Simultaneous minimal model of homogeneous toric deformation

Abstract

For a flat family of Du Val singularities, we can take a simultaneous resolution after finite base change. It is an interesting problem to consider this analogy for a flat family of higher dimensional canonical singularities. In this note, we consider an existence of simultaneous terminalization for K. Altmann's homogeneous toric deformation whose central fibre is an affine Gorenstein toric singularity. We obtain examples that there are no simultaneous terminalization even after finite base change and give a sufficient condition for an existence of simultaneous terminalization. Some examples of 4-dimensional flop are obtained as an application.