We have the following indirect implication of form equivalence classes:
Implication | Reference |
---|---|
149 \(\Rightarrow\) 67 |
The axiom of choice in topology, Brunner, N. 1983d, Notre Dame J. Formal Logic note-26 |
67 \(\Rightarrow\) 126 | clear |
126 \(\Rightarrow\) 82 | note-76 |
82 \(\Rightarrow\) 83 |
Definitions of finite, Howard, P. 1989, Fund. Math. |
Here are the links and statements of the form equivalence classes referenced above:
Howard-Rubin Number | Statement |
---|---|
149: | \(A(F)\): Every \(T_2\) topological space is a continuous, finite to one image of an \(A1\) space. |
67: | \(MC(\infty,\infty)\) \((MC)\), The Axiom of Multiple Choice: For every set \(M\) of non-empty sets there is a function \(f\) such that \((\forall x\in M)(\emptyset\neq f(x)\subseteq x\) and \(f(x)\) is finite). |
126: | \(MC(\aleph_0,\infty)\), Countable axiom of multiple choice: For every denumerable set \(X\) of non-empty sets there is a function \(f\) such that for all \(y\in X\), \(f(y)\) is a non-empty finite subset of \(y\). |
82: | \(E(I,III)\) (Howard/Yorke [1989]): If \(X\) is infinite then \(\cal P(X)\) is Dedekind infinite. (\(X\) is finite \(\Leftrightarrow {\cal P}(X)\) is Dedekind finite.) |
83: | \(E(I,II)\) Howard/Yorke [1989]: \(T\)-finite is equivalent to finite. |
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