# Galois Deformation Rings and Base Change to a Quadratic Field

## Arithmétique

Lieu:
Salle Kampé de Fériet
Orateur:
Haruzo Hida
Affiliation:
UCLA
Dates:
Mercredi, 14 Novembre, 2018 - 10:45 - 11:45
Résumé:
Fix a prime p>3 and consider the universal 2-dimensional minimal p-ordinary deformation with coefficients in the universal ring T, of a modulo  p  induced representation r from a quadratic field F. The twist by the quadratic character of  F  induces an involution i on T.  We describe the fixed subring T_+   as the universal minimal pseudo-character ring deforming the restriction of Tr(r) to the Galois group over  F.