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On 9/17/2024 2:57 PM, Ross Finlayson wrote:Actually it's that really it's the "distinct/continuous"On 09/17/2024 10:59 AM, Jim Burns wrote:>>[...]>
I do seem to recall that
your account was around when it was set out,
for example,
that least-upper-bound is nice neat trivial next,
In ℕ and ℤ
there are integers next to each other,
which is to say,
there are integers with no other integers between.
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In ℚ
there are no rationals next to each other,
because
there are no rationals with no rationals between.
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In ℝ
there are no reals next to each other,
because,
however close |x-y| = d > 0 is,
there are no d.sized gaps in the rationals,
so there must be rationals between.
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The least.upper.bound of (0,1) is 1
but 1 isn't next to any element of (0,1)
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Unlike ℕ and ℤ, ℚ and ℝ do not 'next'.
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