Sigurður Helgason (mathematician)

Sigurdur Helgason (Icelandic: Sigurður Helgason; 30 September 1927 – 3 December 2023) was an Icelandic mathematician whose research has been devoted to the geometry and analysis on symmetric spaces. In particular, he used new integral geometric methods to establish fundamental existence theorems for differential equations on symmetric spaces as well as some new results on the representations of their isometry groups. He also introduced a Fourier transform on these spaces and proved the principal theorems for this transform, the inversion formula, the Plancherel theorem and the analog of the Paley–Wiener theorem.

Sigurdur Helgason
Sigurdur Helgason
Helgason in 1988
Born(1927-09-30)30 September 1927
Died3 December 2023(2023-12-03) (aged 96)
OccupationMathematician
HonorsAMS fellow (2013)
Leroy P. Steele Prize (1988)
AAA&S member (1970)
Scientific career
Doctoral advisorSalomon Bochner

Biography

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Sigurdur Helgason was born in Akureyri, Iceland on 30 September 1927. In 1954, he earned a PhD from Princeton University under Salomon Bochner. Helgason became a professor of mathematics at the Massachusetts Institute of Technology in 1965,[1] and he retired from the faculty in 2014.[2]

Helgason received the Børge Jessen Diploma Award of the Danish Mathematical Society in 1982, and the Grand Knight's Cross (Stórriddarakross) of the Icelandic Order of the Falcon in 1991.[2][3] He was winner of the 1988 Leroy P. Steele Prize for Seminal Contributions for his books Groups and Geometric Analysis and Differential Geometry, Lie Groups and Symmetric Spaces.[4] This was followed by the 2008 book Geometric Analysis on Symmetric Spaces. On 31 May 1996, Helgason received an honorary doctorate from the Faculty of Science and Technology at Uppsala University, Sweden.[5]

Helgason was elected a member of the Icelandic Academy of Sciences [is] in 1960, the American Academy of Arts and Sciences in 1970,[6] and the Royal Danish Academy of Sciences and Letters in 1972.[7][3] In 2013, he became a fellow of the American Mathematical Society.[8] He was made an honorary member of the Icelandic Mathematical Society when he turned 70, and a symposium was held in his honor.[3]

Helgason died on 3 December 2023, at the age of 96.[9]

Selected works

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Articles

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Books

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References

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  1. ^ "Sigurdur Helgason, Professor Emeritus of Mathematics, Dies at 96", math.mit.edu, MIT Department of Mathematics, 6 December 2023, retrieved 2 April 2024
  2. ^ a b "Reports to the President For the Year Ended June 30, 2014, School of Science, Department of Mathematics: Retirements and Departures" (PDF), web.mit.edu, MIT, retrieved 2 April 2024
  3. ^ a b c "Íslenska stærðfræðafélagið: Heiðursfélagar" [Icelandic Mathematical Society: Honorary Members], stae.is (in Icelandic), Icelandic Mathematical Society, retrieved 2 April 2024
  4. ^ "1988 Leroy P. Steele Prize winners", ams.org, AMS, retrieved 2 April 2024
  5. ^ "Honorary doctorates - Uppsala University, Sweden". Uppsala University. 9 June 2023. Retrieved 2 April 2024.
  6. ^ "Members: Professor Sigurður Helgason", royalacademy.dk, Royal Danish Academy of Sciences and Letters, archived from the original on 8 August 2022
  7. ^ "Member directory: Sigurdur Helgason", amacad.org, AAA&S, retrieved 2 April 2024
  8. ^ "List of Fellows of the American Mathematical Society", ams.org, AMS, retrieved 21 January 2013
  9. ^ "Andlát: Sigurður Helgason". mbl.is (in Icelandic). Morgunblaðið. 5 December 2023. Retrieved 10 December 2023.
  10. ^ Auslander, Louis (1964). "Review: Differential geometry and symmetric spaces, by S. Helgason". Bull. Amer. Math. Soc. 70 (2): 227–229. doi:10.1090/S0002-9904-1964-11091-0.
  11. ^ Kulkarni, Ravi S. (1980). "Review: Differential geometry, Lie groups and symmetric spaces, by S. Helgason". Bull. Amer. Math. Soc. (N.S.). 2 (3): 468–476. doi:10.1090/S0273-0979-1980-14772-2.
  12. ^ Howe, Roger (1989). "Groups and geometric analysis. Integral geometry, invariant differential operators and spherical functions, by S. Helgason". Bull. Amer. Math. Soc. (N.S.). 20 (2): 252–256. doi:10.1090/S0273-0979-1989-15786-8.
  13. ^ Rouvière, François (1995). "Geometric analysis on symmetric spaces, by S. Helgason". Bull. Amer. Math. Soc. (N.S.). 32 (4): 441–446. doi:10.1090/S0273-0979-1995-00602-6.

Sources

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