Cornelia Druțu

Cornelia Druțu
Born	Iași, Romania
Alma mater	Université Paris-Sud XI University of Iași
Awards	Whitehead Prize (2009)
Scientific career
Fields	Mathematics
Institutions	University of Oxford University of Lille 1
Thesis	Réseaux non uniformes des groupes de Lie semi-simple de rang >1: invariants de quasiisométrie (1996)
Doctoral advisor	Pierre Pansu

Cornelia Druțu is a Romanian mathematician notable for her contributions in the area of geometric group theory.^[1] She is Professor of mathematics at the University of Oxford^[1] and Fellow^[2] of Exeter College, Oxford.

Education and career

Druțu was born in Iași, Romania. She attended the Emil Racoviță High School (now the National College Emil Racoviță^[3]) in Iași. She earned a B.S. in Mathematics from the University of Iași, where besides attending the core courses she received extra curricular teaching in geometry and topology from Professor Liliana Răileanu.^[2]

In 1996 Druțu earned a Ph.D. in Mathematics from University of Paris-Sud, with a thesis entitled Réseaux non uniformes des groupes de Lie semi-simple de rang supérieur et invariants de quasiisométrie, written under the supervision of Pierre Pansu.^[4] She then joined the University of Lille 1 as Maître de conférences (MCF). In 2004 she earned her Habilitation degree from the University of Lille 1.^[5]

In 2009 she became Professor of mathematics at the Mathematical Institute, University of Oxford.^[1]

She held visiting positions at the Max Planck Institute for Mathematics in Bonn, the Institut des Hautes Études Scientifiques in Bures-sur-Yvette, the Mathematical Sciences Research Institute in Berkeley, California. She visited the Isaac Newton Institute in Cambridge as holder of a Simons Fellowship.^[6] From 2013 to 2020 she chaired the European Mathematical Society/European Women in Mathematics scientific panel of women mathematicians.^[7][8]

Awards

In 2009, Druțu was awarded the Whitehead Prize by the London Mathematical Society for her work in geometric group theory.^[9]

In 2017, Druțu was awarded a Simons Visiting Fellowship.^[6]

Publications

Selected contributions

• The quasi-isometry invariance of relative hyperbolicity; a characterization of relatively hyperbolic groups using geodesic triangles, similar to the one of hyperbolic groups.
• A classification of relatively hyperbolic groups up to quasi-isometry; the fact that a group with a quasi-isometric embedding in a relatively hyperbolic metric space, with image at infinite distance from any peripheral set, must be relatively hyperbolic.
• The non-distortion of horospheres in symmetric spaces of non-compact type and in Euclidean buildings, with constants depending only on the Weyl group.
• The quadratic filling for certain linear solvable groups (with uniform constants for large classes of such groups).
• A construction of a 2-generated recursively presented group with continuum many non-homeomorphic asymptotic cones. Under the continuum hypothesis, a finitely generated group may have at most continuum many non-homeomorphic asymptotic cones, hence the result is sharp.
• A characterization of Kazhdan's property (T) and of the Haagerup property using affine isometric actions on median spaces.
• A study of generalizations of Kazhdan's property (T) for uniformly convex Banach spaces.
• A proof that random groups satisfy strengthened versions of Kazhdan's property (T) for high enough density; a proof that for random groups the conformal dimension of the boundary is connected to the maximal value of p for which the groups have fixed point properties for isometric affine actions on ${\displaystyle L^{p}}$ spaces.

Selected publications (in the order corresponding to the results above)

• Druţu, Cornelia (2009). "Relatively hyperbolic groups: geometry and quasi-isometric invariance". Commentarii Mathematici Helvetici. 84: 503–546. arXiv:math/0605211. doi:10.4171/CMH/171. MR 2507252. S2CID 7643177..
• Behrstock, Jason; Druţu, Cornelia; Mosher, Lee (2009). "Thick metric spaces, relative hyperbolicity, and quasi-isometric rigidity". Mathematische Annalen. 344 (3): 543–595. arXiv:math/0512592. doi:10.1007/s00208-008-0317-1. MR 2501302. S2CID 640737.
• Druţu, Cornelia (1997). "Nondistorsion des horosphères dans des immeubles euclidiens et dans des espaces symétriques". Geometric and Functional Analysis. 7 (4): 712–754. doi:10.1007/s000390050024. MR 1465600. S2CID 122966047.
• Druţu, Cornelia (2004). "Filling in solvable groups and in lattices in semisimple groups". Topology. 43 (5): 983–1033. arXiv:math/0110107. doi:10.1016/j.top.2003.11.004. MR 2079992. S2CID 15240355.
• Druţu, Cornelia; Sapir, Mark (2005). "Tree-graded spaces and asymptotic cones of groups". Topology. 44 (5). With an appendix by Denis Osin and Mark Sapir: 959–1058. arXiv:math/0405030. doi:10.1016/j.top.2005.03.003. MR 2153979. S2CID 119658274.
• Chatterji, Indira; Druţu, Cornelia; Haglund, Frédéric (2010). "Kazhdan and Haagerup properties from the median viewpoint". Advances in Mathematics. 225 (2): 882–921. CiteSeerX 10.1.1.313.1428. doi:10.1016/j.aim.2010.03.012. MR 2671183.
• Druțu, Cornelia; Nowak, Piotr W. (2017). "Kazhdan projections, random walks and ergodic theorems". Journal für die reine und angewandte Mathematik. 2019 (754): 49–86. arXiv:1501.03473. doi:10.1515/crelle-2017-0002. S2CID 118775530.
• Druțu, Cornelia; Mackay, John (2019). "Random groups, random graphs and eigenvalues of p-Laplacians". Advances in Mathematics. 341: 188–254. arXiv:1607.04130. doi:10.1016/j.aim.2018.10.035. MR 3872847.

Published book

• Druțu, Cornelia; Kapovich, Michael (2018). Geometric Group Theory (PDF). American Mathematical Society Colloquium Publications. Vol. 63. Providence, RI: American Mathematical Society. ISBN 978-1-4704-1104-6. MR 3753580.

See also

• Geometric group theory
• Ultralimit
• Tree-graded space
• Kazhdan's property (T)

References

External links

• personal webpage, University of Oxford
• "MathSciNet". Retrieved October 31, 2010.
• "ArXiv.org". Retrieved October 31, 2010.
• Cornelia Druţu. "Papers". Retrieved October 31, 2010.