Deformations of a toric Gorenstein pair

Abstract: We consider deformations of a pair $(X,\partial X)$, where $X$ is an affine toric Gorenstein variety and $\partial X$ is its boundary. We compute the tangent and obstruction space for the corresponding deformation functor and for an admissible lattice degree $m$ we construct the miniversal deformation of $(X,\partial X)$ in degrees $-km$, for all $k\in \mathbb{N}$ together. This in particular generalizes Altmann's construction of the miniversal deformation of an isolated Gorenstein toric singularity to an arbitrary non-isolated Gorenstein toric singularity. We see that it is more natural to work with deformations of a pair $(X,\partial X)$ rather than only with deformations of $X$, since many computations are in fact easier.