Compare commits
2 commits
24ed36d0a7
...
dfd9be7925
Author | SHA1 | Date | |
---|---|---|---|
dfd9be7925 | |||
236874b1a5 |
3 changed files with 6 additions and 5 deletions
|
@ -199,8 +199,8 @@
|
|||
\[
|
||||
D \subseteq \N^\N \mathbin{\text{\reflectbox{$\coloneqq$}}} \cN
|
||||
\]
|
||||
and a continuous bijection from
|
||||
$D$ onto $X$ (the inverse does not need to be continuous).
|
||||
and a continuous bijection $f\colon D \to X$
|
||||
(the inverse does not need to be continuous).
|
||||
|
||||
Moreover there is a continuous surjection $g: \cN \to X$
|
||||
extending $f$.
|
||||
|
|
|
@ -64,7 +64,7 @@
|
|||
|
||||
Take $S \coloneqq \{s \in \N^{<\N}: \exists x \in D, n \in \N.~x\defon{n} = s\}$.
|
||||
Clearly $S$ is a pruned tree.
|
||||
Moreover, since $D$ is closed, we have that (cf.~\yaref{s3e1})
|
||||
Moreover, since $D$ is closed, we have that\footnote{cf.~\yaref{s3e1}}
|
||||
\[
|
||||
D = [S] = \{x \in \N^\N : \forall n \in \N.~x\defon{n} \in S\}.
|
||||
\]
|
||||
|
|
|
@ -1,5 +1,4 @@
|
|||
\subsection{The Ellis semigroup}
|
||||
% TODO ANKI-MARKER
|
||||
\lecture{17}{2023-12-12}{The Ellis semigroup}
|
||||
|
||||
Let $(X, d)$ be a compact metric space
|
||||
|
@ -75,7 +74,7 @@ Properties of $(X,T)$ translate to properties of $E(X,T)$:
|
|||
\]
|
||||
\end{claim}
|
||||
\begin{subproof}
|
||||
\todo{Homework}
|
||||
Cf.~\yaref{s11e1}
|
||||
\end{subproof}
|
||||
|
||||
Let $g \in G$.
|
||||
|
@ -163,6 +162,8 @@ But it is interesting for other semigroups.
|
|||
\todo{The other direction is left as an easy exercise.}
|
||||
\end{proof}
|
||||
|
||||
% TODO ANKI-MARKER
|
||||
|
||||
Let $(X,T)$ be a flow.
|
||||
Then by Zorn's lemma, there exists $X_0 \subseteq X$
|
||||
such that $(X_0, T)$ is minimal.
|
||||
|
|
Loading…
Reference in a new issue