The Universal Deformation of the Witt Ring Scheme
arXiv:1604.03319 · doi:10.1070/SM8730
Abstract
We determine the universal deformation over reduced base rings of the Witt ring scheme enhanced by a Frobenius lift and Verschiebung. It agrees with a q-deformation earlier introduced by the second author, for which we also give a simpler description. In the appendix we discuss a Witt vector theory for ind-rings which may be of independent interest.