Department of Mathematics


  •  How to define the Torelli group of a surface with boundary?
  •  10/24/2016
  •  4:10 PM - 5:00 PM
  •  C304 Wells Hall
  •  Nikolai Ivanov, MSU

The Torelli group of a closed surface S is defined as the group of diffeomorphisms of S acting trivially on homology and considered up to isotopy. These groups naturally arise in topology of 3-manifolds and in algebraic geometry. At the same time they are quite interesting groups by themselves. In order to study them, it is highly desirable to have also Torelli groups of surfaces with non-empty boundary. It turns out that the naive definition is not a good one.



Department of Mathematics
Michigan State University
619 Red Cedar Road
C212 Wells Hall
East Lansing, MI 48824

Phone: (517) 353-0844
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College of Natural Science