Uwe Jannsen (born 11 March 1954) is a German mathematician, specializing in

algebra Algebra is a branch of mathematics that deals with abstract systems, known as algebraic structures, and the manipulation of expressions within those systems. It is a generalization of arithmetic that introduces variables and algebraic ope ...

algebraic number theory Algebraic number theory is a branch of number theory that uses the techniques of abstract algebra to study the integers, rational numbers, and their generalizations. Number-theoretic questions are expressed in terms of properties of algebraic ob ...

, and

algebraic geometry Algebraic geometry is a branch of mathematics which uses abstract algebraic techniques, mainly from commutative algebra, to solve geometry, geometrical problems. Classically, it studies zero of a function, zeros of multivariate polynomials; th ...

Education and career

Born in

Meddewade Meddewade is a municipality in the district of Stormarn, in Schleswig-Holstein, Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and ...

, Jannsen studied mathematics and physics at the

University of Hamburg The University of Hamburg (, also referred to as UHH) is a public university, public research university in Hamburg, Germany. It was founded on 28 March 1919 by combining the previous General Lecture System ('':de:Allgemeines Vorlesungswesen, ...

with

Diplom A ''Diplom'' (, from ) is an academic degree in the German-speaking countries Germany, Austria, and Switzerland and a similarly named degree in some other European countries including Albania, Bulgaria, Belarus, Bosnia and Herzegovina, Croatia ...

in mathematics in 1978 and with

Promotion Promotion may refer to: Marketing * Promotion (marketing), one of the four marketing mix elements, comprising any type of marketing communication used to inform or persuade target audiences of the relative merits of a product, service, brand or i ...

(PhD) in 1980 under Helmut Brückner and

Jürgen Neukirch Jürgen Neukirch (24 July 1937 – 5 February 1997) was a German mathematician known for his work on algebraic number theory. Education and career Neukirch received his diploma in mathematics in 1964 from the University of Bonn. For his Ph.D. t ...

with thesis ''Über Galoisgruppen lokaler Körper'' (On Galois groups of local fields). In the academic year 1983–1984 he was a postdoc at

Harvard University Harvard University is a Private university, private Ivy League research university in Cambridge, Massachusetts, United States. Founded in 1636 and named for its first benefactor, the History of the Puritans in North America, Puritan clergyma ...

. From 1980 to 1989 he was an assistant and then

docent The term "docent" is derived from the Latin word , which is the third-person plural present active indicative of ('to teach, to lecture'). Becoming a docent is often referred to as habilitation or doctor of science and is an academic qualifi ...

at the

University of Regensburg The University of Regensburg () is a public research university located in the city of Regensburg, Germany. The university was founded on 18 July 1962 by the Landtag of Bavaria as the fourth full-fledged university in Bavaria. Following groundbr ...

, where he received in 1988 his

habilitation Habilitation is the highest university degree, or the procedure by which it is achieved, in Germany, France, Italy, Poland and some other European and non-English-speaking countries. The candidate fulfills a university's set criteria of excelle ...

. From 1989 to 1991 he held a research professorship at the

Max-Planck-Institut für Mathematik The Max Planck Institute for Mathematics (, MPIM) is a research institute located in Bonn, Germany. It is named in honor of the German physicist Max Planck and forms part of the Max Planck Society (''Max-Planck-Gesellschaft''), an association of ...

Bonn Bonn () is a federal city in the German state of North Rhine-Westphalia, located on the banks of the Rhine. With a population exceeding 300,000, it lies about south-southeast of Cologne, in the southernmost part of the Rhine-Ruhr region. This ...

. In 1991 he became a full professor at the

University of Cologne The University of Cologne () is a university in Cologne, Germany. It was established in 1388. It closed in 1798 before being re-established in 1919. It is now one of the largest universities in Germany with around 45,187 students. The Universit ...

and since 1999 he has been a professor at the University of Regensburg. Jannsen's research deals with, among other topics, the

Galois theory In mathematics, Galois theory, originally introduced by Évariste Galois, provides a connection between field (mathematics), field theory and group theory. This connection, the fundamental theorem of Galois theory, allows reducing certain problems ...

algebraic number field In mathematics, an algebraic number field (or simply number field) is an extension field K of the field of rational numbers such that the field extension K / \mathbb has finite degree (and hence is an algebraic field extension). Thus K is a ...

s, the theory of motives in algebraic geometry, the Hasse principle (local–global principle), and resolution of singularities. In particular, he has done research on a

cohomology theory In mathematics, specifically in homology theory and algebraic topology, cohomology is a general term for a sequence of abelian groups, usually one associated with a topological space, often defined from a cochain complex. Cohomology can be viewed ...

for

algebraic varieties Algebraic varieties are the central objects of study in algebraic geometry, a sub-field of mathematics. Classically, an algebraic variety is defined as the set of solutions of a system of polynomial equations over the real or complex numbers. ...

, involving their extension in mixed motives as a development of research by

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 Crafoor ...

, and a

motivic cohomology Motivic cohomology is an invariant of algebraic varieties and of more general schemes. It is a type of cohomology related to motives and includes the Chow ring of algebraic cycles as a special case. Some of the deepest problems in algebraic geome ...

as a development of research by

Vladimir Voevodsky Vladimir Alexandrovich Voevodsky (, ; 4 June 1966 – 30 September 2017) was a Russian-American mathematician. His work in developing a homotopy theory for algebraic varieties and formulating motivic cohomology led to the award of a Fields Medal ...

. In the 1980s with Kay Wingberg he completely described the absolute Galois group of ''p''-adic number fields, ''i.e.'' in the local case. In 1994 he was an Invited Speaker with talk ''Mixed motives, motivic cohomology and Ext-groups'' at the

International Congress of Mathematicians The International Congress of Mathematicians (ICM) is the largest conference for the topic of mathematics. It meets once every four years, hosted by the International Mathematical Union (IMU). The Fields Medals, the IMU Abacus Medal (known before ...

Zürich Zurich (; ) is the list of cities in Switzerland, largest city in Switzerland and the capital of the canton of Zurich. It is in north-central Switzerland, at the northwestern tip of Lake Zurich. , the municipality had 448,664 inhabitants. The ...

. He was elected in 2009 a full member of the

Bayerische Akademie der Wissenschaften The Bavarian Academy of Sciences and Humanities () is an independent public institution, located in Munich. It appoints scholars whose research has contributed considerably to the increase of knowledge within their subject. The general goal of th ...

and in 2011 a full member of the

Academia Europaea The Academia Europaea is a pan-European Academy of humanities, letters, law, and sciences. The Academia was founded in 1988 as a functioning Europe-wide Academy that encompasses all fields of scholarly inquiry. It acts as co-ordinator of Europe ...

. His doctoral students include Moritz Kerz.

Selected publications

* Continuous étale cohomology, Mathematische Annalen vol. 280, no. 2 1988, pp. 207–245
"On the ℓ-adic cohomology of varieties over number fields and its Galois cohomology."
In ''Galois Groups over

\mathbb

'', pp. 315–360. Springer, New York, NY, 1989.
Mixed motives and algebraic K-theory
Lecture Notes in Mathematics vol. 1400, Springer Verlag 1990 (with appendices by C. Schoen and

Spencer Bloch Spencer Janney Bloch (born May 22, 1944; New York City) is an American mathematician known for his contributions to algebraic geometry and algebraic ''K''-theory. Bloch is a R. M. Hutchins Distinguished Service Professor Emeritus in the Departm ...

). * with

Steven Kleiman Steven Lawrence Kleiman (born March 31, 1942) is an American mathematician. Professional career Kleiman is a professor emeritus of mathematics at the Massachusetts Institute of Technology. Born in Boston, he did his undergraduate studies at MIT ...

and

Jean-Pierre Serre Jean-Pierre Serre (; born 15 September 1926) is a French mathematician who has made contributions to algebraic topology, algebraic geometry and algebraic number theory. He was awarded the Fields Medal in 1954, the Wolf Prize in 2000 and the inau ...

(eds.): Motives, Proc. Symposium Pure Mathematics vol. 55, 2 vols., American Mathematical Society 1994 (Conference University of Washington, Seattle, 1991
vol. 2
* Motives, numerical equivalence and semi-simplicity, Inventiones Mathematicae, vol. 107 1992, pp. 447–452

References

External links

{{DEFAULTSORT:Jannsen, Uwe 20th-century German mathematicians 21st-century German mathematicians University of Hamburg alumni Academic staff of the University of Regensburg Academic staff of the University of Cologne 1954 births Living people