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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 5, 2013 2:45 PM

On 2 Mrz., 20:39, quasi <qu...@null.set> 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.
>
> quasi

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

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