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-rw-r--r--library/topology/metric-space.tex93
-rw-r--r--library/topology/order-topology.tex33
2 files changed, 126 insertions, 0 deletions
diff --git a/library/topology/metric-space.tex b/library/topology/metric-space.tex
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+\import{topology/topological-space.tex}
+\import{numbers.tex}
+\import{function.tex}
+
+\section{Metric Spaces}
+
+\begin{definition}\label{metric}
+ $f$ is a metric on $M$ iff $f$ is a function from $M \times M$ to $\reals$ and
+ for all $x,y,z \in M$ we have
+ $f(x,x) = \zero$ and
+ $f(x,y) = f(y,x)$ and
+ $f(x,y) \leq f(x,z) + f(z,y)$ and
+ if $x \neq y$ then $\zero < f(x,y)$.
+\end{definition}
+
+\begin{definition}\label{open_ball}
+ $\openball{r}{x}{f} = \{z \in M \mid \text{ $f$ is a metric on $M$ and $f(x,z) < r$ } \}$.
+\end{definition}
+
+%TODO: \metric_opens{d} = {hier die construction für topology}
+%TODO: Die induzierte topology definieren und dann in struct verwenden.
+
+
+\begin{struct}\label{metric_space}
+ A metric space $M$ is a onesorted structure equipped with
+ \begin{enumerate}
+ \item $\metric$
+ \end{enumerate}
+ such that
+ \begin{enumerate}
+ \item \label{metric_space_metric} $\metric[M]$ is a metric on $M$.
+ \item \label{metric_space_topology} $M$ is a topological space.
+ \item \label{metric_space_opens} for all $x \in M$ for all $r \in \reals$ $\openball{r}{x}{\metric[M]} \in \opens[M]$.
+ \end{enumerate}
+\end{struct}
+
+\begin{abbreviation}\label{descriptive_syntax_for_openball1}
+ $U$ is an open ball in $M$ of $x$ with radius $r$ iff $x \in M$ and $M$ is a metric space and $U = \openball{r}{x}{\metric[M]}$.
+\end{abbreviation}
+
+\begin{abbreviation}\label{descriptive_syntax_for_openball2}
+ $U$ is an open ball in $M$ iff there exist $x \in M$ such that there exist $r \in \reals$ such that $U$ is an open ball in $M$ of $x$ with radius $r$.
+\end{abbreviation}
+
+\begin{lemma}\label{union_of_open_balls_is_open}
+ Let $M$ be a metric space.
+ For all $U,V \subseteq M$ if $U$ is an open ball in $M$ and $V$ is an open ball in $M$ then $U \union V$ is open in $M$.
+\end{lemma}
+
+
+%\begin{definition}\label{lenght_of_interval} %TODO: take minus if its implemented
+% $\lenghtinterval{x}{y} = r$
+%\end{definition}
+
+
+
+
+
+\begin{lemma}\label{metric_implies_topology}
+ Let $M$ be a set, and let $f$ be a metric on $M$.
+ Then $M$ is a metric space.
+\end{lemma}
+
+
+
+
+
+%\begin{struct}\label{metric_space}
+% A metric space $M$ is a onesorted structure equipped with
+% \begin{enumerate}
+% \item $\metric$
+% \end{enumerate}
+% such that
+% \begin{enumerate}
+% \item \label{metric_space_d} $\metric[M]$ is a function from $M \times M$ to $\reals$.
+% \item \label{metric_space_distence_of_a_point} $\metric[M](x,x) = \zero$.
+% \item \label{metric_space_positiv} for all $x,y \in M$ if $x \neq y$ then $\zero < \metric[M](x,y)$.
+% \item \label{metric_space_symetrie} $\metric[M](x,y) = \metric[M](y,x)$.
+% \item \label{metric_space_triangle_equation} for all $x,y,z \in M$ $\metric[M](x,y) < \metric[M](x,z) + \metric[M](z,y)$ or $\metric[M](x,y) = \metric[M](x,z) + \metric[M](z,y)$.
+% \item \label{metric_space_topology} $M$ is a topological space.
+% \item \label{metric_space_opens} for all $x \in M$ for all $r \in \reals$ $\{z \in M \mid \metric[M](x,z) < r\} \in \opens$.
+% \end{enumerate}
+%\end{struct}
+
+%\begin{definition}\label{open_ball}
+% $\openball{r}{x}{M} = \{z \in M \mid \metric(x,z) < r\}$.
+%\end{definition}
+
+%\begin{proposition}\label{open_ball_is_open}
+% Let $M$ be a metric space,let $r \in \reals $, let $x$ be an element of $M$.
+% Then $\openball{r}{x}{M} \in \opens[M]$.
+%\end{proposition}
+
diff --git a/library/topology/order-topology.tex b/library/topology/order-topology.tex
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+\import{topology/topological-space.tex}
+\import{order/order.tex}
+
+\section{Order Topology}
+
+\begin{abbreviation}\label{open_interval}
+ $z \in \oointervalof{x}{y}$ iff $x \mathrel{R} y$ and $x \mathrel{R} z$ and $z \mathrel{R} y$.
+ %$\oointervalof{x}{y}{X} = \{ z \mid x \in X, y \in X, z \in X x \mathrel{R} y \wedge x \mathrel{R} z \wedge z \mathrel{R} y\}$.
+\end{abbreviation}
+
+\begin{struct}\label{order_topology}
+ A ordertopology space $X$ is a onesorted structure equipped with
+ \begin{enumerate}
+ \item $<$
+ \end{enumerate}
+ such that
+ \begin{enumerate}
+ \item \label{order_topology_1} $<$ is a strict order on $X$
+ \item \label{order_topology_2}
+ \item \label{order_topology_3}
+ \item \label{order_topology_4}
+ \item \label{order_topology}
+ \item \label{order_topology}
+ \item \label{order_topology}
+ \end{enumerate}
+\end{struct}
+
+
+
+%\begin{definition}\label{order_topology}
+% $X$ has the order topology iff for all $x,y \in X$ $X$ has a strict order $R$ and $\oointervalof{x}{y}{X} \in \opens[X]$ and $X$ is a topological space.
+% %$O$ is the order Topology on $X$ iff for all $x,y \in X$ $X$ has a strict order $R$ and $(x,y) \in O$ and $O$ is .
+%\end{definition}