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Topic: Cardinality of turning wheel
Replies: 43   Last Post: Mar 10, 2013 1:55 AM

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 netzweltler Posts: 376 From: Germany Registered: 8/6/10
Re: Cardinality of turning wheel
Posted: Mar 6, 2013 3:37 PM

On 5 Mrz., 22:19, quasi <qu...@null.set> wrote:
> netzweltler wrote:
> >quasi wrote:
> >> netzweltler wrote:
> >> >What is the cardinality of the number of revolutions of a
> >> >turning wheel, if there is no beginning and no end to it?

>
> >> For a wheel revolving forever (both past and future), the
> >> set of revolutions is in one-to-one correspondence with the
> >> set of integers, hence has cardinality aleph-0.

>
> >Is it true to say, that the wheel finishes countably
> >infinitely many revolutions, whenever we assign an origin (the
> >point between past and future)?

[snip]

> As far as the notion of infinite speed, I see the
> specification of such model as problematic, but as I said, I
> would be willing to look at a proposal for such a model, so
> long as the assumptions were fully specified, and sufficient
> justification for analyzing the model was provided.
>
> quasi

Is the notion of infinite speed more problematic to you than the
notion, that any revolution of the countably infinite set of
revolutions can be the origin - revolution #1?

Date Subject Author
3/2/13 netzweltler
3/2/13 Frederick Williams
3/2/13 quasi
3/2/13 netzweltler
3/2/13 William Elliot
3/3/13 quasi
3/3/13 netzweltler
3/3/13 quasi
3/3/13 netzweltler
3/3/13 quasi
3/3/13 netzweltler
3/3/13 Brian Chandler
3/4/13 netzweltler
3/3/13 quasi
3/3/13 Frederick Williams
3/3/13 quasi
3/4/13 netzweltler
3/4/13 quasi
3/4/13 Shmuel (Seymour J.) Metz
3/5/13 Frederick Williams
3/5/13 netzweltler
3/5/13 quasi
3/6/13 netzweltler
3/6/13 quasi
3/7/13 netzweltler
3/7/13 quasi
3/8/13 netzweltler
3/8/13 quasi
3/8/13 netzweltler
3/8/13 quasi
3/8/13 Frederick Williams
3/2/13 Frederick Williams
3/3/13 Frederick Williams
3/5/13 K_h
3/7/13 Frederick Williams
3/7/13 Frederick Williams
3/3/13 Shmuel (Seymour J.) Metz
3/7/13 Frederick Williams
3/10/13 Shmuel (Seymour J.) Metz