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This quote

  1. Dec 15, 2008 #1
    No matter how close you ever think you are, there is always a infinite distance between.

    Why is it wrong?
    Why is it right?

    I have no experience in physics, but I feel you guys could answer better then anyone else.

  2. jcsd
  3. Dec 15, 2008 #2


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    That's Zeno's paradox. It breaks down on the atomic level.
    You get half-way to your girlfriend, then half of that distance, then half of the remainder, and so on. So you never actually get there... but you can get close enough for all practical purposes. :biggrin:
  4. Dec 15, 2008 #3

    Ranger Mike

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    two reasons the above girl friend scenario will not apply!

    Dolly Parton !!
  5. Dec 15, 2008 #4


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    Please don't double-post... :uhh:
  6. Dec 15, 2008 #5
    ... I suddenly feel the urge for experimentation ...
  7. Dec 15, 2008 #6
    Yeah, but assuming constant speed, it also takes you half as long to go through each step, so you end up doing an infinite amount of those half-step moves in a finite amount of time.
  8. Dec 15, 2008 #7
    I can stroll across the street because it's about twenty feet distance. That's finite. The idea that we can divide the distance infinitely (at least mathematically) has nothing to do with actually crossing the physical distance because I'm not being divided (or shrunk down) infinitely. The street isn't being divided. Nor is the sidewalk. These dimensions are set and stable.
  9. Dec 15, 2008 #8
    This is one of many recurring topics. Perhaps there should be a FAQ for these, where the solutions and links to resources are given. Then where a moderator sees that, the OP can be directed there followed by a lock.
  10. Dec 15, 2008 #9


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    As this is stated, it is clearly not true. If I am 3 metres, say, from my destination, there is certainly not an infinite distance between us.
  11. Dec 15, 2008 #10


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    Even Zeno's paradox isn't really a big deal if you understand that it defines a mathematical situation that isn't physically real.
  12. Dec 15, 2008 #11
    Or that infinite series can be summed.
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