Étienne Blanchard was a Research Fellow at IMJ-PRG, in the Operator Algebras team.
He was born in 1968 in Cambrai (North of France). After his preparatory classes at Lycée Louis-le-Grand (Paris), he joined Ecole Normale Supérieure (Ulm) in 1988. He defended his thesis at the University Paris 7 in November 1993 under the direction of Georges Skandalis and was immediately recruited by the CNRS. After two years in Heidelberg, he moved to Marseille - at the Institut de mathématiques de Luminy where he defended his Habilitation à Diriger des Recherches in June 2000. He joined the IMJ-PRG and its Operator Algebras team in 2001. He led the team from 2004 to 2012.
Étienne’s mathematical work was mainly focused on fields of operator algebras. In the years following his thesis, he studied Hopf C*-algebras and several quantum deformations of groups, seen as fields of algebras over a deformation parameter.
His work led him to explore various questions about fields of C*-algebras. He published several papers alone, and also in collaboration with many mathematicians: K. Dykema, E. Kirchberg, M. Rørdam, S. Wassermann... Among other things, he studied the tensor product of such fields; he tackled the problem of classifying fields of simple C*-algebras, and established a natural and nice generalization of the classification of simple C*-algebras; he made an important series of contributions on questions of the following type: given a field of C*-algebras whose fiber has a property, what can be said on the field itself. In particular, he studied the case where the fiber is exact, or isomorphic to the algebra O infinity of Cuntz…
From 2010 to 2013, he directed the thesis of Amaury Freslon.
Very soon after his thesis, Etienne had to face the first attacks of multiple sclerosis. He has been impressive in his fight against the disease, showing an incredible fighting spirit and good mood, and nevertheless managed to produce a scientific work of a very high level. Many of his colleagues, in France and abroad, will long remember his simplicity, his humor, his enthusiasm, his courage and his energy, always positive.