Seminar series
          
      Date
              Thu, 22 Feb 2018
      
16:00
          16:00
Location
              C5
          Speaker
              Matthias Wink
          Organisation
              Oxford University
          A theorem of Gromov states that the number of generators of the fundamental group of a manifold with nonnegative 
	curvature is bounded by a constant which only depends on the dimension of the manifold. The main ingredient 
	in the proof is Toponogov’s theorem, which roughly speaking says that the triangles on spaces with positive 
	curvature, such as spheres, are thick compared to triangles in the Euclidean plane. In the talk I shall explain 
	this more carefully and deduce Gromov’s result.