Twist maps and codimension-1 spun embeddings

Abstract

We study codimension $1$ embeddings preserving open book structures. In particular, we prove that every closed orientable 3-manifold admits a codimension-1 spun embedding in a finite connected sum of $S^2\times S^2$s and $S^2\tilde{\times }{S}^2$s. We discuss some explicit constructions of planar open books on 3-manifolds and their codimension $1$ spun embeddings. To construct these embeddings, we use sphere twist maps and push maps. We also give a simple proof for nontriviality of the twist map along a nonseparating $S^n$ in the group of orientation preserving diffeomorphisms of $S^1\times S^n\setminus D^{n+1}$, relative to the boundary.