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Is distance an illusion?

  1. May 18, 2015 #1
    I'm not familiar with the format of the forum, but could someone straighten me out on a question about distance and as to whether or not distance is only an illusion? How is it that the human body and the immediate physical world JUST HAPPENS TO BE on a scale of size that is so close to what we consider zero length, when you can look out a universe with apparently no end. That is, a 6 feet tall man is only 6 feet larger than zero length. A man can put his two index fngers together and say "that's zero length", but he can't even fathom the distance to the nearest star. So, is zero length even attainable, after all, it is infinitely small. If a human were the size of the apparent size of an electron ( 2 x 10 -15 meters) then 6 feet distance would be(if may calculations are correct) about 1/4 light year away. So for an electron at our toes, the top of our head would be 1/4 light year away. So the human body is huge compared to an observer on an electron. I think our perspective of the world around us is only a point in space afterall. This is more philosophical than hard science obviously. To summarize, how does the size of a human JUST HAPPEN to be so close to one end of the distance "yardstick" (6 feet from zero) and so seemingly infinitely far from the other end of the distance "yardstick". Is our seeming proximity to zero length only an illusion or are we situated somehere within the scale which goes from the infinitely large to the infinitely small, neither of which are obtainable.
  2. jcsd
  3. May 18, 2015 #2
    Not sure but Zeno ' s paradox may be of interest to you.
  4. May 18, 2015 #3
    Thanks. I did look over this. Distance is probably interpreted in terms of how long it takes to reach the distance. If we had arms that could reach out and grab a nearby galaxy( in addition to scaling up size, you would have to scale up the speed at which you could extend your arm which would exceed the speed of light which I'm not sure is theoretically possible), then I guess that galaxy would not be so far away.
    Last edited: May 18, 2015
  5. May 18, 2015 #4
    6 feet would take light approx. 6 nanoseconds to travel. What's your thinking on why it would take 1/4 l.y.?
  6. May 18, 2015 #5
    If you consider relative distance and velocity: So, a 2 meter tall person running 2 meters per second would be equivalent to a
    2x10^-15 meter "tall" electron "running" 2x10^-15meter/second. So the "speed of light" in the electron's realm would be about
    3x10^-7m/secThat is, the distance of 2.98x10^8 meters(distance light travels in one second) would be to a 2 meter tall human what
    3X10^-7meters would be to a 2X10^-15meter "tall" electron. Kind of a silly concept, and don't want to bore you. Still seems that distance is a relative concept.Thanks for entertaining the question.
    Last edited: May 18, 2015
  7. May 18, 2015 #6
    Sounds like you are simply referring to that it is strange that particles tend to stick together which is not only a property of space but due to the properties of particles, such as their relation to the cause of forces.

    In fact this length is very far from your example of holding two fingers together. The force fields wont even let the molecules come this close: 1 planck length =
    1.61619926 × 10-35 meters.

    Why do we need to reach intermediate positions if everything is just one dot, at the same place? Distance is obviously not an illusion. Perhaps in the case of relativity it is according to how we predict other frames of references.
    Last edited: May 18, 2015
  8. May 18, 2015 #7
    Humans are not at all closer to one end of the scale than the other. We are very close to the middle.
  9. May 18, 2015 #8


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    You are indeed correct. And since this isn't a philosophy forum, thread locked.
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