Author： Bleher Frauke
Publisher： Springer Publishing Company
ISSN： 0025-5831
Source： Mathematische Annalen, Vol.337, Iss.4, 2007-04, pp. : 739-767
Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.
Abstract
We answer a question of M. Flach by showing that there is a linear representation of a profinite group whose (unrestricted) universal deformation ring is not a complete intersection. We show that such examples arise in arithmetic in the following way. There are infinitely many real quadratic fields F for which there is a mod 2 representation of the Galois group of the maximal unramified extension of F whose universal deformation ring is not a complete intersection. Finally, we discuss bounds on the singularities of universal deformation rings of representations of finite groups in terms of the nilpotency of the associated defect groups.
Related content
Access to resources
Recommend
q -deformation of Witt-Burnside rings
By Oh Young-Tak
Mathematische Zeitschrift, Vol. 257, Iss. 1, 2007-09 ,pp. :
New gas and dry vessel sealing system eliminates need for O-rings
World Pumps, Vol. 2001, Iss. 419, 2001-08 ,pp. :