Béla Szőkefalvi-Nagy

Portrait of Béla Szőkefalvi-Nagy

Béla Szőkefalvi-Nagy (29 July 1913, Kolozsvár – 21 December 1998, Szeged) was a Hungarian mathematician. His father, Gyula Szőkefalvi-Nagy was also a famed mathematician. Szőkefalvi-Nagy collaborated with Alfréd Haar and Frigyes Riesz, founders of the Szegedian school of mathematics. He contributed to the theory of Fourier series and approximation theory. His most important achievements were made in functional analysis, especially, in the theory of Hilbert space operators. He was editor-in-chief of the Zentralblatt für Mathematik, the Acta Scientiarum Mathematicarum, and the Analysis Mathematica. He was awarded the Lomonosov Medal in 1979: the Béla Szőkefalvi-Nagy Medal honoring his memory is awarded yearly by Bolyai Institute.

His books

• Béla Szőkefalvi-Nagy: Spektraldarstellung linearer Transformationen des Hilbertschen Raumes.(German) Berlin, 1942. 80 p.; 1967. 82 p.
• Frederic Riesz, Béla Szőkefalvi-Nagy: Leçons d'analyse fonctionnelle. (French) 2e éd. Akadémiai Kiado, Budapest, 1953, VIII+455 pp.
• Ciprian Foiaş, Béla Szőkefalvi-Nagy: Analyse harmonique des opérateurs de l'espace de Hilbert. (French) Masson et Cie, Paris; Akadémiai Kiadó, Budapest 1967 xi+373 pp.
• Béla Szőkefalvi-Nagy, Frederic Riesz: Funkcionálanalízis. Budapest, 1988. 534 p. (English: Functional Analysis (1990). Dover. ISBN 0-486-66289-6)

His articles

• Diagonalization of matrices over H^∞. Acta Scientiarum Mathematicarum. Szeged, 1976
• On contractions similar to isometries and Toeplitz operators, with Ciprian Foiaş. Ann. Acad. Scient. Fennicae, 1976.
• The function model of a contraction and the space L’/H’, with Ciprian Foiaş. Acta Scientiarum Mathematicarum. Szeged, 1979, 1980.
• Toeplitz type operators and hyponormality, with Ciprian Foiaş. Operator theory. Advances and appl., 1983.
• Factoring compact operator-valued functions, with authors. Acta Scientiarum Mathematicarum. Szeged, 1985.

See also

• Sz.-Nagy's dilation theorem
• Erdős-Nagy theorem

To the memory of Béla Szőkefalvi-Nagy

• Operator theory: advances and applications. Recent advances in operator theory and related topics : the Béla Szökefalvi-Nagy memorial volume : [memorial conference held August 2–6, 1999 in Szeged] / eds. László Kérchy et al. Basel ; Boston ; Berlin : Birkhäuser Verlag, 2001. XLIX, 670 p. (Operator theory : advances and applications ; 127.) ISBN 3-7643-6607-9

References

• D.P. Zhelobenko, Bela Szokefalvi-Nagy (obituary), Russian Mathematical Surveys 54 (1999), 819-822.
• Szôkefalvi-Nagy Béla (in Hungarian)