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A point's distance?

  1. Jun 30, 2007 #1
    people discuss only distances between points but why not within a point itself ?
    i think a point also has a distance, and the distance becomes zero just under some condition, which can be thought in the same way as when two opposite forces are canceled out in normal simple physical phenomena ?

    you sure hear of the story of how to touch the moon with a finger in Budhism, people touch it by heart.

    what do you think ? thanks a lot
  2. jcsd
  3. Jun 30, 2007 #2

    matt grime

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    I think you're using lots of flowery words to attempt to say what is just true for plain mathematics, has nothing to do with forces cancelling, buddhism, or touching the moon. The distance between two real numbers is denoted |x-y|, and is called the absolute difference. It is 0 if x=y, since it is x-y, if x=>y, or y-x if x<=y.

    I'm not entirely sure how to make sense of the notion 'a point has a distance'. It's like saying a table has a cat.
  4. Jun 30, 2007 #3


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    Perhaps you should explain why you think "a point also has a distance". It might help if you told us what your definition of "distance" is.
  5. Jun 30, 2007 #4


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    A 2D point is just a pair of numbers. Distance is only defined between points so how could one point have distance?
  6. Jun 30, 2007 #5


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    Well, when magnifying a point, you'll still get a point. It's not bigger, it's just it. It's not like a circle. (i.e when you magnify a circle, it becomes bigger). So, a point does not have a distance.
  7. Jun 30, 2007 #6
    for example,

    i buy myself a new t-shirt at $100


  8. Jun 30, 2007 #7
    What's your point? :P Sorry. I don't understand what exactly you're trying to say...

    Points are defined to have no width...they have no dimension.
  9. Jun 30, 2007 #8
    doesn't this belong in the crackpot section or something?
  10. Jun 30, 2007 #9
    Umm... What?
  11. Jun 30, 2007 #10


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    I did not know distance was measured in dollars!
  12. Jul 1, 2007 #11
    In pure mathematics, a point merely has no width or length of itself. That kind of concept may work in engineerings or things similar.
  13. Jul 1, 2007 #12


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    I don't understand why such threads aren't locked.
  14. Jul 1, 2007 #13


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    Then you got ripped off on that shirt, but I still don't see how that has anything to do with a point having distance. :p
    Last edited: Jul 1, 2007
  15. Jul 1, 2007 #14


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    Because it's just too much fun!

    Actually, I was hoping that the OP would answer my questions and explain why he had said that. Since he hasn't bothered to respond, I'm locking this thread.
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