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Topic: Cantor's first proof in DETAILS
Replies: 85   Last Post: Dec 10, 2012 7:23 AM

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 ross.finlayson@gmail.com Posts: 2,720 Registered: 2/15/09
Re: Cantor's first proof in DETAILS
Posted: Dec 9, 2012 11:00 PM

On Dec 9, 7:41 pm, Virgil <vir...@ligriv.com> wrote:
> In article
>  "Ross A. Finlayson" <ross.finlay...@gmail.com> wrote:
>

> > "There's no gap in this Heaviside step with connecting H(0+) and H(0-)
> > with a simple line segment.

>
> Since the H jumps from 0 to 1 at x = 0, tha segeemnt must have endpoints
> (0,0) and (0,1),
> The fiction being claimed to be continuous, for what x does the function
> take the value 1/2?
>

> > There is no point in it such that, not in
> > the function, it is the only point in all neighborhoods of any [1] two
> > points in the function, not in the function (not even a point
> > discontinuity).  Here "in the function" is each (x,y) in the combined
> > coordinate image or co-range, with the function defined by the points
> > in it.

>
>  I do not find enough sense in that to be worth its refutation.
> --

For the vertical line, for which x does the function take any value?
now, either, and neither are vertical lines, and then I'll refer you
back to Euclid and Hardy so you can castigate them for conciliation,
and in apologetics.

No, I well imagine you don't find enough sense that its refutation
would be worth it (to you). Basically it says that, for any two
points in the set of points defining the function, and every, if all
their neighborhoods contain only one point, then the function contains
that point if it is continuous (here, say, reductio continuous). Here
it is that with a piecewise continuous function, that only what would
be the point discontinuities need be analyzed that way, though it
would seem to apply generally. As the defined points in the piecewise
continuous elements go to their endpoint, more and more of their
neighborhoods contain the points on the other side of the point gap.
When all those neighborhoods contain a point, it is defined in the
function (defining the function) for the function to be continuous.
This is simply not far removed from our topological definitions of
continuity, after density: gaplessness.

We've drifted somewhat afield from Cantor's first proof in details and
here with regards to "A function surjects the rationals onto the
irrationals" and "EF as a function has different results than any
other in Cantor's first (and the antidiagonal argument)".

Soup's on.

Regards,

Ross Finlayson

Date Subject Author
11/25/12 ross.finlayson@gmail.com
11/25/12 Virgil
11/25/12 ross.finlayson@gmail.com
11/25/12 Graham Cooper
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11/25/12 Virgil
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11/30/12 Virgil
11/30/12 FredJeffries@gmail.com
11/30/12 ross.finlayson@gmail.com
11/30/12 FredJeffries@gmail.com
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12/1/12 Virgil
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12/5/12 ross.finlayson@gmail.com
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11/30/12 Virgil
11/25/12 Graham Cooper
11/25/12 Virgil
11/25/12 ross.finlayson@gmail.com
11/25/12 Virgil