Mathematicians crack 40-year-old problem on quasiregularly elliptic manifolds

A mathematical problem solved by Susanna Heikkilä relates to the classification of quasiregularly elliptic 4-manifolds, asking what four-dimensional shapes can be obtained by deforming four-dimensional Euclidean geometry. The article by Heikkilä and Pekka Pankka has been published in the Annals of Mathematics journal.