Uniformly convergent Fourier series and multiplication of functions
Trudy Matematicheskogo Instituta imeni V.A. Steklova, Harmonic analysis, approximation theory, and number theory, Tome 303 (2018), pp. 186-192

Voir la notice du chapitre de livre provenant de la source Math-Net.Ru

Let $U(\mathbb T)$ be the space of all continuous functions on the circle $\mathbb T$ whose Fourier series converges uniformly. Salem's well-known example shows that a product of two functions in $U(\mathbb T)$ does not always belong to $U(\mathbb T)$ even if one of the factors belongs to the Wiener algebra $A(\mathbb T)$. In this paper we consider pointwise multipliers of the space $U(\mathbb T)$, i.e., the functions $m$ such that $mf\in U(\mathbb T)$ whenever $f\in U(\mathbb T)$. We present certain sufficient conditions for a function to be a multiplier and also obtain some Salem-type results.
Keywords: uniformly convergent Fourier series, function spaces, multiplication operators.
V. V. Lebedev. Uniformly convergent Fourier series and multiplication of functions. Trudy Matematicheskogo Instituta imeni V.A. Steklova, Harmonic analysis, approximation theory, and number theory, Tome 303 (2018), pp. 186-192. http://geodesic.mathdoc.fr/item/TM_2018_303_a13/
@article{TM_2018_303_a13,
     author = {V. V. Lebedev},
     title = {Uniformly convergent {Fourier} series and multiplication of functions},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {186--192},
     year = {2018},
     volume = {303},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/TM_2018_303_a13/}
}
TY  - JOUR
AU  - V. V. Lebedev
TI  - Uniformly convergent Fourier series and multiplication of functions
JO  - Trudy Matematicheskogo Instituta imeni V.A. Steklova
PY  - 2018
SP  - 186
EP  - 192
VL  - 303
UR  - http://geodesic.mathdoc.fr/item/TM_2018_303_a13/
LA  - ru
ID  - TM_2018_303_a13
ER  - 
%0 Journal Article
%A V. V. Lebedev
%T Uniformly convergent Fourier series and multiplication of functions
%J Trudy Matematicheskogo Instituta imeni V.A. Steklova
%D 2018
%P 186-192
%V 303
%U http://geodesic.mathdoc.fr/item/TM_2018_303_a13/
%G ru
%F TM_2018_303_a13

[1] J.-P. Kahane, Séries de Fourier absolument convergentes, Springer, Berlin, 1970 | MR

[2] A. N. Kolmogorov, S. V. Fomin, Elements of the Theory of Functions and Functional Analysis, Dover Publ., Mineola, NY, 1999 | MR | MR

[3] V. V. Lebedev, “On uniform convergence of Fourier series”, Math. Notes, 91:6 (2012), 889–892 | DOI | DOI | MR | Zbl

[4] N. K. Bari, A Treatise on Trigonometric Series, Pergamon, New York, 1964 | MR

[5] A. M. Olevskii, “On the algebra of functions generated by uniformly convergent Fourier series”, Sov. Math., Dokl., 36:3 (1988), 542–544 | MR

[6] S. A. Vinogradov, M. G. Goluzina, V. P. Khavin, “Multipliers and divisors of Cauchy–Stieltjes integrals”, Semin. Math., V.A. Steklov Math. Inst., Leningrad, 19, 1972, 29–42 | MR | Zbl