We have the following indirect implication of form equivalence classes:

87-alpha \(\Rightarrow\) 362
given by the following sequence of implications, with a reference to its direct proof:

Implication Reference
87-alpha \(\Rightarrow\) 43 clear
43 \(\Rightarrow\) 8 clear
8 \(\Rightarrow\) 361 Zermelo's Axiom of Choice, Moore, 1982, page 325
361 \(\Rightarrow\) 362 Zermelo's Axiom of Choice, Moore, 1982, page 325

Here are the links and statements of the form equivalence classes referenced above:

Howard-Rubin Number Statement
87-alpha:

\(DC(\aleph_{\alpha})\): Given a relation \(R\) such that for every subset \(Y\) of a set \(X\) with \(|Y|<\aleph_{\alpha}\), there is an \(x\in X\) with \(Y\mathrel R x\) then there is a function \(f:\aleph_{\alpha}\to X\) such that (\(\forall\beta < \aleph_{\alpha}\)) \(\{f(\gamma): \gamma < \beta\}\mathrel R f(\beta)\).

43:

\(DC(\omega)\) (DC), Principle of Dependent Choices: 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 Tarski [1948], p 96, Levy [1964], p. 136.

8:

\(C(\aleph_{0},\infty)\):

361:

In \(\Bbb R\), the union of a denumerable number of analytic sets is analytic. G. Moore [1982], pp 181 and 325.

362:

In \(\Bbb R\), every Borel set is analytic. G. Moore [1982], pp 181 and 325.

Comment:

Back