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Topic: Joel David Hamkins on definable real numbers in analysis
Replies: 98   Last Post: Jun 30, 2013 3:22 PM

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David C. Ullrich

Posts: 3,019
Registered: 12/13/04
Re: Joel David Hamkins on definable real numbers in analysis
Posted: Jun 26, 2013 11:48 AM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply

On Tue, 25 Jun 2013 13:43:36 -0700 (PDT), mueckenh@rz.fh-augsburg.de
wrote:

>On Tuesday, 25 June 2013 17:07:36 UTC+2, dull...@sprynet.com wrote:
>>> There are not uncountably many reals, neither in the natural order nor in the well-order.
>
>

>> That's very funny.
>
>That's easily provable:
>
>Consider a Cantor-list that contains a complete sequence (q_k) of all
>rational numbers q_k. The first n digits of the anti-diagonal d are
>d_1, d_2, d_3, ..., d_n. It can be shown *for every n* that the Cantor-
>list beyond line n contains infinitely many rational numbers q_k that
>have the same sequence of first n digits as the anti-diagonal d.
>
>Proof: There are infinitely many rationals q_k with this property. All
>are in the list by definition. At most n of them are in the first n
>lines of the list. Infinitely many must exist in the remaining part of
>the list. So we have obtained:
>
>For all n exists k:
>d_1, d_2, d_3, ..., d_n = q_k1, q_k2, q_k3, ..., q_kn.
>This theorem it is not less important than Cantor's theorem: For all
>k: d =/= q_k.
>
>Both theorems contradict each other


Erm, no they don't. If your "for every n there exists k such that"
was instead "there exists k such that for every n" then they
would contradict each other.

Don't feel bad about this. Confusing the order of quantifiers
that way is very common among people who haven't learned
to reason carefully.


>with the result that finished
>infinity as presumed for transfinite set theory is not a valid
>mathematical notion.
>
>Regards, WM




Date Subject Author
6/18/13
Read Joel David Hamkins on definable real numbers in analysis
fom
6/19/13
Read Re: Joel David Hamkins on definable real numbers in analysis
David Petry
6/19/13
Read Re: Joel David Hamkins on definable real numbers in analysis
fom
6/19/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/19/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Peter Percival
6/19/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/19/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/19/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Tucsondrew@me.com
6/21/13
Read Re: Joel David Hamkins on definable real numbers in analysis
David C. Ullrich
6/21/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/21/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/22/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/22/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/22/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/22/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/22/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/22/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Tucsondrew@me.com
6/22/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/22/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Tucsondrew@me.com
6/23/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/23/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Tucsondrew@me.com
6/23/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Tucsondrew@me.com
6/23/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/23/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Tucsondrew@me.com
6/23/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/23/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/24/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/23/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/22/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/23/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/23/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/23/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/23/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/24/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/24/13
Read Re: WM screws up the notion of a limit!
Virgil
6/25/13
Read Re: WM screws up the notion of a limit!
Virgil
6/25/13
Read Re: WM screws up the notion of a limit!
Virgil
6/26/13
Read Re: WM screws up the notion of a limit!
Virgil
6/26/13
Read Re: WM screws up the notion of a limit!
fom
6/26/13
Read Re: WM screws up the notion of a limit!
Virgil
6/22/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/22/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Tucsondrew@me.com
6/22/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/22/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/22/13
Read Re: Joel David Hamkins on definable real numbers in analysis
David C. Ullrich
6/22/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/22/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/23/13
Read Re: Joel David Hamkins on definable real numbers in analysis
David C. Ullrich
6/23/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/23/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/24/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/24/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/25/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/25/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/24/13
Read Re: Joel David Hamkins on definable real numbers in analysis
David C. Ullrich
6/24/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/24/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/25/13
Read Re: Joel David Hamkins on definable real numbers in analysis
David C. Ullrich
6/25/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/25/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/26/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/26/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/25/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Tucsondrew@me.com
6/26/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/26/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/25/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Ralf Bader
6/26/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/26/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/26/13
Read Re: Joel David Hamkins on definable real numbers in analysis
David C. Ullrich
6/26/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/26/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/27/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/27/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/26/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/27/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/27/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/28/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/28/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Tucsondrew@me.com
6/28/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/28/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Tucsondrew@me.com
6/28/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/28/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Tucsondrew@me.com
6/29/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/29/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/30/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/28/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/29/13
Read Re: Joel David Hamkins on definable real numbers in analysis
mueckenh@rz.fh-augsburg.de
6/29/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/28/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/28/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/19/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil
6/19/13
Read Re: Joel David Hamkins on definable real numbers in analysis
Virgil

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