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

 Messages: [ Previous | Next ]
 netzweltler Posts: 473 From: Germany Registered: 8/6/10
Re: Cardinality of turning wheel
Posted: Mar 4, 2013 2:00 AM

On 4 Mrz., 05:24, quasi <qu...@null.set> wrote:
> Frederick Williams wrote:
> >quasi wrote:
> >> netzweltler wrote:
>
> >> >Meaning, that the notion of infinite speed is nonsense,
> >> >right?

>
> >> Well, I surely don't know how to make sense of it (but
> >> I'm willing to be educated).

>
> >Would it do to say that if a material object moved a non-zero
> >distance instantaneously, then it moved with infinite speed?

>
> So let's say a particle starts at x=0 on the x-axis and moves
> at infinite speed to the right, arriving "instantaneously" at
> x=1. But then it also arrives at x=2 just as instantaneously.
> In fact, it arrives at every positive x-value in the same
> instant. So what is the position of the particle at time t=0?
> And where is the particle at time t=1?

At finite speeds x=0, x=1, and x=2 are adjacent, at infinite speed
these points are coincident.

> It seems to me that the concept of infinite speed violates the
> intuitive notion of time and space -- that is, it goes against
> the notion that any given particle at a given time has one and
> only location in space. I think that intuitive notion is so
> compelling that it should not be abandoned so casually.

You think transfinite mathematics is intuitive?

> Thus, I would forget about infinite speed unless I could be
> convinced that the advantages of having such a concept outweigh
> the blatant disadvantage of losing our intuitive notions
> (essentially axiomatic notions) about time and space.
>
> quasi

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