학술논문
Wiedersehen metrics and exotic involutions of Euclidean spheres
Document Type
research-article
Author
Source
Journal für die reine und angewandte Mathematik. 2007(605):1-21
Subject
Language
English
ISSN
1435-5345
0075-4102
0075-4102
Abstract
We provide explicit, simple, geometric formulas for free involutions ρ of Euclidean spheres that are not conjugate to the antipodal involution. Therefore the quotient Sn/ρ is a manifold that is homotopically equivalent but not diffeomorphic to . We use these formulas for constructing explicit non-trivial elements in π1 Diff(S5) and π1 Diff(S13) and to provide explicit formulas for non-cancellation phenomena in group actions.