Displaying similar documents to “4-Manifolds which embed in IR6 but not in IR5, and Seifert manifolds for fibered knots.”

On manifold spines and cyclic presentations of groups

Alberto Cavicchioli, Friedrich Hegenbarth, Dušan Repovš (1998)

Banach Center Publications


This is a survey of results and open problems on compact 3-manifolds which admit spines corresponding to cyclic presentations of groups. We also discuss questions concerning spines of knot manifolds and regular neighborhoods of homotopically PL embedded compacta in 3-manifolds.

A short introduction to shadows of 4-manifolds

Francesco Costantino (2005)

Fundamenta Mathematicae


We give a self-contained introduction to the theory of shadows as a tool to study smooth 3-manifolds and 4-manifolds. The goal of the present paper is twofold: on the one hand, it is intended to be a shortcut to a basic use of the theory of shadows, on the other hand it gives a sketchy overview of some of the most recent results on shadows. No original result is proved here and most of the details of the proofs are left out.