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Non-arithmetic lattices

Presented by: 
John Parker University of Durham
Tuesday 25th April 2017 -
11:00 to 12:00
INI Seminar Room 2
In 1980 Mostow found the first examples of non-arithmetic lattices in PU(2,1). More examples were found and Deligne and Mostow gave a list of examples in 1986. Work of McMullen, based on work of Kappes and Moeller, showed there are 9 commensurability classes of non-arithmeticlattices in PU(2,1) on this list. No new examples were found until my recent work with Deraux and Paupert. We have constructed 13 new commensurability classes. I will give a history of this problem and then outline our recent results.

University of Cambridge Research Councils UK
    Clay Mathematics Institute London Mathematical Society NM Rothschild and Sons