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

 Messages: [ Previous | Next ]
 Virgil Posts: 8,833 Registered: 1/6/11
Re: Cantor's first proof in DETAILS
Posted: Dec 3, 2012 1:39 AM

In article
"Ross A. Finlayson" <ross.finlayson@gmail.com> wrote:

> Card(N) isn't a real quantity.

Neither, in a very primitive sense, are 1, 2 and 3. The naturals are
precursors of both the integers and the positive rationals, both of
which are precursor to the rational field which is itself a precursor
to the reals.

But Card(N) is real property, i.e., one which really exists.

> So what you say there is wrong, though
> it's wrong twice.

Only when I copy what you say.

> Though if you're interested in the real point at
> infinity, well, you should be able to find description of number-
> theory's point at infinity or one- or two-point compactification of
> the reals and integers (in the projectively extended real numbers).
> Cardinals are defined by themselves, don't be putting them where they
> don't go, those aren't compatible types.

Are you claiming that one cannot speak of the cardinality of the
naturals, or rationals, or reals? That you may not know how does not
mean others are all equally ignorant.
>
> There are only and everywhere real numbers between zero and one.

There cannot be 'only and everywhere' numbers that are constrained not
to be anywhere except between zero and one.

> Here, 0 < EF(1) < 1.
But according to Ross very own definition of his alleged EF, one can
show that for every n in |N and every positive epsilon, that EF(n) <
epsilon.

> The arithmetic of iota-values, representing values
> from the continuum, of real numbers, is different for the operations
> as addition, and multiplication, simply as repeated addition.

Repeated addition, adding two numbers then adding the third , then the
fourth, etc., works fine, though a bit tediously, for all number
systems contained in the reals. Or even contained in the complexes or
quaternions or octonions, or vector spaces, for that mater..
>
> Dirac's delta is regularly used in real analysis, for example in the
> solutions of differential equations.

When it is used, the analysis is not quite real as it is not a real
function.

> Heaviside's step can be seen as continuous

By what definition of continuous? One may chose to ignore its
discontinuity, but that does not make it continuous.

, it just is horizontal from the left, vertical at the
> origin

But how is function which takes the value 0 at 0 and the value 1 at
every positive real argument and -1 at every negative real argument
satisfy the INTERMEDIATE VALUE theorem on any interval containing 0 as
an interior point? or even the mean value theorem?

(the INTERMEDIATE VALUE theorem says that a function continuous on any
interval [a,b] must assume every value between f(a) and f(b) at some
point of that interval)

> No, these are considerations of the plain mathematical universe shared
> among us, using standard definitions and working toward conciliation
> of intuition and rigor, thank you.

But Ross' mathematical universe does not use, much less conform to,
standard definitions, or even allow them, and he opposes anything
resembling rigor.
--

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
11/25/12 ross.finlayson@gmail.com
11/25/12 Virgil
11/25/12 ross.finlayson@gmail.com
11/26/12 Virgil
11/26/12 ross.finlayson@gmail.com
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11/26/12 Virgil
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11/28/12 Virgil
11/29/12 ross.finlayson@gmail.com
11/29/12 Virgil
11/29/12 ross.finlayson@gmail.com
11/30/12 Virgil
11/30/12 FredJeffries@gmail.com
11/30/12 ross.finlayson@gmail.com
11/30/12 FredJeffries@gmail.com
11/30/12 ross.finlayson@gmail.com
12/1/12 Virgil
11/30/12 ross.finlayson@gmail.com
12/1/12 Virgil
12/1/12 ross.finlayson@gmail.com
12/1/12 Virgil
12/1/12 FredJeffries@gmail.com
12/1/12 ross.finlayson@gmail.com
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12/4/12 Virgil
12/5/12 ross.finlayson@gmail.com
12/5/12 Virgil
11/30/12 Virgil
11/25/12 Graham Cooper
11/25/12 Virgil
11/25/12 ross.finlayson@gmail.com
11/25/12 Virgil