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Galois Seminar

Friday, November 4, 2005 - 3:15pm

Frauke Bleher

Univ. of Pennsylvania and Univ. of Iowa

Location

University of Pennsylvania

DRL 4N30

Sequel to previous week's talk.

This is the second of two talks with T. Chinburg about deformation rings which are not complete intersections. I will first discuss the connection between capping groups and deformation rings. I will then prove that every 2-dimensional irreducible representation of S_4 over a field of characteristic 2 has a universal deformation ring which is not a complete intersection. Combining this with the results from the previous week, we then get infinitely many arithmetic examples.