Theory. Princeton University Press, Princeton, 1981.Google Scholar
[JW]Jones, R. and Wierdl, M.. Convergence and divergence of ergodic averages. Ergod. Th. & Dynam. Sys. 14 (1994), 515535Google Scholar
[K1]Krengel, U.. Ergodic Theorems, de Gruyter, Berlin-New York, 1985.CrossRefGoogle Scholar
[K2]Krengel, U.. On the individual ergodic theorem for subsequences. Ann. Math. Stat. 42 (1971), 10911095CrossRefGoogle Scholar
[L]Lind, D.. Locally compact measure preserving flows. Adv. in Math. 15 (1975), 175193CrossRefGoogle Scholar
[P]Pollington, A. D.. On the density of the sequence {nkξ}. Illinois J. of Math. 23 (1979), 511515CrossRefGoogle Scholar
[Pe]Peres, Y.. Personal communication.Google Scholar
[R1]Rosenblatt, J.. Ergodic group actions. Arch. Math. 47 (1986), 263269Google Scholar
[R2]Rosenblatt, J.. Universally bad sequences in ergodic theory. Almost Everywhere Convergence II. ed. Bellow, A. and Jones, R.. Academic Press, 1991, pp. 227245.CrossRefGoogle Scholar
[R]Rota, G. C.. An ‘Alternierende Verfahren’ for general positive operators. Bull. A.M.S. 68 (1962), 95102CrossRefGoogle Scholar
[Ru]Rudin, W.. An arithmetic property of Riemann sums. P. A. M. S. 15 (1964), 321324Google Scholar
[S]Smorodinsky, M.. Ergodic Theory, Entropy. Springer-Verlag, New York, 1971.Google Scholar
[St]Starr, N.. Operator limit theorems. Trans. A.M.S. 121 (1966), 90115CrossRefGoogle Scholar
[U]Ullrich, D.. Personal communication.Google Scholar
[W]Wierdl, M.. Almost everywhere convergence and recurrence along subsequences in ergodic theory. Ph.D Thesis, Ohio State University, 1989.Google Scholar