Geometric Models for Algebraic Suspensions

Abstract

Abstract We analyze the question of which motivic homotopy types admit smooth schemes as representatives. We show that given a pointed smooth affine scheme $X$ and an embedding into affine space, the affine deformation space of the embedding gives a model for the ${\mathbb P}^{1}$ suspension of $X$; we also analyze a host of variations on this observation. Our approach yields many examples of ${\mathbb A}^{1}$-$(n-1)$-connected smooth affine $2n$-folds and strictly quasi-affine ${\mathbb A}^{1}$-contractible smooth schemes.