This non-implication,
Form 29 \( \not \Rightarrow \)
Form 183-alpha,
whose code is 4, is constructed around a proven non-implication as follows:
Hypothesis | Statement |
---|---|
Form 43 | <p> \(DC(\omega)\) (DC), <strong>Principle of Dependent Choices:</strong> If \(S\) is a relation on a non-empty set \(A\) and \((\forall x\in A) (\exists y\in A)(x S y)\) then there is a sequence \(a(0), a(1), a(2), \ldots\) of elements of \(A\) such that \((\forall n\in\omega)(a(n)\mathrel S a(n+1))\). See <a href="/articles/Tarski-1948">Tarski [1948]</a>, p 96, <a href="/articles/Levy-1964">Levy [1964]</a>, p. 136. </p> |
Conclusion | Statement |
---|---|
Form 183-alpha | <p> There are no \(\aleph_{\alpha}\) minimal sets. That is, there are no sets \(X\) such that <ol type="1"> <li>\(|X|\) is incomparable with \(\aleph_{\alpha}\)</li> <li>\(\aleph_{\beta}<|X|\) for every \(\beta < \alpha \) and</li> <li>\(\forall Y\subseteq X, |Y|<\aleph_{\alpha}\) or \(|X-Y| <\aleph_{\alpha}\).</li> </ol> </p> |
The conclusion Form 29 \( \not \Rightarrow \) Form 183-alpha then follows.
Finally, the
List of models where hypothesis is true and the conclusion is false:
Name | Statement |
---|---|
\(\cal N27\) Hickman's Model II | Let \(A\) be a set with cardinality\(\aleph_1\) such that \(A=\{(a_{\alpha},b_{\beta}) : \alpha < \omega, \beta< \omega_1\}\) |