Re: Replacement of Cardinality (infinite middle)

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Sujet : Re: Replacement of Cardinality (infinite middle)
De : james.g.burns (at) *nospam* att.net (Jim Burns)
Groupes : sci.logic sci.math
Date : 03. Sep 2024, 19:39:15
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <cc00915a-f465-4bfe-a693-7886f561a456@att.net>
References : 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
User-Agent : Mozilla Thunderbird
On 9/2/2024 8:25 PM, Ross Finlayson wrote:
On 09/02/2024 02:46 PM, Jim Burns wrote:

[...]
>
If a well-ordering exists, then,
consider it as a bijective function from ordinal O,
and thus its "elements" or ordinals O,
to domain D.
We are well.ordering the reals, so...
let O = ℶ₁ = |ℝ| = |𝒫(ℕ)|
let D = ℝ
let #: ℝ → ℶ₁: bijective
https://en.wikipedia.org/wiki/Beth_number

As a Cartesian function the usual way, that's thusly
a set of ordered pairs (o, d) which then
via usual axioms and schema of comprehension and
the existence of choice,
read out in order the element (o_alpha, d).
>
So, a well-ordering of the reals, this function, takes
any subset of uncountably many elements (o_alpha, d, alpha).
Now, what's so is that
only countably many of the d can be in their normal order,
that alpha < beta -> d_alpha < d_beta.
...or x,y such that #x < #y  ⇒  x < y

This is because
there are rational numbers between any of those,
and only countably many of those.
I don't see what you're getting at.
In the usual order,
there are rational numbers between any two real numbers,
and only countably many rational numbers,
and uncountably.many real numbers in their usual order.
One doesn't prevent the other.
Maybe there is a different argument available.

Date Sujet#  Auteur
17 Aug 24 * Re: Replacement of Cardinality (infinite middle)46Ross Finlayson
17 Aug 24 +* Re: Replacement of Cardinality (infinite middle)2Ross Finlayson
17 Aug 24 i`- Re: Replacement of Cardinality (infinite middle)1Ross Finlayson
17 Aug 24 `* Re: Replacement of Cardinality (infinite middle)43Jim Burns
18 Aug 24  `* Re: Replacement of Cardinality (infinite middle)42Ross Finlayson
18 Aug 24   `* Re: Replacement of Cardinality (infinite middle)41Jim Burns
18 Aug 24    `* Re: Replacement of Cardinality (infinite middle)40Ross Finlayson
19 Aug 24     `* Re: Replacement of Cardinality (infinite middle)39Jim Burns
19 Aug 24      `* Re: Replacement of Cardinality (infinite middle)38Ross Finlayson
19 Aug 24       +* Re: Replacement of Cardinality (infinite middle)12Jim Burns
19 Aug 24       i+- Re: Replacement of Cardinality (infinite middle)1Ross Finlayson
19 Aug 24       i`* Re: Replacement of Cardinality (infinite middle)10Ross Finlayson
19 Aug 24       i +* Re: Replacement of Cardinality (infinite middle)2Python
20 Aug 24       i i`- Re: Replacement of Cardinality (infinite middle)1Ross Finlayson
20 Aug 24       i `* Re: Replacement of Cardinality (infinite middle)7Jim Burns
20 Aug 24       i  `* Re: Replacement of Cardinality (infinite middle)6Ross Finlayson
20 Aug 24       i   `* Re: Replacement of Cardinality (infinite middle)5Jim Burns
20 Aug 24       i    +* Re: Replacement of Cardinality (infinite middle)3Ross Finlayson
20 Aug 24       i    i`* Re: Replacement of Cardinality (infinite middle)2Python
20 Aug 24       i    i `- Re: Replacement of Cardinality (infinite middle)1Chris M. Thomasson
24 Aug 24       i    `- Re: Replacement of Cardinality (infinite middle)1Ross Finlayson
29 Aug 24       `* Re: Replacement of Cardinality (infinite middle)25Ross Finlayson
30 Aug 24        `* Re: Replacement of Cardinality (infinite middle)24Jim Burns
30 Aug 24         `* Re: Replacement of Cardinality (infinite middle)23Ross Finlayson
30 Aug 24          +* Re: Replacement of Cardinality (infinite middle)21Ross Finlayson
30 Aug 24          i`* Re: Replacement of Cardinality (infinite middle)20Jim Burns
30 Aug 24          i `* Re: Replacement of Cardinality (infinite middle)19Ross Finlayson
30 Aug 24          i  +* Re: Replacement of Cardinality (infinite middle)17Jim Burns
1 Sep 24          i  i`* Re: Replacement of Cardinality (infinite middle)16Ross Finlayson
1 Sep 24          i  i +* Re: Replacement of Cardinality (infinite middle)2Ross Finlayson
30 Dec 24          i  i i`- Re: Replacement of Cardinality (infinite middle)1Ross Finlayson
2 Sep 24          i  i `* Re: Replacement of Cardinality (infinite middle)13Jim Burns
3 Sep 24          i  i  +* Re: Replacement of Cardinality (infinite middle)10Ross Finlayson
3 Sep 24          i  i  i+- Re: Replacement of Cardinality (infinite middle)1Jim Burns
3 Sep 24          i  i  i+- Re: Replacement of Cardinality (infinite middle)1Jim Burns
3 Sep 24          i  i  i`* Re: Replacement of Cardinality (infinite middle)7Jim Burns
5 Sep 24          i  i  i `* Re: Replacement of Cardinality (infinite middle)6Ross Finlayson
5 Sep 24          i  i  i  `* Re: Replacement of Cardinality (infinite middle)5Ross Finlayson
6 Sep 24          i  i  i   +* Re: Replacement of Cardinality (infinite middle)3Jim Burns
6 Sep 24          i  i  i   i`* Re: Replacement of Cardinality (infinite middle)2Ross Finlayson
30 Dec 24          i  i  i   i `- Re: Replacement of Cardinality (infinite middle)1Ross Finlayson
30 Dec 24          i  i  i   `- Re: Replacement of Cardinality (infinite middle)1Ross Finlayson
3 Sep 24          i  i  `* Re: Replacement of Cardinality (infinite middle)2Ross Finlayson
7 Sep 24          i  i   `- Re: Replacement of Cardinality (infinite middle)1Mild Shock
30 Dec 24          i  `- Re: Replacement of Cardinality (infinite middle)1Ross Finlayson
30 Dec 24          `- Re: Replacement of Cardinality (infinite middle)1Ross Finlayson

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