|Died||4 September 1969 (aged 82)|
|Known for||Riesz–Thorin theorem|
M. Riesz extension theorem
F. and M. Riesz theorem
|Doctoral advisor||Lipót Fejér|
|Doctoral students||Harald Cramér|
Einar Carl Hille
Marcel Riesz (Hungarian: Riesz Marcell [ˈriːs ˈmɒrt͡sɛll]; 16 November 1886 – 4 September 1969) was a Hungarian mathematician, known for work on summation methods, potential theory, and other parts of analysis, as well as number theory, partial differential equations, and Clifford algebras. He spent most of his career in Lund (Sweden).
Marcel Riesz was born in Győr, Austria-Hungary; he was the younger brother of the mathematician Frigyes Riesz. He obtained his PhD at Eötvös Loránd University under the supervision of Lipót Fejér. In 1911, he moved to Sweden upon the invitation of Gösta Mittag-Leffler. From 1911 to 1925 he taught at Stockholms högskola (now Stockholm University). From 1926 to 1952 he was professor at Lund University. After retiring, he spent 10 years at universities in the United States. He returned to Lund in 1962, and died there in 1969.
The work of Riesz as a student of Fejér in Budapest was devoted to trigonometric series:
One of his results states that, if
His results on summability of trigonometric series include a generalisation of Fejér's theorem to Cesàro means of arbitrary order. He also studied the summability of power and Dirichlet series, and coauthored a book Hardy & Riesz (1915) on the latter with G.H. Hardy.
Part of the analytic work of Riesz in the 1920s used methods of functional analysis.
In the early 1920s, he worked on the moment problem, to which he introduced the operator-theoretic approach by proving the Riesz extension theorem (which predated the closely related Hahn–Banach theorem).
Later, he devised an interpolation theorem to show that the Hilbert transform is a bounded operator in Lp (1 < p < ∞). The generalisation of the interpolation theorem by his student Olaf Thorin is now known as the Riesz–Thorin theorem.
Riesz also established, independently of Andrey Kolmogorov, what is now called the Kolmogorov–Riesz compactness criterion in Lp: a subset K ⊂Lp(Rn) is precompact if and only if the following three conditions hold: (a) K is bounded;
(b) for every ε > 0 there exists R > 0 so that
for every f ∈ K;
(c) for every ε > 0 there exists ρ > 0 so that
for every y ∈ Rn with |y| < ρ, and every f ∈ K.
Potential theory, PDE, and Clifford algebras
After 1930, the interests of Riesz shifted to potential theory and partial differential equations. He made use of "generalised potentials", generalisations of the Riemann–Liouville integral. In particular, Riesz discovered the Riesz potential, a generalisation of the Riemann–Liouville integral to dimension higher than one.
In the 1940s and 1950s, Riesz worked on Clifford algebras. His 1958 lecture notes, the complete version of which was only published in 1993 (Riesz (1993)), were dubbed by the physicist David Hestenes "the midwife of the rebirth" of Clifford algebras.
- Hardy, G. H.; Riesz, M. (1915). The general theory of Dirichlet's series. Cambridge University Press. JFM 45.0387.03.
- Riesz, Marcel (1988). Collected papers. Berlin, New York: Springer-Verlag. ISBN 978-3-540-18115-6. MR 0962287.
- Riesz, Marcel (1993) . Clifford numbers and spinors. Fundamental Theories of Physics. 54. Dordrecht: Kluwer Academic Publishers Group. ISBN 978-0-7923-2299-3. MR 1247961.
- Gårding, Lars (1970). "Marcel Riesz in memoriam". Acta Mathematica. 124: x–xi. doi:10.1007/BF02394565. ISSN 0001-5962. MR 0256837.
- Peetre, Jaak (1988). Function spaces and applications (Lund, 1986). Lecture Notes in Math. 1302. Berlin: Springer. pp. 1–10. doi:10.1007/BFb0078859. MR 0942253.
- Horváth, Jean (1982). "L'œuvre mathématique de Marcel Riesz. I" [The mathematical work of Marcel Riesz. I]. Proceedings of the Seminar on the History of Mathematics (in French). 3: 83–121. MR 0651728.
- Theorem III.5.1 in Zygmund, Antoni (1968). Trigonometric series (2nd ed.). Cambridge University Press (published 1988). ISBN 978-0-521-35885-9. MR 0933759.
- Horvath, Jean. "L'œuvre mathématique de Marcel Riesz. II" [The mathematical work of Marcel Riesz. II]. Proceedings of the Seminar on the History of Mathematics (in French). 4: 1–59. MR 0704360. Zbl 0508.01015.
- §14.32 in Titchmarsh, E. C. (1986). The theory of the Riemann zeta-function (Second ed.). New York: The Clarendon Press, Oxford University Press. ISBN 0-19-853369-1. MR 0882550.
- Putnam, C. R. (1980). "The F. and M. Riesz theorem revisited". Integral Equations Operator Theory. 3 (4): 508–514. doi:10.1007/bf01702313. MR 0595749.
- Kjeldsen, Tinne Hoff (1993). "The early history of the moment problem". Historia Math. 20 (1): 19–44. doi:10.1006/hmat.1993.1004. MR 1205676.
- Akhiezer, N. I. (1965). The Classical Moment Problem and Some Related Questions in Analysis. Oliver & Boyd.
- Gårding, Lars. Some points of analysis and their history. University Lecture Series. 11. Providence, RI: American Mathematical Society. pp. 31–35. ISBN 0-8218-0757-9. MR 1469493.
- Hanche-Olsen, Harald; Holden, Helge (2010). "The Kolmogorov–Riesz compactness theorem". Expositiones Mathematicae. 28 (4): 385–394. arXiv:0906.4883. doi:10.1016/j.exmath.2010.03.001. MR 2734454.
- Hestenes, David (2011). "Grassmann's legacy". In Petsche, Hans-Joachim; Lewis, Albert C.; Liesen, Jörg; Russ, Steve. From Past to Future: Graßmann's Work in Context Graßmann Bicentennial Conference (PDF). Springer. Archived from the original (PDF) on 2012-03-16.