Lê Dũng Tráng, (born 1947 in

Saigon , population_density_km2 = 4,292 , population_density_metro_km2 = 697.2 , population_demonym = Saigonese , blank_name = GRP (Nominal) , blank_info = 2019 , blank1_name = – Total , blank1_ ...

) is a

Vietnamese Vietnamese may refer to: * Something of, from, or related to Vietnam, a country in Southeast Asia ** A citizen of Vietnam. See Demographics of Vietnam. * Vietnamese people, or Kinh people, a Southeast Asian ethnic group native to Vietnam ** Overse ...

French French (french: français(e), link=no) may refer to: * Something of, from, or related to France ** French language, which originated in France, and its various dialects and accents ** French people, a nation and ethnic group identified with Franc ...

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History On ...

Life and work

In the 1950s, Lê Dũng Tráng came to

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...

, where he attended the

Lycée Louis-le-Grand The Lycée Louis-le-Grand (), also referred to simply as Louis-le-Grand or by its acronym LLG, is a public Lycée (French secondary school, also known as sixth form college) located on rue Saint-Jacques in central Paris. It was founded in the ...

Paris Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. S ...

. He obtained a

Ph.D. degree A Doctor of Philosophy (PhD, Ph.D., or DPhil; Latin: or ') is the most common degree at the highest academic level awarded following a course of study. PhDs are awarded for programs across the whole breadth of academic fields. Because it is ...

at the

University of Paris , image_name = Coat of arms of the University of Paris.svg , image_size = 150px , caption = Coat of Arms , latin_name = Universitas magistrorum et scholarium Parisiensis , motto = ''Hic et ubique terrarum'' (Latin) , mottoeng = Here and a ...

in 1969 and 1971 under the supervision of

Claude Chevalley Claude Chevalley (; 11 February 1909 – 28 June 1984) was a French mathematician who made important contributions to number theory, algebraic geometry, class field theory, finite group theory and the theory of algebraic groups. He was a foundin ...

and

Pierre Deligne Pierre René, Viscount Deligne (; born 3 October 1944) is a Belgian mathematician. He is best known for work on the Weil conjectures, leading to a complete proof in 1973. He is the winner of the 2013 Abel Prize, 2008 Wolf Prize, 1988 Crafoord Pr ...

. From 1975 to 1999, he was professor at the

University of Paris VII A university () is an institution of higher (or tertiary) education and research which awards academic degrees in several academic disciplines. Universities typically offer both undergraduate and postgraduate programs. In the United States, t ...

and research director of the

CNRS The French National Centre for Scientific Research (french: link=no, Centre national de la recherche scientifique, CNRS) is the French state research organisation and is the largest fundamental science agency in Europe. In 2016, it employed 31,637 ...

. From 1983 to 1995 he was also a professor at the

École Polytechnique École may refer to: * an elementary school in the French educational stages normally followed by secondary education establishments (collège and lycée) * École (river), a tributary of the Seine flowing in région Île-de-France * École, Savoi ...

. From 2002 to 2009 he headed the department of mathematics at the

International Centre for Theoretical Physics The Abdus Salam International Centre for Theoretical Physics (ICTP) is an international research institute for physical and mathematical sciences that operates under a tripartite agreement between the Italian Government, United Nations Education ...

(ICTP), in

Trieste Trieste ( , ; sl, Trst ; german: Triest ) is a city and seaport in northeastern Italy. It is the capital city, and largest city, of the autonomous region of Friuli Venezia Giulia, one of two autonomous regions which are not subdivided into provi ...

, Italy. He was a frequent guest scientist at

Harvard University Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher le ...

(with

Phillip Griffiths Phillip Augustus Griffiths IV (born October 18, 1938) is an American mathematician, known for his work in the field of geometry, and in particular for the complex manifold approach to algebraic geometry. He was a major developer in particul ...

) and

Northeastern University Northeastern University (NU) is a private university, private research university with its main campus in Boston. Established in 1898, the university offers undergraduate and graduate programs on its main campus as well as satellite campuses in ...

(with

Terence Gaffney Terence Gaffney (born 9 March 1948) is an American mathematician who has made fundamental contributions to singularity theory – in particular, to the fields of singularities of maps and equisingularity theory. Professional career He is a Profes ...

and David B. Massey). He is particularly concerned with singularity theory in the complex domain ( Milnor fibrations,

perverse sheaves The mathematical term perverse sheaves refers to a certain abelian category associated to a topological space ''X'', which may be a real or complex manifold, or a more general topologically stratified space, usually singular. This concept was intro ...

). In 2000 he was involved in promoting scientific exchange between the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

and

Vietnam Vietnam or Viet Nam ( vi, Việt Nam, ), officially the Socialist Republic of Vietnam,., group="n" is a country in Southeast Asia, at the eastern edge of mainland Southeast Asia, with an area of and population of 96 million, making i ...

. For this, he received an honorary doctorate from the

Vietnam Academy of Science and Technology The Vietnam Academy of Science and Technology ( vi, Viện Hàn lâm Khoa học và Công nghệ Việt Nam) is the largest and most prominent research institute in Vietnam. It was founded on 20 May 1975 as the Vietnam Academy of Science, and ren ...

in 2004.ICTP release 2004
/ref> He is a Fellow of the

Third World Academy of Sciences The World Academy of Sciences (TWAS) is a merit-based science academy established for developing countries, uniting 1,000 scientists in some 70 countries. Its principal aim is to promote scientific capacity and excellence for sustainable devel ...

. His students include

Hélène Esnault Hélène Esnault (born 17 July 1953) is a French and German mathematician, specializing in algebraic geometry. Biography Born in Paris, Esnault earned her PhD in 1976 from the University of Paris VII. She wrote her dissertation on ''Singularit ...

and Claude Sabbah.

Selected publications

* Introduction à la théorie des singularités, Paris, Hermann, 2 volumes, 1988. * Publisher: Algebraic approach to differential equations, Bibliotheca Alexandrina, Alexandria, Nov. 2007, World Scientific 2010. * Editor with

Kyoji Saito Kyōji Saitō (齋藤恭司, Saitō Kyōji; born 25 December 1944) is a Japanese mathematician, specializing in algebraic geometry and complex analytic geometry. Education and career Saito received in 1971 his promotion Ph.D. from the Universi ...

and

Bernard Teissier Bernard Teissier (; born 1945) is a French mathematician and a member of the Nicolas Bourbaki group. He has made major contributions to algebraic geometry and commutative algebra, specifically to singularity theory, multiplicity theory and va ...

: Singularity Theory,

World Scientific World Scientific Publishing is an academic publisher of scientific, technical, and medical books and journals headquartered in Singapore. The company was founded in 1981. It publishes about 600 books annually, along with 135 journals in various f ...

1995. *''Topology of hypersurfaces complexes'', in singularités à Cargese, astérisque 7/8, 1973, 171–182. * with

C. P. Ramanujam Chakravarthi Padmanabhan Ramanujam (9 January 1938 – 27 October 1974) was an Indian mathematician who worked in the fields of number theory and algebraic geometry. He was elected a fellow of the Indian Academy of Sciences in 1973. Like his ...

, ''The invariance of Milnor's number implies the invariance of the topological type'',

American Journal of Mathematics The ''American Journal of Mathematics'' is a bimonthly mathematics journal published by the Johns Hopkins University Press. History The ''American Journal of Mathematics'' is the oldest continuously published mathematical journal in the United ...

98 (1976), 67–78 *''Calcul du nombre de cycles évanouissants d'une hyper surface complexe'',

Annales de l'Institut Fourier The ''Annales de l'Institut Fourier'' is a French mathematical journal publishing papers in all fields of mathematics. It was established in 1949. The journal publishes one volume per year, consisting of six issues. The current editor-in-chief is ...

23 (1973), 261–270
NUMDAM
*''Topological Use of Polar Curves'', Proc. Symp Pure Math, Volume 29, 1975, pp 507–512. * with Francoise Michel and Claude Weber, ''Courbes polaires et topologie des courbes planes'',

Annales Scientifiques de l'École Normale Supérieure ''Annales Scientifiques de l'École Normale Supérieure'' is a French scientific journal of mathematics published by the Société Mathématique de France. It was established in 1864 by the French chemist Louis Pasteur and published articles in ma ...

, Sér.4, band 24, 1991, pp. 141–169
NUMDAM
* ''The geometry of the monodromy theorem'' in ''C. P. Ramanujam – a tribute'', Tata Institute, Springer Verlag 1978, 157–173 * with Helmut Hamm, ''Un théoreme de Zariski du type de Lefschetz'',

6 (1973), 317–366.

Literature

* Jean-Paul Brasselet, José Luis Cisneros-Molina, David Massey, José Seade,

(Editor) ''Singularities : international conference in honor of the 60th birthday of Lê Dũng Tráng'', Cuernavaca/Mexico 2007, 2 volumes, Contemporary Mathematics, American Mathematical Society 2008.

References

External links

Portrait at Northeastern University

David Massey, Lê's work on hypersurface singularities
{{DEFAULTSORT:Le, Dung Trang French people of Vietnamese descent 20th-century Vietnamese mathematicians Topologists 20th-century French mathematicians 21st-century French mathematicians Lycée Louis-le-Grand alumni University of Paris alumni Academic staff of Paris Diderot University Research directors of the French National Centre for Scientific Research