André Weil (/veɪl/; French: [ɑ̃dʁe vɛjl]; 6 May 1906 – 6 August 1998) was an influential French mathematician of the 20th century,^{[3]} known for his foundational work in number theory and algebraic geometry. He was a founding member and the de facto early leader of the Bourbaki group. The philosopher Simone Weil was his sister.^{[4]}^{[5]}
Life
André Weil was born in Paris to Alsatian agnostic Jewish parents who fled the annexation of AlsaceLorraine by the German Empire after the FrancoPrussian War in 1870–71. The famous philosopher Simone Weil was Weil's only sibling. He studied in Paris, Rome and Göttingen and received his doctorate in 1928. While in Germany, Weil befriended Carl Ludwig Siegel. Starting in 1930, he spent two academic years at Aligarh Muslim University. Aside from mathematics, Weil held lifelong interests in classical Greek and Latin literature, in Hinduism and Sanskrit literature: he taught himself Sanskrit in 1920.^{[6]}^{[7]} After teaching for one year in AixMarseille University, he taught for six years in Strasbourg. He married Éveline in 1937.
Weil was in Finland when World War II broke out; he had been traveling in Scandinavia since April 1939. His wife Éveline returned to France without him. Weil was mistakenly arrested in Finland at the outbreak of the Winter War on suspicion of spying; however, accounts of his life having been in danger were shown to be exaggerated.^{[8]} Weil returned to France via Sweden and the United Kingdom, and was detained at Le Havre in January 1940. He was charged with failure to report for duty, and was imprisoned in Le Havre and then Rouen. It was in the military prison in BonneNouvelle, a district of Rouen, from February to May, that Weil completed the work that made his reputation. He was tried on 3 May 1940. Sentenced to five years, he requested to be attached to a military unit instead, and was given the chance to join a regiment in Cherbourg. After the fall of France, he met up with his family in Marseille, where he arrived by sea. He then went to ClermontFerrand, where he managed to join his wife Éveline, who had been living in Germanoccupied France.
In January 1941, Weil and his family sailed from Marseille to New York. He spent the remainder of the war in the United States, where he was supported by the Rockefeller Foundation and the Guggenheim Foundation. For two years, he taught undergraduate mathematics at Lehigh University, where he was unappreciated, overworked and poorly paid. But, he hated Lehigh very much for their heavy teaching workload and he swore that he would never talk about "Lehigh" any more.^{[citation needed]} He quit the job at Lehigh, and then he moved to Brazil and taught at the Universidade de São Paulo from 1945 to 1947, where he worked with Oscar Zariski. He then returned to the United States and taught at the University of Chicago from 1947 to 1958, before moving to the Institute for Advanced Study, where he would spend the remainder of his career. He was a Plenary Speaker at the ICM in 1950 in Cambridge, Massachusetts,^{[9]} in 1954 in Amsterdam, and in 1978 in Helsinki. In 1979, Weil shared the second Wolf Prize in Mathematics with Jean Leray.
Work
Weil made substantial contributions in a number of areas, the most important being his discovery of profound connections between algebraic geometry and number theory. This began in his doctoral work leading to the Mordell–Weil theorem (1928, and shortly applied in Siegel's theorem on integral points).^{[10]}Mordell's theorem had an ad hoc proof;^{[11]} Weil began the separation of the infinite descent argument into two types of structural approach, by means of height functions for sizing rational points, and by means of Galois cohomology, which would not be categorized as such for another two decades. Both aspects of Weil's work have steadily developed into substantial theories.
Among his major accomplishments were the 1940s proof of the Riemann hypothesis for zetafunctions of curves over finite fields,^{[12]} and his subsequent laying of proper foundations for algebraic geometry to support that result (from 1942 to 1946, most intensively). The socalled Weil conjectures were hugely influential from around 1950; these statements were later proved by Bernard Dwork,^{[13]}Alexander Grothendieck,^{[14]}^{[15]}^{[16]}Michael Artin, and finally by Pierre Deligne, who completed the most difficult step in 1973.^{[17]}^{[18]}^{[19]}^{[20]}^{[21]}
Weil introduced the adele ring^{[22]} in the late 1930s, following Claude Chevalley's lead with the ideles, and gave a proof of the Riemann–Roch theorem with them (a version appeared in his Basic Number Theory in 1967).^{[23]} His 'matrix divisor' (vector bundle avant la lettre) Riemann–Roch theorem from 1938 was a very early anticipation of later ideas such as moduli spaces of bundles. The Weil conjecture on Tamagawa numbers^{[24]} proved resistant for many years. Eventually the adelic approach became basic in automorphic representation theory. He picked up another credited Weil conjecture, around 1967, which later under pressure from Serge Lang (resp. of Serre) became known as the Taniyama–Shimura conjecture (resp. Taniyama–Weil conjecture) based on a roughly formulated question of Taniyama at the 1955 Nikkō conference. His attitude towards conjectures was that one should not dignify a guess as a conjecture lightly, and in the Taniyama case, the evidence was only there after extensive computational work carried out from the late 1960s.^{[25]}
Other significant results were on Pontryagin duality and differential geometry.^{[26]} He introduced the concept of a uniform space in general topology, as a byproduct of his collaboration with Nicolas Bourbaki (of which he was a Founding Father). His work on sheaf theory hardly appears in his published papers, but correspondence with Henri Cartan in the late 1940s, and reprinted in his collected papers, proved most influential.
He discovered that the socalled Weil representation, previously introduced in quantum mechanics by Irving Segal and Shale, gave a contemporary framework for understanding the classical theory of quadratic forms.^{[27]} This was also a beginning of a substantial development by others, connecting representation theory and theta functions.
He also wrote several books on the history of Number Theory. Weil was elected Foreign Member of the Royal Society (ForMemRS) in 1966.^{[2]}
As expositor
Weil's ideas made an important contribution to the writings and seminars of Bourbaki, before and after World War II.
He says on page 114 of his autobiography that he was responsible for the null set symbol (Ø) and that it came from the Norwegian alphabet, which he alone among the Bourbaki group was familiar with.^{[28]}
Beliefs
Indian (Hindu) thought had great influence on Weil.^{[29]} In his autobiography, he says that the only religious ideas that appealed to him were those to be found in Hindu philosophical thought.^{[30]} Although he was an agnostic,^{[31]} he respected religions.^{[32]}
Books
Mathematical works:
 Arithmétique et géométrie sur les variétés algébriques (1935)
 Sur les espaces à structure uniforme et sur la topologie générale (1937)^{[33]}
 L'intégration dans les groupes topologiques et ses applications (1940)
 Weil, André (1946), Foundations of Algebraic Geometry, American Mathematical Society Colloquium Publications, vol. 29, Providence, R.I.: American Mathematical Society, ISBN 9780821810293, MR 0023093 ^{[34]}
 Sur les courbes algébriques et les variétés qui s’en déduisent (1948)
 Variétés abéliennes et courbes algébriques (1948)^{[35]}
 Introduction à l'étude des variétés kählériennes (1958)
 Discontinuous subgroups of classical groups (1958) Chicago lecture notes
 Weil, André (1967), Basic number theory., Die Grundlehren der mathematischen Wissenschaften 144, SpringerVerlag New York, Inc., New York, ISBN 3540586555, MR 0234930
 Dirichlet Series and Automorphic Forms, Lezioni Fermiane (1971) Lecture Notes in Mathematics, vol. 189,
 Essais historiques sur la théorie des nombres (1975)
 Elliptic Functions According to Eisenstein and Kronecker (1976)
 Number Theory for Beginners (1979) with Maxwell Rosenlicht
 Adeles and Algebraic Groups (1982)^{[36]}
 Number Theory: An Approach Through History From Hammurapi to Legendre (1984)^{[37]}
Collected papers:
 Œuvres Scientifiques, Collected Works, three volumes (1979)
 Weil, André (March 2009). Œuvres Scientifiques / Collected Papers (in English, French, and German). Volume 1 (19261951) (2nd printing ed.). Springer. ISBN 9783540858881.
 Weil, André (March 2009). Œuvres Scientifiques / Collected Papers (in English, French, and German). Volume 2 (19511964) (2nd printing ed.). Springer. ISBN 9783540877356.
 Weil, André (March 2009). Œuvres Scientifiques / Collected Papers (in English, French, and German). Volume 3 (19641978) (2nd printing ed.). Springer. ISBN 9783540877370.
 French: Souvenirs d’Apprentissage (1991) ISBN 3764325003. Review in English by J. E. Cremona.
 English translation: The Apprenticeship of a Mathematician (1992), ISBN 0817626506 Review by Veeravalli S. Varadarajan; Review by Saunders Mac Lane
Memoir by his daughter:
 At Home with André and Simone Weil by Sylvie Weil, translated by Benjamin Ivry; ISBN 9780810127043, Northwestern University Press, 2010.^{[38]}
References
 ^ André Weil at the Mathematics Genealogy Project
 ^ ^{a} ^{b} Serre, J.P. (1999). "Andre Weil. 6 May 1906  6 August 1998: Elected For.Mem.R.S. 1966". Biographical Memoirs of Fellows of the Royal Society 45: 519. doi:10.1098/rsbm.1999.0034.
 ^ Horgan, J (1994). "Profile: Andre Weil – The Last Universal Mathematician". Scientific American 270 (6): 33–34. doi:10.1038/scientificamerican069433.
 ^ O'Connor, John J.; Robertson, Edmund F., "André Weil", MacTutor History of Mathematics archive, University of St Andrews .
 ^ O'Connor, John J.; Robertson, Edmund F., "Weil family", MacTutor History of Mathematics archive, University of St Andrews .
 ^ Amir D. Aczel,The Artist and the Mathematician, Basic Books, 2009 pp.17ff.,p.25.
 ^ Borel, Armand
 ^ Osmo Pekonen: L'affaire Weil à Helsinki en 1939, Gazette des mathématiciens 52 (avril 1992), pp. 13—20. With an afterword by André Weil.
 ^ Weil, André. "Number theory and algebraic geometry." In Proc. Intern. Math. Congres., Cambridge, Mass., vol. 2, pp. 90–100. 1950.
 ^ A. Weil, L'arithmétique sur les courbes algébriques, Acta Math 52, (1929) p. 281315, reprinted in vol 1 of his collected papers ISBN 0387903305 .
 ^ L.J. Mordell, On the rational solutions of the indeterminate equations of the third and fourth degrees, Proc Cam. Phil. Soc. 21, (1922) p. 179
 ^ Weil, André (1949), "Numbers of solutions of equations in finite fields", Bulletin of the American Mathematical Society 55 (5): 497–508, doi:10.1090/S000299041949092194, ISSN 00029904, MR 0029393 Reprinted in Oeuvres Scientifiques/Collected Papers by André Weil ISBN 0387903305
 ^ Dwork, Bernard (1960), "On the rationality of the zeta function of an algebraic variety", American Journal of Mathematics (American Journal of Mathematics, Vol. 82, No. 3) 82 (3): 631–648, doi:10.2307/2372974, ISSN 00029327, JSTOR 2372974, MR 0140494
 ^ Grothendieck, Alexander (1960), "The cohomology theory of abstract algebraic varieties", Proc. Internat. Congress Math. (Edinburgh, 1958), Cambridge University Press, pp. 103–118, MR 0130879
 ^ Grothendieck, Alexander (1995) [1965], "Formule de Lefschetz et rationalité des fonctions L", Séminaire Bourbaki 9, Paris: Société Mathématique de France, pp. 41–55, MR 1608788
 ^ Grothendieck, Alexander (1972), Groupes de monodromie en géométrie algébrique. I, Lecture Notes in Mathematics, Vol. 288 288, Berlin, New York: SpringerVerlag, doi:10.1007/BFb0068688, ISBN 9783540059875, MR 0354656
 ^ Deligne, Pierre (1971), "Formes modulaires et représentations ladiques", Séminaire Bourbaki vol. 1968/69 Exposés 347363, Lecture Notes in Mathematics 179, Berlin, New York: SpringerVerlag, doi:10.1007/BFb0058801, ISBN 9783540053569
 ^ Deligne, Pierre (1974), "La conjecture de Weil. I", Publications Mathématiques de l'IHÉS (43): 273–307, ISSN 16181913, MR 0340258
 ^ Deligne, Pierre, ed. (1977), Séminaire de Géométrie Algébrique du Bois Marie — Cohomologie étale (SGA 4^{1}⁄_{2}), Lecture notes in mathematics (in French) 569 (569), Berlin: SpringerVerlag, doi:10.1007/BFb0091516, ISBN 9780387080666
 ^ Deligne, Pierre (1980), "La conjecture de Weil. II", Publications Mathématiques de l'IHÉS (52): 137–252, ISSN 16181913, MR 601520
 ^ Deligne, Pierre; Katz, Nicholas (1973), Groupes de monodromie en géométrie algébrique. II, Lecture Notes in Mathematics, Vol. 340 340, Berlin, New York: SpringerVerlag, doi:10.1007/BFb0060505, ISBN 9783540064336, MR 0354657
 ^ A. Weil, Adeles and algebraic groups , Birkhauser, Boston, 1982
 ^ Weil, André (1967), Basic number theory., Die Grundlehren der mathematischen Wissenschaften 144, SpringerVerlag New York, Inc., New York, ISBN 3540586555, MR 0234930
 ^ Weil, André (1959), Exp. No. 186, Adèles et groupes algébriques, Séminaire Bourbaki 5, pp. 249–257
 ^ Lang, S. "Some History of the ShimuraTaniyama Conjecture." Not. Amer. Math. Soc. 42, 13011307, 1995
 ^ Borel, A. (1999). "André Weil and Algebraic Topology" (PDF). Notices of the AMS 46 (4): 422–427.
 ^ Weil, A. (1964). "Sur certains groupes d'opérateurs unitaires". Acta Math. (in French) 111: 143–211. doi:10.1007/BF02391012.
 ^ Miller, Jeff (1 September 2010). "Earliest Uses of Symbols of Set Theory and Logic". Jeff Miller Web Pages. Retrieved 21 September 2011.
 ^ Borel, Armand. [1] (see also)[2]
 ^ Review by Veeravalli S. Varadarajan
 ^ Paul Betz; Mark Christopher Carnes, American Council of Learned Societies (2002). American National Biography: Supplement, Volume 1. Oxford University Press. p. 676. ISBN 9780195150636.
Although as a lifelong agnostic he may have been somewhat bemused by Simone Weil's preoccupations with Christian mysticism, he remained a vigilant guardian of her memory,...
 ^ I. GrattanGuinness (2004). I. GrattanGuinness, Bhuri Singh Yadav, ed. History of the Mathematical Sciences. Hindustan Book Agency. p. 63. ISBN 9788185931456.
Like in mathematics he would go directly to the teaching of the Masters. He read Vivekananda and was deeply impressed by Ramakrishna. He had affinity for Hinduism. Andre Weil was an agnostic but respected religions. He often teased me about reincarnation in which he did not believe. He told me he would like to be reincarnated as a cat. He would often impress me by readings in Buddhism.
 ^ Cairns, Stewart S. (1939). "Review: Sur les Espaces à Structure Uniforme et sur la Topologie Générale, by A. Weil" (PDF). Bull. Amer. Math. Soc. 45 (1): 59–60. doi:10.1090/s00029904193906919X.
 ^ Zariski, Oscar (1948). "Review: Foundations of Algebraic Geometry, by A. Weil" (PDF). Bull. Amer. Math. Soc. 54 (7): 671–675. doi:10.1090/s000299041948090401.
 ^ Chern, Shiingshen (1950). "Review: Variétés abéliennes et courbes algébriques, by A. Weil". Bull. Amer. Math. Soc. 56 (2): 202–204. doi:10.1090/s000299041950093914.
 ^ Humphreys, James E. (1983). "Review of Adeles and Algebraic Groups by A. Weil". Linear & Multilinear Algebra 14 (1): 111–112. doi:10.1080/03081088308817546.
 ^ Ribenboim, Paulo (1985). "Review of Number Theory: An Approach Through History From Hammurapi to Legendre, by André Weil" (PDF). Bull. Amer. Math. Soc. (N.S.) 13 (2): 173–182. doi:10.1090/s027309791985154114.
 ^ Audin, Michèle (2011). "Review: At Home with André and Simone Weil, by Sylvie Weil" (PDF). Notices of the AMS 58 (5): 697–698.
External links
Wikiquote has quotations related to: André Weil 
 André Weil, by A. Borel, Bull.AMS 46 (2009), 661666.
 André Weil: memorial articles in the Notices of AMS by Armand Borel, Pierre Cartier, Komaravolu Chandrasekharan, ShiingShen Chern, and Shokichi Iyanaga
 Image of Weil
 A 1940 Letter of André Weil on Analogy in Mathematics
 Ford Burkhart (10 August 1998). "Andre Weil, Who Reshaped Mathematics, Is Dead at 92". NY Times. Retrieved 10 January 2008.
 Paul Hoffman (3 January 1999). "The lives they lived: Andre Weil; Numbers Man". NY Times. Retrieved 23 January 2008.
 Artless innocents and ivorytower sophisticates: Some personalities on the Indian mathematical scene  M. S. Raghunathan
 Varadaraja, V.S. (April 1999). "Book Review: The Apprenticeship of a Mathematician—Autobiography of André Weil" (PDF). Notices of the AMS 46 (4): 448–456.
 La vie et l'oeuvre d'André Weil, by JP. Serre, L'Ens. Math. 45 (1999),516.
 Correspondence entre Henri Cartan et André Weil (19281991), par Michèle Audin, Doc. Math. 6, Soc. Math. France, 2011.
