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Topic: Only for mathematicians!
Replies: 2   Last Post: Aug 28, 2014 8:57 PM

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Ben Bacarisse

Posts: 1,972
Registered: 7/4/07
Re: Only for mathematicians!
Posted: Aug 28, 2014 4:20 PM
  Click to see the message monospaced in plain text Plain Text   Click to reply to this topic Reply writes:

> On Thursday, 28 August 2014 19:23:14 UTC+2, Virgil wrote:
>> False! Cantor said that the naturals collectively could index the
>> collection of positive rationals, not the one natural could do it all.

> Nonsense. How would he do that?

Bu showing, as you and other have done here, an explicit bijection from N
to Q (or Q+).

> There is no other way than to show
> something for all naturl nunbers (or to show it for every natural
> number and to claim that it was shown for all).

Watch the pea, see the shells move. Is under any? Is not under all?
Is it not under every shell?

> Cantor shows that every natural is mapped on a rational and vice
> versa.

A fact of set theory and of WMaths.

> I show that every natural n that according to Cantor is mapped on a
> rational q_n, in another mapping is mapped on an infinite set s_n of
> not indexed rationals les than n.

A fact of set theory and of WMaths.

What is missing (again and again) is a formula that's true is set theory
and false in WMaths. Same maths, deceptive words.


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