A counter-example to the equivariance structure on semi-universal deformation

An Khuong Doan

doi:10.1007/s12220-020-00411-4

paper

A counter-example to the equivariance structure on semi-universal deformation

arXiv:1906.00082 · doi:10.1007/s12220-020-00411-4

Abstract

If $X$ is a projective variety and $G$ is an algebraic group acting algebraically on $X$ , we provide a counter-example to the existence of a $G$ -equivariant extension on the formal semi-universal deformation of $X$ .

13 pages, Remark 1.1, Definition 1.6, Definition 1.7, and Remark 4.1 have been added. A slight change in the proof of Theorem 4.1. To appear in The Journal of Geometric analysis