Abstract
Throughout this book the term compact group will denote a compact, metrizable group, and a compact Lie group will be a compact (possibly finite) subgroup of some finite-dimensional matrix group over the complex numbers. Any metric δ on a compact group X is assumed to be invariant, i.e. δ(x, x’) = δ(yx, yx’) = δ(xy, x’y) for all x, x’, y ∈ X, and to induce the topology of X. The identity element of a group X will usually be written as 1, 0, 1 X , or 0 X , depending on whether X is multiplicative or additive, and whether there is danger of confusion. If X is a topological group we write X° for its connected component of the identity, C(X) for its centre, Aut(X) for the group of continuous automorphisms of X, and Inn(X) ⊂ Aut(X) for the normal subgroup of inner automorphisms of X. The trivial automorphism of X is denoted by id X =1 Aut(X), and we set Out(X) = Aut(X)/Inn(X). If X is compact and δ is a metric on X we define a metric δ on Aut(X) by setting
for all α, β ∈ Aut(X); the topology on Aut(X) induced by δ is called the uniform topology. If X is a compact Lie group then Aut(X) is again a Lie group in the uniform topology, Inn(X) is an open subgroup of X, and Out(X) is therefore discrete. For an arbitrary compact group X, the group Out(X) is zero-dimensional in the uniform topology ([32]).
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
Author information
Authors and Affiliations
Rights and permissions
Copyright information
© 1995 Birkhäuser Verlag
About this chapter
Cite this chapter
Schmidt, K. (1995). Group actions by automorphisms of compact groups. In: Dynamical Systems of Algebraic Origin. Progress in Mathematics, vol 128. Birkhäuser Basel. https://doi.org/10.1007/978-3-0348-9236-0_1
Download citation
DOI: https://doi.org/10.1007/978-3-0348-9236-0_1
Publisher Name: Birkhäuser Basel
Print ISBN: 978-3-0348-9957-4
Online ISBN: 978-3-0348-9236-0
eBook Packages: Springer Book Archive