Laurent polynomials and deformations of non-isolated Gorenstein toric sigularities

Abstract: We establish a correspondence between one-parameter deformations of an affine Gorenstein toric pair $(X_P,\partial X_P)$, defined by a polytope $P$, and mutations of a Laurent polynomial $f$ whose Newton polytope $\Delta(f)$ is equal to $P$. For a Laurent polynomial $f$ in two variables, we construct a formal deformation of a three-dimensional Gorenstein toric pair $(X_{\Delta(f)},\partial X_{\Delta(f)})$ over $\mathbb{C}[[t_f]]$, where $t_f$ is the set of deformation parameters coming from mutations. Moreover, we show that the general fiber of this deformation is smooth if and only if $f$ is $0$-mutable. Our construction provides a potential approach for classifying Fano manifolds with a very ample anticanonical bundle.