Czechoslovak Mathematical Journal, first online, pp. 1-13


The Fourier transform in Lebesgue spaces

Erik Talvila

Received January 1, 2023.   Published online March 6, 2024.

Abstract:  For each $f\in L^p({\mathbb R)}$ ($1\leq p<\infty$) it is shown that the Fourier transform is the distributional derivative of a Hölder continuous function. For each $p$, a norm is defined so that the space of Fourier transforms is isometrically isomorphic to $L^p({\mathbb R)}$. There is an exchange theorem and inversion in norm.
Keywords:  Fourier transform; Lebesgue space; tempered distribution; generalised function; Banach space; continuous primitive integral
Classification MSC:  42A38, 46F10, 26A42, 46B04

PDF available at:  Springer   Institute of Mathematics CAS

References:
[1] A. A. Abdelhakim: On the unboundedness in $L^q$ of the Fourier transform of $L^p$ functions. Available at https://arxiv.org/abs/1806.03912 (2020), 8 pages. DOI 10.48550/arXiv.1806.03912
[2] K. I. Babenko: An inequality in the theory of Fourier integrals. Izv. Akad. Nauk SSSR, Ser. Mat. 25 (1961), 531-542. (In Russian.) MR 0138939 | Zbl 0122.34404
[3] W. Beckner: Inequalities in Fourier analysis. Ann. Math. (2) 102 (1975), 159-182. DOI 10.2307/1970980 | MR 0385456 | Zbl 0338.42017
[4] S. Bochner: Lectures on Fourier Integrals. Annals of Mathematics Studies 42. Princeton University Press, Princeton (1959). DOI 10.1515/9781400881994 | MR 0107124 | Zbl 0085.31802
[5] W. F. Donoghue, Jr.: Distributions and Fourier Transforms. Pure and Applied Mathematics 32. Academic Press, New York (1969). MR 3363413 | Zbl 0188.18102
[6] A. Erdélyi, W. Magnus, F. Oberhettinger, F. G. Tricomi: Tables of Integral Transforms. Vol. I. McGraw-Hill, New York (1954). MR 0061695 | Zbl 0055.36401
[7] G. B. Folland: Real Analysis: Modern Techniques and Their Applications. John Wiley, New York (1999). MR 1681462 | Zbl 0924.28001
[8] F. G. Friedlander: Introduction to the Theory of Distributions. Cambridge University Press, Cambridge (1998). MR 1721032 | Zbl 0971.46024
[9] L. Grafakos: Classical Fourier Analysis. Graduate Texts in Mathematics 249. Springer, New York (2008). DOI 10.1007/978-0-387-09432-8 | MR 2445437 | Zbl 1220.42001
[10] E. H. Lieb, M. Loss: Analysis. Graduate Studies in Mathematics 14. AMS, Providence (2001). DOI 10.1090/gsm/014 | MR 1817225 | Zbl 0966.26002
[11] R. M. McLeod: The Generalized Riemann Integral. The Carus Mathematical Monographs 20. The Mathematical Association of America, Washington (1980). DOI 10.5948/UPO9781614440208 | MR 0588510 | Zbl 0486.26005
[12] E. M. Stein, G. Weiss: Introduction to Fourier Analysis on Euclidean Spaces. Princeton Mathematical Series 32. Princeton University Press, Princeton (1971). MR 0304972 | Zbl 0232.42007
[13] E. Talvila: The distributional Denjoy integral. Real Anal. Exch. 33 (2007/08), 51-82. DOI 10.14321/realanalexch.33.1.0051 | MR 2402863 | Zbl 1154.26011
[14] E. Talvila: Fourier transform inversion using an elementary differential equation and a contour integral. Am. Math. Mon. 126 (2019), 717-727. DOI 10.1080/00029890.2019.1632629 | MR 4009888 | Zbl 1422.42007
[15] E. C. Titchmarsh: A contribution to the theory of Fourier transforms. Proc. Lond. Math. Soc. (2) 23 (1924), 279-289. DOI 10.1112/plms/s2-23.1.279 | MR 1575191 | JFM 50.0201.02

Affiliations:   Erik Talvila Department of Mathematics & Statistics, University of the Fraser Valley, 33844 King Road, Abbotsford, BC Canada V2S 7M8, e-mail: Erik.Talvila@ufv.ca


 
PDF available at: