2004/06/30 by Frank Calegari, Calegari, Frank
Mathematics · #Advanced Topics in Algebra #Algebraic Geometry and Number Theory #Finite Group Theory Research #math.NT #msc:11F80
paper · pdf · doi:10.48550/arxiv.math/0407003
final version
arxiv created 2005/03/17 · arxiv updated 2009/12/01
We prove R = T theorems for certain reducible residual Galois representations. We answer in the positive a question of Gross and Lubin on whether certain Hecke algebras T are discrete valuation rings. In order to prove these results we determine (using the theory of Breuil modules) when two finite flat group schemes G and H of order p over an arbitrarily tamely ramified discrete valuation ring admit an extension not killed by p.