A building block of homotopy theory is the fundamental group of varieties, in topology and in arithmetic geometry. We know very little on it. One way to approach it is via local systems, that is linear representations modulo conjugation. In doing so we lose a lot of information. Still arithmetic geometry  (notably the Langlands program) yields obstructions for a finitely presented group to be the fundamental group of a smooth complex quasi-projective variety.
 
Based on joint work with Johan de Jong and Michael Groechenig




This special ICTP Math Colloquium will be given by Prof. Hélène Esnault. The talk on "Complex quasi-projective varieties and their fundamental groups" will take place in the Luigi Stasi Lecture Room, on Tuesday 10 December at 14.00 hrs and will be followed by light refreshments. All are welcome to attend.

Please register in advance for this meeting:
https://zoom.us/meeting/register/tJEudOqurTwjG9wy2qT4Nc66oG8lnuPgmYcq
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Hélène Esnault is a mathematician specializing in algebraic and arithmetic geometry. She obtained her PhD in 1976 at the University of Paris VII under the direction of Lê Dũng Tráng. She was a Heisenberg scholar at the MPI in Bonn and maître de conférence in Paris VII. In 1990, she became a full professor at the Universität Duisburg-Essen. In 2012, she moved to Berlin as the first Einstein Professor at the Freie Universität Berlin, where she became emerita in 2019. She continued her mathematical work and accepted a visiting professor position in 2019 at IAS Princeton. In the fall 2022, she held the Eilenberg Chair at Columbia University and is currently a part-time professor at Copenhagen University and a Faculty Associate at Harvard University.
 
As a mathematician, she published more than 135 research articles with 45 coauthors covering a wide range of topics. In recognition of her seminal contributions, she was awarded the Doisteau-Blutet prize of the Academy of Sciences in Paris in 2001, jointly with Eckart Viehweg  the Leibniz Prize in 2003 and received the Cantor medal of the German Mathematical Society in 2019. She received multiple honorary doctorates and was a member of various significant committees, including the Fields Medal Committee, the Structure Committee, the Shaw Prize Committee, and the Infosys Prize Committee. Additionally, she has served on the editorial boards of several prestigious journals.