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> the Cantor space, where 0.9999... and 1.0000... are actually distinct value

What do you mean here? The Cantor set is a subspace, not a cover, of [0, 1]; values in the Cantor set that are the same in [0, 1] are also the same in the Cantor set.



Sure, the Cantor set is the set of real numbers in [0,1] with trinary expansions that do not contain 1 at any point.

A Cantor space is any set that can be mapped to (and from) the Cantor set.

The Cantor space is the set of infinitely long bitstrings; instead of a trinary number 0.200220222200..., you'd conceive of the same entity as the string "100110111100...". The mapping is pretty obvious.

0.99999... and 1.0000... are neither of them bitstrings, so it's not really clear what cvoss was thinking of. But it's certainly true that "0999999..." and "1000000..." are distinct strings.

Going back to the Cantor set, you'd usually represent 1 as 0.22222222... for obvious reasons of consistency (that is the only format matching the representation of the rest of the set). It would be weird to represent it as 1.000000000...; that would look like you were considering the left end of the Cantor set in [1,2] rather than the right end of the Cantor set in [0,1].




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