Interesting (IMO) question about the reals...



I'm not certain that this question is well formed, but I will try
asking it anyway.

Given some set-theoretic construction of the real numbers, e.g.
Dedekind cuts, one can divide statements about the reals into two
types: those that are not meaningful in a purely axiomatic treatment,
and those that are. The first type would include, for example, any
statement that refers to the union of a real number, while the second
would include statements that only refer to operations which are
referred to in the real number axioms, such as addition of two reals
or the sup of a bounded set of reals.

My question is this: is it possible that there is a statement of the
second type, which can be proved using Dedekind cuts (or whatever),
but which is not provable from the real number axioms alone?

-Rotwang

.



Relevant Pages

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