Abstract
Necessary and sufficient conditions for a function \(f\) to belong to the generalized Lipschitz classes \(H^{m,\omega}_{q,\nu}\) and \(h^{m,\omega}_{q,\nu}\) for fractional \(m\) are given in terms of its \(q\)-Bessel–Fourier transform \(\mathcal F_{q,\nu}(f)\). Dual results are considered as well. An analog of the Titchmarsh theorem for fractional-order differences is proved.
Similar content being viewed by others
References
P. L. Butzer and R. J. Nessel, Fourier Analysis and Approximation, in Pure and Appl. Math. (Academic Press, New York–London, 1971), Vol. 40.
N. K. Bary and S. B. Stechkin, “Best approximations and differential properties of two conjugate functions,” in Tr. Mosk. Mat. Obs. (GITTL, Moscow, 1956), Vol. 5, pp. 483–522.
F. Móricz, “Absolutely convergent Fourier integrals and classical function spaces,” Arch. Math. (Basel) 91 (1), 49–62 (2008).
S. S. Volosivets, “Fourier transforms and generalized Lipschitz classes in uniform metric,” J. Math. Anal. Appl. 383 (2), 344–352 (2011).
R. P. Boas, Integrability Theorems for Trigonometric Transforms (Springer- Verlag, New York, 1967).
F. Móricz, “Absolutely convergent Fourier series and function classes,” J. Math. Anal. Appl. 324 (2), 1168–1177 (2006).
S. Tikhonov, “Smoothness conditions and Fourier series,” Math. Inequal. Appl. 10 (2), 229–242 (2007).
E. M. Berkak, E. M. Loualid, and R. Daher, “Boas-type theorems for the \(q\)-Bessel Fourier transform,” Anal. Math. Phys. 11 (3) (2021).
E. Titchmarsh, Introduction to the Theory of Fourier Integrals (Chelsea Publishing Co., New York, 1986).
A. Achak, R. Daher, L. Dhaouadi, and E. M. Loualid, “An analog of Titchmarsh’s theorem for the \(q\)-Bessel transform,” Ann. Univ. Ferrara Sez. VII Sci. Mat. 65 (1), 1–13 (2019).
G. Gasper and M. Rahman, Basic Hypergeometric Series, in Encyclopedia of Math. and Its Appl. (Cambridge Univ. Press, Cambridge, 1990), Vol. 35.
V. Kac and P. Cheung, Quantum Calculus (Springer, New York, 2002).
T. H. Koornwinder and R. F. Swarttouw, “On \(q\)-analogues of the Fourier and Hankel transforms,” Trans. Amer. Math. Soc. 333 (1), 445–461 (1992).
L. Dhaouadi, A. Fitouhi, and J. El Kamel, “Inequalities in \(q\)-Fourier analysis,” JIPAM. J. Inequal. Pure Appl. Math. 7 (5), 171 (2006).
L. Dhaouadi, “On the \(q\)-Bessel Fourier transform,” Bull. Math. Anal. Appl. 5 (2), 42–60 (2013).
A. Fitouhi and L. Dhaouadi, “Positivity of the generalized translation associated with the \(q\)-Hankel transform,” Constr. Approx. 34 (3), 435–472 (2011).
M. Izumi and S.-I. Izumi, “Lipschitz classes and Fourier coefficients,” J. Math. Mech. 18 (9), 857–870 (1969).
Acknowledgments
We express our gratitude to the referee for valuable remarks, which have helped us to improve the exposition.
Funding
The first author’s research was supported by the Development Program of the Regional Scientific-Educational Center “Mathematics for Future Technology” (project no. 075-02-2023-949).
Author information
Authors and Affiliations
Corresponding author
Additional information
Translated from Matematicheskie Zametki, 2023, Vol. 114, pp. 68–80 https://doi.org/10.4213/mzm13467.
Rights and permissions
About this article
Cite this article
Volosivets, S.S., Krotova, Y.I. Boas and Titchmarsh Type Theorems for Generalized Lipschitz Classes and \(q\)-Bessel Fourier Transform. Math Notes 114, 55–65 (2023). https://doi.org/10.1134/S0001434623070052
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S0001434623070052