**Memoirs of the American Mathematical Society** 1990; 317 pp; softcover Volume: 86 ISBN-10: 0-8218-2493-7 ISBN-13: 978-0-8218-2493-1 List Price: US$43 Individual Members: US$25.80 Institutional Members: US$34.40 Order Code: MEMO/86/431
| Requiring background in basic differential topology, this book is aimed at researchers interested in the homotopy type of spaces of smooth embeddings and spaces of diffeomorphisms. The author provides a proof of a useful connectivity estimate in the theory of concordances (or pseudo-isotopies), generalizing Morlet's result from triads to n-ads. The method of proof is a differentiable general position technique analogous to piecewise-linear "sunny collapsing." |