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| author | adelon <22380201+adelon@users.noreply.github.com> | 2025-07-07 18:46:39 +0200 |
|---|---|---|
| committer | adelon <22380201+adelon@users.noreply.github.com> | 2025-07-07 18:46:39 +0200 |
| commit | 054ed649d975a05602439addfa610bea68fbf3d4 (patch) | |
| tree | 56e4a2c786bed38a2ec5b233577fcc5546a08e28 /library/topology | |
| parent | 5c9507fca014a81f9a694b31f3b2bdca71c2291c (diff) | |
Clean whitespace, add TODO
Diffstat (limited to 'library/topology')
| -rw-r--r-- | library/topology/topological-space.tex | 25 |
1 files changed, 12 insertions, 13 deletions
diff --git a/library/topology/topological-space.tex b/library/topology/topological-space.tex index 409e107..6ddf721 100644 --- a/library/topology/topological-space.tex +++ b/library/topology/topological-space.tex @@ -230,7 +230,7 @@ Follows by \cref{inters_singleton,closure}. \end{proof} -\begin{proposition}\label{subseteq_inters_iff_to_right} +\begin{proposition}\label{subseteq_inters_iff_to_right} Let $A,F$ be sets. Suppose $A \subseteq \inters{F}$. Then for all $X \in F$ we have $A \subseteq X$. @@ -250,7 +250,7 @@ -\begin{proposition}\label{subseteq_inters_iff_to_left} +\begin{proposition}\label{subseteq_inters_iff_to_left} Let $A,F$ be sets. Suppose $F$ is inhabited. % TODO:Remove!! Suppose for all $X \in F$ we have $A \subseteq X$. @@ -261,7 +261,7 @@ \caseOf{$A = \emptyset$.}Trivial. \caseOf{$A \neq \emptyset$.} $F$ is inhabited. - It suffices to show that for all $a \in A$ we have $a \in \inters{F}$. + It suffices to show that for all $a \in A$ we have $a \in \inters{F}$. Fix $a \in A$. For all $X \in F$ we have $a \in X$. $A \subseteq \unions{F}$. @@ -269,7 +269,7 @@ \end{byCase} \end{proof} -\begin{proposition}\label{subseteq_inters_iff_new} +\begin{proposition}\label{subseteq_inters_iff_new} Suppose $F$ is inhabited. $A \subseteq \inters{F}$ iff for all $X \in F$ we have $A \subseteq X$. \end{proposition} @@ -281,7 +281,7 @@ \end{proposition} \begin{proof} \begin{byCase} - \caseOf{$A = \emptyset$.} + \caseOf{$A = \emptyset$.} Trivial. \caseOf{$A \neq \emptyset$.} We show that $\carrier[X] \in \closures{A}{X}$. @@ -289,7 +289,7 @@ $\carrier[X]$ is closed in $X$. $\carrier[X] \in \pow{\carrier[X]}$. \end{subproof} - $\closures{A}{X}$ is inhabited. + $\closures{A}{X}$ is inhabited. For all $A' \in \closures{A}{X}$ we have $A \subseteq A'$. Therefore $A \subseteq \inters{\closures{A}{X}}$. \end{byCase} @@ -389,7 +389,7 @@ There exist $U' \in F'$ such that $U' = \carrier[X] \setminus U$. Omitted. \caseOf{$\inters{F} \neq \emptyset$.} - + Fix $a \in \carrier[X] \setminus (\unions{F'})$. $\inters{F}$ is inhabited. $a \in \carrier[X]$. @@ -414,7 +414,7 @@ \end{proposition} \begin{proof} \begin{byCase} - \caseOf{$\closure{A}{X} = \emptyset$.} + \caseOf{$\closure{A}{X} = \emptyset$.} Trivial. \caseOf{$\closure{A}{X} \neq \emptyset$.} $\closures{A}{X}$ is inhabited. @@ -429,7 +429,7 @@ \begin{proposition}\label{closure_is_minimal_closed_set} Let $X$ be a topological space. Suppose $A \subseteq \carrier[X]$. - For all $Y \in \closeds{X}$ such that $A \subseteq Y$ we have $\closure{A}{X} \subseteq Y$. + For all $Y \in \closeds{X}$ such that $A \subseteq Y$ we have $\closure{A}{X} \subseteq Y$. \end{proposition} \begin{proof} Follows by \cref{closure,closeds,inters_subseteq_elem,closures}. @@ -449,21 +449,20 @@ \begin{proof} We show that for all $x \in \carrier[X]\setminus\interior{A}{X}$ we have $x \in \closure{(\carrier[X]\setminus A)}{X}$. \begin{subproof} - Fix $x \in \carrier[X]\setminus\interior{A}{X}$. - Suppose not. + Suppose not. $x \notin \closure{(\carrier[X]\setminus A)}{X}$. $x \in \carrier[X]$. $(\carrier[X] \setminus \closure{(\carrier[X]\setminus A)}{X}) \inter \closure{(\carrier[X]\setminus A)}{X} = \emptyset$. $x \in A$. $x \in A \inter (\carrier[X] \setminus \closure{(\carrier[X]\setminus A)}{X})$. $\carrier[X] \setminus \closure{(\carrier[X]\setminus A)}{X} \in \opens[X]$. - There exist $U \in \opens[X]$ such that $x \in U$ and $U\subseteq A$. + There exist $U \in \opens[X]$ such that $x \in U$ and $U\subseteq A$. $U \subseteq \interior{A}{X}$. Contradiction. \end{subproof} $\carrier[X]\setminus\interior{A}{X} \subseteq \closure{(\carrier[X]\setminus A)}{X}$. - $\closure{(\carrier[X]\setminus A)}{X} \subseteq \carrier[X]\setminus\interior{A}{X}$. + $\closure{(\carrier[X]\setminus A)}{X} \subseteq \carrier[X]\setminus\interior{A}{X}$. % SLOW by \cref{setminus_subseteq,interior_is_open,complement_of_open_elem_closeds,subseteq_implies_setminus_supseteq,closure_is_minimal_closed_set}. \end{proof} |
