Department of

January 2019 February 2019 March 2019 Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa 1 2 3 4 5 1 2 1 2 6 7 8 9 10 11 12 3 4 5 6 7 8 9 3 4 5 6 7 8 9 13 14 15 16 17 18 19 10 11 12 13 14 15 16 10 11 12 13 14 15 16 20 21 22 23 24 25 26 17 18 19 20 21 22 23 17 18 19 20 21 22 23 27 28 29 30 31 24 25 26 27 28 24 25 26 27 28 29 30 31

Monday, February 11, 2019

**Abstract:** I will discuss a result stating that a compact, Hausdorff, Lie groupoid is rigid. i.e., has no non-trivial deformations. As an application of this result, it follows that a compact, Hausdorff foliation is rigid if and only if the generic leaf has trivial 1st cohomology. This is closely related to old stability results for foliations due to Epstein, Rosenberg and Hamilton. This talk is based on joint work with Matias del Hoyo.