motion is impossible

[reverse]

If a body moves from A to B then before it reaches B it passes through the mid-point, say B1 of AB. Now to move to B1 it must first reach the mid-point B2 of AB1 . Continue this argument to see that A must move through an infinite number of distances and so cannot move. Zeno of Elea 450 BC

 

?

[swansont]

Yes, that is one of Zeno's paradoxes, known as the dichotomy. Discussions of them can be found using Google, which would yield results like Wikipedia. Did you have a question?

[ed84c]

No, It moves through a mulitple of "Plank Lengths"

 

I forget the exact length, but its either the distance light travels in a plank time, or a plank time is the time it takes light to travel a plank length.

[Johnny5]

No' date=' It moves through a mulitple of "Plank Lengths"

 

I forget the exact length, but its either the distance light travels in a plank time, or a plank time is the time it takes light to travel a plank length.[/quote']

 

Distance travelled is a frame dependent quantity.

 

one Planck length is something around 10^-35 of a meter.

 

But if something jumped that distance in one frame,

 

it would have jumed twice that distance in a frame moving relative to the other frame, at twice the speed.

[Callipygous]

isnt there already a thread on this?

[Dave]

I'm pretty sure there's a couple of threads on it.

[reverse]

Yes, that is one of Zeno's paradoxes, known as the dichotomy. Discussions of them can be found using Google, which would yield results like Wikipedia[/url']. Did you have a question?

 

It seemed like a paradox to me as well.

I was wondering what the calculus would make of it.

[Callipygous]

It seemed like a paradox to me as well.

I was wondering what the calculus would make of it.

 

anyone at the calculus level would realize that the instant you're moving, you are covering an infinite number of distances every second. infinity/infinity is perfectly capable of being a real number. so things can in fact move (obviously).

 

whenever someone tells you movement is impossible i recommend the stapler method.

[□h=-16πT]

[math]\sum ^{\infty}_{n=0}\frac{1}{2}\left( \frac{1}{2} \right) ^n=1[/math]

 

'Tis what the calculus says.

[Ophiolite]

isnt there already a thread on this?

I'm pretty sure I've corrected ed's spelling of Planck before. [ed, if it wasn't you, then 'sorry'. If it was you, 'pay attention'.] It's deja vu all over again.

[reverse]

[Dave]

'Tis what the calculus says.

 

Well, yes. But Zeno was saying that you can only take a finite number of steps, and that summation involves a limit which is never actually attained