Skip to content

Commit

Permalink
Create \ran macro
Browse files Browse the repository at this point in the history
Signed-off-by: zeramorphic <[email protected]>
  • Loading branch information
zeramorphic committed Feb 16, 2024
1 parent 9e00cbb commit 4fcc200
Show file tree
Hide file tree
Showing 6 changed files with 34 additions and 11 deletions.
4 changes: 2 additions & 2 deletions iii/forcing/01_set_theory.tex
Original file line number Diff line number Diff line change
Expand Up @@ -338,7 +338,7 @@ \subsection{The L\'evy hierarchy}
For the other direction, let \( X \subseteq a \) be a nonempty subset, and consider the pointwise image \( f''X \).
This has a minimal element \( \alpha \), then for any \( z \in X \), if \( f(z) = \alpha \) then for all \( y \in X \), we have \( f(y) \geq \alpha \), so \( \langle y, z \rangle \notin r \).
We then define well-foundedness with a \( \Sigma_1 \) formula as follows.
\[ \exists f.\, \qty(f \text{ is a function} \wedge \forall u \in \operatorname{ran} f.\, (u \in \mathrm{Ord}) \wedge \forall x y \in a.\, (\langle y, x \rangle \in r \to f(y) \in f(x))) \]
\[ \exists f.\, \qty(f \text{ is a function} \wedge \forall u \in \ran f.\, (u \in \mathrm{Ord}) \wedge \forall x y \in a.\, (\langle y, x \rangle \in r \to f(y) \in f(x))) \]
\end{proof}
\begin{proposition}
The following are \( \Delta_0^{\mathsf{ZF}} \).
Expand Down Expand Up @@ -614,7 +614,7 @@ \subsection{Cardinal arithmetic}
\[ \kappa^{\lambda + \mu} = \kappa^\lambda \cdot \kappa^\mu;\quad (\kappa^\lambda)^\mu = \kappa^{\lambda \cdot \mu} \]
\end{lemma}
\begin{definition}
A map between ordinals \( \alpha \to \beta \) is \emph{cofinal} if \( \sup \operatorname{ran} f = \beta \).
A map between ordinals \( \alpha \to \beta \) is \emph{cofinal} if \( \sup \ran f = \beta \).
The \emph{cofinality} of an ordinal \( \gamma \), written \( \cf(\gamma) \), is the least ordinal that admits a cofinal map to \( \gamma \).
A limit ordinal \( \gamma \) is \emph{singular} if \( \cf(\gamma) < \gamma \), and \emph{regular} if \( \cf(\gamma) = \gamma \).
\end{definition}
Expand Down
10 changes: 5 additions & 5 deletions iii/forcing/02_constructibility.tex
Original file line number Diff line number Diff line change
Expand Up @@ -99,7 +99,7 @@ \subsection{G\"odel functions}
\item \( \mathcal F_3(x, y) = x \setminus y \);
\item \( \mathcal F_4(x, y) = x \times y \);
\item \( \mathcal F_5(x, y) = \dom x = \qty{\pi_1(z) \mid z \in x \wedge z \text{ is an ordered pair}} \);
\item \( \mathcal F_6(x, y) = \operatorname{ran} x \qty{\pi_2(z) \mid z \in x \wedge z \text{ is an ordered pair}} \);
\item \( \mathcal F_6(x, y) = \ran x \qty{\pi_2(z) \mid z \in x \wedge z \text{ is an ordered pair}} \);
\item \( \mathcal F_7(x, y) = \qty{\langle u, v, w \rangle \mid \langle u, v \rangle \in x, w \in y} \);
\item \( \mathcal F_8(x, y) = \qty{\langle u, w, v \rangle \mid \langle u, v \rangle \in x, w \in y} \);
\item \( \mathcal F_9(x, y) = \qty{\langle v, u \rangle \in y \in x \mid u = v} \);
Expand Down Expand Up @@ -166,7 +166,7 @@ \subsection{G\"odel functions}
Then
\begin{align*}
\mathcal F_\varphi(a_1, \dots, a_{n-1}) &= \qty{\langle x_{n-1}, \dots, x_1 \rangle \in a_{n-1} \times \dots \times a_1 \mid \varphi(x_1, \dots, x_{n-1})} \\
&= \operatorname{ran}(\qty{\langle 0, x_{n-1}, \dots, x_1 \rangle \in \qty{0} \times a_{n-1} \times \dots \times a_1 \mid \theta(x_1, \dots, x_{n-1}, 0)}) \\
&= \ran(\qty{\langle 0, x_{n-1}, \dots, x_1 \rangle \in \qty{0} \times a_{n-1} \times \dots \times a_1 \mid \theta(x_1, \dots, x_{n-1}, 0)}) \\
&= \mathcal F_6(\mathcal F_\theta(a_1, \dots, a_{n-1}), \mathcal F_1(\mathcal F_3(a_1, a_1), \mathcal F_3(a_1, a_1)), a_1)
\end{align*}
\item If \( \psi(x_1, \dots, x_n) \) is a termed formula and
Expand Down Expand Up @@ -241,7 +241,7 @@ \subsection{G\"odel functions}
The equalities are termed formulas as above, so \( \psi \) is a termed formula.
Then
\begin{align*}
\mathcal F_\varphi(a_1, \dots, a_n) &= \operatorname{ran}\operatorname{ran}\{\langle x_{n+2}, \dots, x_1\rangle \times a_j \times a_i \times a_n \times \dots \times a_1 \\&\quad\quad\quad\mid x_i = x_{n+1} \wedge x_j = x_{n+2} \wedge x_{n+1} \in x_{n+2}\} \\
\mathcal F_\varphi(a_1, \dots, a_n) &= \ran\ran\{\langle x_{n+2}, \dots, x_1\rangle \times a_j \times a_i \times a_n \times \dots \times a_1 \\&\quad\quad\quad\mid x_i = x_{n+1} \wedge x_j = x_{n+2} \wedge x_{n+1} \in x_{n+2}\} \\
&= \mathcal F_6(\mathcal F_6(\mathcal F_\psi(a_1, \dots, a_n), a_1), a_1)
\end{align*}
\end{itemize}
Expand All @@ -261,7 +261,7 @@ \subsection{G\"odel functions}
\end{align*}
So
\begin{align*}
\operatorname{ran}(\mathcal F_{\theta \wedge \psi}\qty(a_1, \dots, a_n, \bigcup a_j)) &= \qty{\langle x_n, \dots, x_1 \rangle \in a_n \times \dots \times a_1 \mid \exists u.\, \langle u, x_n, \dots, x_1 \rangle \in \mathcal F_{\theta \wedge \psi}\qty(a_1, \dots, a_n, \bigcup a_j)} \\
\ran(\mathcal F_{\theta \wedge \psi}\qty(a_1, \dots, a_n, \bigcup a_j)) &= \qty{\langle x_n, \dots, x_1 \rangle \in a_n \times \dots \times a_1 \mid \exists u.\, \langle u, x_n, \dots, x_1 \rangle \in \mathcal F_{\theta \wedge \psi}\qty(a_1, \dots, a_n, \bigcup a_j)} \\
&= \qty{\langle x_n, \dots, x_1 \rangle \in a_n \times \dots \times a_1 \mid \exists x_{n+1} \in x_j.\, \psi(x_1, \dots, x_{n+1})}
\end{align*}
\end{proof}
Expand Down Expand Up @@ -342,7 +342,7 @@ \subsection{The axiom of constructibility}
\[ \forall W.\, \qty(M \cup \qty{M} \subseteq W \wedge \forall x, y \in W.\, \bigwedge_{i \leq 10} \mathcal F_i(x, y) \in W) \to Z \subseteq W \]
The \( \Sigma_1 \) definition will use the inductive definition of the closure.
\begin{align*}
\exists W.\, W \text{ is a function} &\wedge \dom W = \omega \wedge Z = \bigcup \operatorname{ran} W \\
\exists W.\, W \text{ is a function} &\wedge \dom W = \omega \wedge Z = \bigcup \ran W \\
&\wedge W(0) = M \wedge W(n) \subseteq W(n+1) \\
&\wedge \qty(\forall x, y \in W(n).\, \bigwedge_{i \leq 10} \mathcal F_i(x, y) \in W(n+1)) \\
&\wedge \qty(\forall z \in W(n+1).\, \exists x, y \in W(n).\, \bigvee_{i \leq 10} z = \mathcal F_i(x, y))
Expand Down
6 changes: 3 additions & 3 deletions iii/forcing/03_forcing.tex
Original file line number Diff line number Diff line change
Expand Up @@ -90,7 +90,7 @@ \subsection{Forcing posets}
\end{proposition}
\begin{example}
For sets \( I, J \), we let \( \operatorname{Fn}(I, J) \) denote the set of all finite partial functions from \( I \) to \( J \).
\[ \operatorname{Fn}(I, J) = \qty{p \mid \abs{p} < \omega \wedge p \text{ is a function} \wedge \dom p \subseteq I \wedge \operatorname{ran} p \subseteq J} \]
\[ \operatorname{Fn}(I, J) = \qty{p \mid \abs{p} < \omega \wedge p \text{ is a function} \wedge \dom p \subseteq I \wedge \ran p \subseteq J} \]
We let \( \leq \) be the reverse inclusion on \( \operatorname{Fn}(I, J) \), so \( q \leq p \) if and only if \( q \supseteq p \).
The maximal element \( \Bbbone \) is the empty set.
Then \( (\operatorname{Fn}(I, J), \leq, \varnothing) \) is a forcing poset, and moreover, the preorder is separative.
Expand Down Expand Up @@ -204,7 +204,7 @@ \subsection{Dense sets and genericity}
Then for all \( i \in I \) and \( j \in J \), the following are dense.
\begin{enumerate}
\item \( D_i = \qty{q \in \operatorname{Fn}(I, J) \mid i \in \dom q} \);
\item \( R_j = \qty{q \in \operatorname{Fn}(I, J) \mid j \in \operatorname{ran} q} \).
\item \( R_j = \qty{q \in \operatorname{Fn}(I, J) \mid j \in \ran q} \).
\end{enumerate}
\end{example}
\begin{definition}
Expand Down Expand Up @@ -277,7 +277,7 @@ \subsection{Names}
\( \mathbb P \)-names are denoted with overdots, such as in \( \dot x \).
\begin{definition}
The \emph{range} of a \( \mathbb P \)-name \( \dot x \) is
\[ \operatorname{ran}(\dot x) = \qty{\dot y \mid \exists p \in \mathbb P \mid \langle p, \dot y \rangle \in \dot x} \]
\[ \ran(\dot x) = \qty{\dot y \mid \exists p \in \mathbb P \mid \langle p, \dot y \rangle \in \dot x} \]
\end{definition}
\begin{remark}
Alternatively, by transfinite recursion on rank, we could define the class of \( \mathbb P \)-names over \( \mathrm{V} \) in the following way.
Expand Down
2 changes: 1 addition & 1 deletion iii/lc/01_inaccessible_cardinals.tex
Original file line number Diff line number Diff line change
Expand Up @@ -51,7 +51,7 @@ \subsection{Large cardinal properties}
Cantor's theorem shows that \( \aleph_\alpha \leq \beth_\alpha \), and the continuum hypothesis is the assertion that \( \aleph_1 = \beth_1 \).
Note that \( \kappa \) is a strong limit cardinal if and only if \( \kappa = \beth_\lambda \) for some limit ordinal \( \lambda \).
In particular, \( \mathsf{ZFC} \vdash \Sigma \mathsf{C} \).
\item If \( s : n \to \omega \) for \( n < \omega \), then \( \sup(s) = \bigcup \operatorname{ran}(s) < \omega \).
\item If \( s : n \to \omega \) for \( n < \omega \), then \( \sup(s) = \bigcup \ran(s) < \omega \).
This gives rise to the following definition.
\begin{definition}
Let \( \lambda \) be a limit ordinal.
Expand Down
22 changes: 22 additions & 0 deletions iii/lc/main.tex
Original file line number Diff line number Diff line change
Expand Up @@ -15,4 +15,26 @@ \section{Inaccessible cardinals}
\section{Measurable cardinals}
\input{02_measurable_cardinals.tex}

\newpage
\section*{Diagram of large cardinal properties}
Under suitable consistency assumptions, large cardinal properties that appear in higher positions on this diagram have strictly higher consistency strength than properties appearing lower down the diagram.
% https://q.uiver.app/#q=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
\[\begin{tikzcd}
& {\mathsf{SC}(\kappa)} \\
{\mathsf{Ulam}(\kappa)} & {\mathsf{M}(\kappa)} & {\mathsf{RVM}(\kappa)} \\
{\mathsf{WC}(\kappa)} & {\mathsf{W}(\kappa)} \\
& {\mathsf{I}(\kappa)} & {\mathsf{WI}(\kappa)} \\
& {\mathsf{Wor}(\kappa)}
\arrow[from=1-2, to=2-2]
\arrow[from=2-2, to=2-3]
\arrow[from=2-3, to=4-3]
\arrow[from=2-2, to=3-2]
\arrow[from=3-2, to=4-2]
\arrow[from=4-2, to=4-3]
\arrow[from=4-2, to=5-2]
\arrow[tail reversed, from=3-1, to=3-2]
\arrow[shift left=2, from=2-2, to=2-1]
\arrow["{\text{min.}}", shift left=2, from=2-1, to=2-2]
\end{tikzcd}\]

\end{document}
1 change: 1 addition & 0 deletions util.sty
Original file line number Diff line number Diff line change
Expand Up @@ -223,6 +223,7 @@
\DeclareMathOperator{\res}{res}
\DeclareMathOperator{\Con}{Con}
\DeclareMathOperator{\cf}{cf}
\DeclareMathOperator{\ran}{ran}
% https://github.com/wspr/unicode-math/issues/457
\AtBeginDocument{%
\newcommand{\dashrightarrow}{\mathrel{\rightdasharrow}}
Expand Down

0 comments on commit 4fcc200

Please sign in to comment.