A short introduction to shadows of 4-manifolds
arXiv:math/0405582
Abstract
We give a self-contained introduction to the theory of Turaev's shadows as a tool to study 3 and 4-manifolds. The goal of the present paper twofold: on one side it is intended to be a shortcut to a basic use of the theory of shadows, on the other side it gives a sketchy overview of some of the recent results on shadows. No original result is proved here and most of the details of the proofs are not included.
19 pages, 8 figures. Revised version, to appear in Fundamenta Mathematicae