Abstract
It is well known that Luzin’s conjecture has a positive solution for one-dimensional trigonometric Fourier series, but in the multidimensional case it has not yet found its confirmation for spherical partial sums of multiple Fourier series. Historically, progress in solving Luzin’s conjecture has been achieved by considering simpler problems. In this paper, we consider three of these problems for spherical partial sums: the principle of generalized localization, summability almost everywhere, and convergence almost everywhere of multiple Fourier series of smooth functions. A brief overview of the work in these areas is given and unsolved problems are mentioned and new problems are formulated. Moreover, at the end of the work, a new result on the convergence of spherical sums for functions from Sobolev classes is proved.
Similar content being viewed by others
References
Sh. A. Alimov, R. R. Ashurov, and A. K. Pulatov, “Multiple Fourier series and integrals,” Itogi Nauki i Tekhn. Sovrem. Probl. Mat., 42, 7–104 (1989).
Sh. A. Alimov, V. A. Il’in, and E. M. Nikishin, “Convergence problems for multiple trigonometric series and spectral expansions. I,” Usp. Mat. Nauk, 31, 29–86 (1976).
R. R. Ashurov, “On localization conditions for spectral expansions of elliptic operators with constant coefficients,” Mat. Zametki, 33, 434–439 (1983).
R. R. Ashurov, “Summability almost everywhere of Fourier series of functions from Lp in eigenfunctions,” Mat. Zametki, 34, 837–843 (1983).
R. R. Ashurov, “Localization conditions for trigonometric Fourier series,” Dokl. AN SSSR, 31, 496–499 (1985).
R. R. Ashurov, “Summability of multiple trigonometric Fourier series,” Mat. Zametki, 49, 563–568 (1991).
R. R. Ashurov, “Spectral decompositions of elliptic pseudodifferential operators,” Uzb. Mat. Zh., 6, 20–29 (1998).
R. R. Ashurov, “Generalized localization for spherical partial sums of multiple Fourier series,” J. Fourier Anal. Appl., 25, No. 6, 3174–3183 (2019).
R. R. Ashurov, “Generalized localization for spherical partial sums of multiple Fourier series,” Dokl. RAN, 489, 7–10 (2019).
R. R. Ashurov, A. Ahmedov, and B. Mahmud Ahmad Rodzi, “The generalized localization for multiple Fourier integrals,” J. Math. Anal. Appl., 371, 832–841 (2010).
R. R. Ashurov and A. Butaev, “On generalized localization of Fourier inversion for distributions,” In: Topics in Functional Analysis and Algebra, USA–Uzbekistan Conf. on Anal. and Math. Phys., California State Univ., Fullerton, USA, May 20–23, 2014, American Mathematical Society, Providence, pp. 33–50 (2016).
R. R. Ashurov and K. T. Buvaev, “Summability almost everywhere of multiple Fourier integrals,” Diff. Uravn., 53, 750–760 (2017).
R. R. Ashurov and A. Butaev, “On pointwise convergence of continuous wavelet transforms,” Uzb. Math. J., 1, 2–24 (2018).
R. R. Ashurov, A. Butaev, and B. Pradhan, “On generalized localization of Fourier inversion associated with an elliptic operator for distributions,” Abstr. Appl. Anal., 2012, 649848 (2012).
R. R. Ashurov and Yu. E. Fayziev, “Generalized localization principle for continuous wavelet expansions,” Mat. Zametki, 106, 75–81 (2019).
K. I. Babenko, “On summability and convergence of expansions in eigenfunctions of a differential operator,” Mat. Sb., 91, 147–201 (1973).
A. Y. Bastis, “Generalized localization principle for N-fold Fourier integral,” Dokl. AN SSSR, 278, 777–778 (1984).
A. Y. Bastis, “Generalized localization for Fourier series in eigenfunctions of the Laplace operator in the Lp classes,” Litov. Mat. Sb., 31, 387–405 (1991).
I. L. Bloshanskiy, “On uniform convergence of trigonometric series and Fourier integrals,” Mat. Zametki, 18, 675–684 (1975).
A. Carbery, E. Romera, and F. Soria, “Radial weights and mixed norm inequalities for the disc multiplier,” J. Funct. Anal., 109, 52–75 (1992).
A. Carbery, J. L. Rubio de Francia, and L. Vega, “Almost everywhere summability of Fourier integrals,” J. London Math. Soc. (2), 38, 513–524 (1988).
A. Carbery and F. Soria, “Almost everywhere convergence of Fourier integrals for functions in Sobolev spaces, and an L2-localization principle,” Rev. Mat. Iberoam., 4, 319–337 (1988).
A. Carbery and F. Soria, “Pointwise Fourier inversion and localization in Rn,” J. Fourier Anal. Appl., 3, Special Issue, 847–858 (1997).
L. Carleson, “On convergence and growth of partial sums of Fourier series,” Acta Math., 116, 135–157 (1966).
C. Fefferman, “On the divergence of multiple Fourier series,” Bull. Am. Math. Soc., 77, 191–195 (1971).
L. Grafakos, Classical Fourier Analysis, Springer, New York (2008).
R. A. Hunt, “On convergence of Fourier series,” Proc. Conf. on Orthogonal Expansions and Their Continuous Analogues, Univ. Press, Edwardsville–Carbondale, pp. 235–255 (1968).
V. A. Il’in, “On generalized interpretation of the localization principle for Fourier series in fundamental systems of functions,” Sib. Mat. Zh., 9, No. 5, 1093–1106 (1968).
C. E. Kenig and P. A. Tomas, “Maximal operators defined by Fourier multipliers,” Studia Math., 68, 79–83 (1980).
S. Lee, “Improved bounds for Bochner–Riesz and maximal Bochner–Riesz operators,” Duke Math. J., 122, 205–232 (2004).
Sh. Lu, “Conjectures and problems in Bochner–Riesz means,” Front. Math. China., 8, 1237–1251 (2013).
J. Mitchell, “On the summability of multiple orthogonal series,” Trans. Am. Math. Soc., 71, 136–151 (1951).
B. Randol, “On the asymptotic behavior of the Fourier transform of the indicator function of the convex set,” Trans. Am. Math. Soc., 139, 279–285 (1969).
P. Sjölin, “Convergence almost everywhere of certain singular integrals and multiple Fourier series,” Ark. Mat., 9, 65–90 (1971).
P. Sjölin, “Regularity and integrability of spherical means,” Monatsh. Math., 96, 277–291 (1983).
E. M. Stein, “Localization and summability of multiple Fourier series,” Acta Math., 1-2, 93–147 (1958).
E. M. Stein, “On limits of sequences of operators,” Ann. Math., 74, 140–170 (1961).
E. M. Stein, “Some problems in harmonic analysis,” In: Harmonic Analysis in Euclidean Spaces. Part 1, Am. Math. Soc., Providence, pp. 3–20 (1978).
E. M. Stein and G. Weiss, Introduction to Fourier Analysis on Euclidean Spaces, Princeton University Press, Princeton (1971).
T. Tao, “The weak-type endpoint Bochner–Riesz conjecture and related topics,” Indiana Univ. Math. J., 47, 1097–1124 (1998).
T. Tao, “On the maximal Bochner–Riesz conjecture in the plane for p < 2,” Trans. Am. Math. Soc., 354, 1947–1959 (2002).
Author information
Authors and Affiliations
Corresponding author
Additional information
Translated from Sovremennaya Matematika. Fundamental’nye Napravleniya (Contemporary Mathematics. Fundamental Directions), Vol. 67, No. 4, Science — Technology — Education — Mathematics — Medicine, 2022.
Rights and permissions
Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.
About this article
Cite this article
Ashurov, R.R. Generalized Localization and Summability Almost Everywhere of Multiple Fourier Series and Integrals. J Math Sci 278, 408–425 (2024). https://doi.org/10.1007/s10958-024-06930-7
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10958-024-06930-7