Is Movement Truly Possible Despite the Paradox?

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    Movement Paradox
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Discussion Overview

The discussion centers around the paradox of movement, particularly referencing Zeno's paradoxes, which suggest that movement is impossible due to the infinite divisibility of distance. Participants explore the implications of this paradox and potential resolutions, focusing on theoretical and conceptual aspects.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Mathematical reasoning

Main Points Raised

  • One participant expresses confusion about how movement could be possible despite the paradox, suggesting it seems very plausible.
  • Another participant identifies Zeno's paradoxes, specifically mentioning the arrow paradox, which posits that an arrow cannot reach its goal if it is always at rest at each moment in time.
  • A participant argues that the paradox assumes infinite divisibility of distance, which may not hold true due to the existence of a smallest measurable distance, such as the Planck length.
  • One participant presents a mathematical argument showing that while distances can be divided infinitely, the time taken to traverse these distances can converge to a finite value, allowing for movement to occur in finite time.
  • Another participant questions whether the conclusion drawn is that movement is impossible, pointing out that the previous argument stated that movement is indeed possible.
  • A later reply references external sources that discuss proposed solutions to Zeno's paradoxes, emphasizing that time is not necessarily divided into discrete steps.

Areas of Agreement / Disagreement

Participants do not reach a consensus on whether movement is possible or impossible, with some arguing for the possibility of movement and others suggesting that the paradox presents significant challenges to this notion.

Contextual Notes

The discussion involves assumptions about the nature of distance and time, as well as the mathematical treatment of infinite series. There is an unresolved debate regarding the implications of Zeno's paradoxes on the concept of movement.

ghostman97
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i'm trying to conclude on HOW this would be possible... though its a paradox doesn't it seem very possible?

in case you don't know what it is its saying movement is immpossible. Example to get from point a to point b you have to go halfway but before you get from point A to A1/2 you have to get halfway there and so on
 
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Hi ghostman97! :smile:

Which paradox are you referring to? Zeno has formulated 3 paradoxes (and maybe more).

  • Achilles can never catch the turtle.
  • An arrow can never reach his goal.
  • How can an arrow move if it's standing still at each instance.
 
basically an arrow can never reach his goal
 
Hmm, let's see if I can explain this nicely. I'm usually quite bad at such things.

Firstly, the paradox assumes that we can keep dividing the remaining distance. But this is not possible since there is a smallest distance: the Planck length. (but you might want an actual physicist to explain this correct/better).

But let's say that we could keep on dividing, how could the paradox fail? Well, the thing is that the time required to walk all these distance decreases exponentially. When we walk the first part, we might take 1 second, when we walk the second part, we take 0.5 seconds. When we walk the third part we take 0.25 second. In total, it would take us

[tex]\sum_{n=0}^{+\infty}{\frac{1}{2^n}s}=2s[/tex]

the thing is that this sum converges and thus the number of second to walk the entire distance is finite. So we can complete an infinity of distances in a finite time!

However, if the paradox says: "walk the first distance, then wait for 1s. Walk the second distance, then wait for 1s. Walk the third distance, then wait for 1s..." Then this is indeed not possible to perform, as it would take an infinite amount of time to do so.
 
so what your concluding is that movement would be "impossible"
 
micromass said:
So we can complete an infinity of distances in a finite time!

ghostman97 said:
so what your concluding is that movement would be "impossible"

Have you actually read micromass answer before responding? He clearly stated: "we can". Thats opposite of "impossible".
 

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