Affiliation:
1. Laboratoire de mathematiques, Université Paris-Sud XI, CEDEX, 91405 Orsay, France
Abstract
In this short note, I present a very quick review of the peculiarities of dimension four in geometric topology. I consider, in particular, the role of geometric simple connectivity (which means handle decomposition without handles of index one) for both closed manifolds and open manifolds and for finitely presented groups, together with some of recent developments in geometric group theory.
Subject
General Mathematics,Engineering (miscellaneous),Computer Science (miscellaneous)