Cornelia Druțu

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

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

She held visiting positions at the

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-
  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".
  S2CID 7643177
  ..
• S2CID 640737
  .
• Druţu, Cornelia (1997). "Nondistorsion des horosphères dans des immeubles euclidiens et dans des espaces symétriques".
  S2CID 122966047
  .
• Druţu, Cornelia (2004). "Filling in solvable groups and in lattices in semisimple groups".
  S2CID 15240355
  .
• Druţu, Cornelia;
  S2CID 119658274
  .
• MR 2671183
  .
• Druțu, Cornelia; Nowak, Piotr W. (2017). "Kazhdan projections, random walks and ergodic theorems".
  S2CID 118775530
  .
• Druțu, Cornelia; Mackay, John (2019). "Random groups, random graphs and eigenvalues of p-Laplacians".
  MR 3872847
  .