János Aczél (mathematician)

János Dezső Aczél FRSC (Hungarian: [ˈɒt͡seːl]; 26 December 1924 – 1 January 2020),[1][2] also known as John Aczel,[3] was a Hungarian-Canadian mathematician, who specialized in functional equations and information theory.

János Aczél
János Aczél mathematician 1970.jpg
Aczél in 1970
János Dezső Aczél

(1924-12-26)26 December 1924
Died1 January 2020(2020-01-01) (aged 95)
Spouse(s)Zsuzsanna Kende
Scientific career
Fieldsfunctional equations
information theory
InstitutionsUniversity of Waterloo
University of Cologne
University of Debrecen
University of Miskolc
University of Szeged
InfluencesFrigyes Riesz
Lipót Fejér

Professional careerEdit

Aczél earned a doctorate in mathematical analysis from the University of Budapest, and held positions at the University of Cologne, Kossuth University, University of Miskolc, and University of Szeged.[4] He joined the University of Waterloo faculty in 1965, eventually becoming Distinguished Professor in the Department of Pure Mathematics.[5]

He was the founder of the journal Aequationes Mathematicae, first published in 1968, and remained its honorary editor-in-chief.[6]

Awards and honorsEdit

Aczél held honorary degrees from the University of Karlsruhe, the University of Graz, and the University of Silesia in Katowice.[4] In 1971, he was elected a fellow of the Royal Society of Canada.[7] In 1990 he became an external member of the Hungarian Academy of Sciences.[1] In 2008 he became an honorary member of the Hamburg Mathematical Society, the oldest active mathematical society in the world.[8]

He was the 1988 winner of the Santiago Ramón y Cajal Medal.[4] In 2004 he won the Kampé de Fériet Award of the annual Information Processing and Management of Uncertainty conference, "for his pioneering work on the theory of functional equations, with applications in many fields, such as information measures, index numbers, group decision making, aggregation, production functions, laws of science, theory of measurement and utility theory."[9]

Issues of the journal Aequationes Mathematicae were dedicated to Aczél in 1999, 2005, and 2010, in honor of his 75th, 80th, and 85th birthdays. He died six days after his 95th birthday in 2020.[10][11][12]


Aczél was the author or co-author of:

  • Aczél, J.; Gołąb, S. (1960), Funktionalgleichungen der Theorie der geometrischen Objekte, Polska Akademia Nauk. Monografie Matematyczne, Tom 39, Państwowe Wydawnictwo Naukowe, Warsaw, MR 0133763.[13]
  • Aczél, J. (1966), Lectures on functional equations and their applications, Mathematics in Science and Engineering, 19, New York: Academic Press, MR 0208210. Previously published in German as Vorlesungen über Funktionalgleichungen und ihre Anwendungen (Birkhäuser, 1961).[14][15][16]
  • Aczél, J.; Daróczy, Z. (1975), On measures of information and their characterizations, Mathematics in Science and Engineering, 115, New York: Academic Press [Harcourt Brace Jovanovich Publishers], MR 0689178.[17]
  • Aczél, J. (1987), A short course on functional equations, Theory and Decision Library. Series B: Mathematical and Statistical Methods, Dordrecht: D. Reidel Publishing Co., doi:10.1007/978-94-009-3749-9, ISBN 90-277-2376-1.[18]
  • Aczél, J.; Dhombres, J. (1989), Functional equations in several variables, Encyclopedia of Mathematics and its Applications, 31, Cambridge: Cambridge University Press, doi:10.1017/CBO9781139086578, ISBN 0-521-35276-2.[19]


  1. ^ a b Member listing, Hungarian Academy of Sciences, accessed 25 January 2013.
  2. ^ We remember Distinguished Professor Emeritus János Aczel, University of Waterloo
  3. ^ [1]
  4. ^ a b c Biography as a speaker at the Marschak Colloquium at UCLA, 1999, accessed 25 January 2013.
  5. ^ Emeritus/Adjunct faculty, Pure Mathematics, Waterloo, accessed 25 January 2013.
  6. ^ Editorial board of Aequationes Mathematicae, accessed 25 January 2013.
  7. ^ RSC Fellow listing, accessed 25 January 2013.
  8. ^ János Aczél's Latest Honour, Hungarian Academy of Sciences, accessed 25 January 2013.
  9. ^ Kampé de Fériet Award, IPMU, accessed 25 January 2013.
  10. ^ Luce, R. Duncan (1999), "Personal reflections on an unintentional behavioral scientist", Aequationes Mathematicae, 58 (1–2): 3–15, doi:10.1007/s000100050088.
  11. ^ Ebanks, Bruce; Ng, Che Tat (2005), "Tribute to a distinguished Professor: János Aczél at 80", Aequationes Mathematicae, 69 (1–2): 1–5, doi:10.1007/s00010-004-2769-z, MR 2126180.
  12. ^ Ng, Che Tat (2010), "Tribute to a distinguished Professor János Aczél at 85", Aequationes Mathematicae, 80 (1–2): 1–4, doi:10.1007/s00010-010-0052-z, MR 2736935.
  13. ^ Review of Funktionalgleichungen der Theorie der geometrischen Objekte by Albert Nijenhuis, MR0133763.
  14. ^ Review of Vorlesungen über Funktionalgleichungen und ihre Anwendungen by Marek Kuczma, MR0124647.
  15. ^ Review of Lectures on functional equations and their applications by M. Hosszú, MR0208210.
  16. ^ Review of Lectures on Functional Equations and their Applications by Frank Hahn (1968), American Mathematical Monthly 75 (3): 314, doi:10.2307/2314998.
  17. ^ Review of On measures of information and their characterizations by J. Kampé de Fériet (1977), Bulletin of the American Mathematical Society 83 (2): 192–196, doi:10.1090/S0002-9904-1977-14257-2.
  18. ^ Review of A short course on functional equations by Dale K. Osborne, MR0875412.
  19. ^ Review of Functional equations in several variables by K. Lajkó, MR1004465.

External linksEdit