A note on codimension $2$ spun embedding
Sneha Banerjee, Shital Lawande, Subhadeep Rana, Kuldeep Saha
TL;DR
The paper proves that if a binding component $B$ of an open book on $M$ carries an open book, then every open book on $B$ spun embeds in $M$, via a generalized page-trick built on Seifert-type embeddings and ambient isotopies realizing monodromies. This yields far-reaching codimension-2 spun embeddings, including that any open book on a simply connected spin $5$-manifold spun embeds in $S^7$ and any $3$-dimensional open book spun embeds in $S^5$, and it introduces Morse open books and a Morse version of the page trick. The method hinges on a generalization of the Hopf annulus trick to a broad “page trick” framework, enabling monodromy powers to be realized as ambient diffeomorphisms and enabling concatenations that produce branched-cover total spaces. The results connect to Brieskorn manifolds and generalized plumbing, and extend to Morse open books, widening the scope of feasible spun embeddings in high-dimensional spheres with potential implications for contact-topological embeddings and universal open-book questions.
Abstract
We prove that if a closed manifold $B$ is a connected component of the binding of an open book decomposition of a manifold $M$, then every open book decomposition of $B$ spun embeds in $M$. As an application, we prove that every open book decomposition of a simply connected spin $5$-manifold spun embeds in $S^7$ and every $3$-dimensional open book spun embeds in $S^5$. We also define a notion of spun embedding for Morse open books.
