Gilles Carron (Université de Nantes) will speak in the geometry seminar on Tuesday 4 December, at 1.30pm in the Salle de Profs. Gilles’s title is *A Bonnet-Myers theorem under a spectral condition* and his abstract is below.

This is joint work with C. Rose (TU Chemnitz, Germany). According to the Bonnet-Myers theorem, a complete Riemmannian manifold with Ricci curvature bounded from below by a positive constant is closed and has finite fundamental group. We obtain that a closed Riemannian manifold for which a certain Schrodinger operator is positive has finite fundamental group.