src/ZF/Constructible/document/root.tex
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Fri, 01 Aug 2025 20:01:55 +0200
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\documentclass[11pt,a4paper]{article}
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\usepackage[T1]{fontenc}
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\usepackage{graphicx}
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\usepackage{isabelle,amssymb,isabellesym}
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\usepackage{pdfsetup}\urlstyle{rm}
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%table of contents is too crowded!
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\usepackage{tocloft}
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\addtolength\cftsubsecnumwidth {0.5em}
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\addtolength\cftsubsubsecnumwidth {1.0em}
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\begin{document}
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\title{The Constructible Universe\\ and the\\
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       Relative Consistency of the Axiom of Choice}
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\author{Lawrence C Paulson}
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\maketitle
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\begin{abstract}
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  G\"odel's proof of the relative consistency of the axiom of
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  choice~\cite{goedel40} is one of the most important results in the
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  foundations of mathematics. It bears on Hilbert's first problem, namely the
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  continuum hypothesis, and indeed G\"odel also proved the relative
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  consistency of the continuum hypothesis. Just as important, G\"odel's proof
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  introduced the \emph{inner model} method of proving relative consistency,
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  and it introduced the concept of \emph{constructible
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    set}. Kunen~\cite{kunen80} gives an excellent description of this body of
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  work.
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  This Isabelle/ZF formalization demonstrates G\"odel's claim that his proof
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  can be undertaken without using metamathematical arguments, for example
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  arguments based on the general syntactic structure of a formula. Isabelle's
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  automation replaces the metamathematics, although it does not eliminate the
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  requirement at least to state many tedious results that would otherwise be
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  unnecessary.
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  This formalization~\cite{paulson-consistency} is by far the deepest result
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  in set theory proved in any automated theorem prover. It rests on a previous
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  formal development of the reflection theorem~\cite{paulson-reflection}.
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\end{abstract}
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\tableofcontents
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\begin{center}
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  \includegraphics[scale=0.7]{session_graph}
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\end{center}
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\newpage
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\parindent 0pt\parskip 0.5ex
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\input{session}
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\bibliographystyle{plain}
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\bibliography{root}
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\end{document}