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Does point really exist?a mathematical concep

  1. Mar 14, 2014 #1
    does point really exist in reality or it is mere a mathematical concep
  2. jcsd
  3. Mar 14, 2014 #2


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    The word "point", as used in mathematics, is a mathematical concept. That is true of any word used in mathematics. If the mathematics is a from a physical problem, then the word "point" may refer to a mathematical idealization of a real object.

    Of course, the word "point" can be used in non-mathematical ways ("The first point of land we see will be ...", "is there some point to this discussion") in which the "point" may "exist in reality".
  4. Mar 15, 2014 #3
    It is just a mathematical concept, like numbers. It is abstract. You may ask yourself questions like: "what is the size of a point ?" If it has no size, then it must be nothing. But in mathematics we measure sizes using measures, like The Lebesgue measure. The Lebesgue measure of a point is 0. But there's even uncountable sets with measure zero.

    In reality, things are very different and more weird, because if you want to measure a very tiny tiny particle, it will not be there before you measure it. If I told you to point your pen in the real axis to indicate the position of the value 1.4, you will just give me a region with the size of the head of the pen. But when you go smaller and smaller, you suddenly enters a world where space has no sense, even time is not defined (see the delayed choice quantum eraser experiment). So even the word "reality" you used in your comment makes no sense in this scale.

    Even if this approach of giving an object a place using a point doesn't work in tiny scales, Mathematics seem to always give beautiful formulations of even weird things like quantum physics.
    Last edited: Mar 15, 2014
  5. Mar 15, 2014 #4

    Stephen Tashi

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    "Reality" doesn't exist as a mathematical concept - at least not as a concept that is well known enough to have a standardized definition. Mathematics itself doesn't answer the question about whether something exists "in reality".

    Perhaps you mean "reality" in the sense that the word is used in Philosophy or Physics. The forum has rules against discussing Philosophy (I've never understood the scope of these restrictions, perhaps you can talk about it in "General Discussions") If you can formulate your question so it is concrete and specific, you might be able to get an answer in the Physics sections.
  6. Mar 15, 2014 #5


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    Leave "reality" to the Philosophers. It's not a useful concept in physics either. Physics is about what is observed, not about what "really" causes what we observe.
  7. Mar 15, 2014 #6
    That seems ironic considering the entire point of physics is to find mathematics and explanations that accurately conform to the evidence of "reality" based on specified parameters, which can then be applied as a general rule. Why would physicists be looking for a theory of everything if they were not interested in finding out what really causes what we observe?
  8. Mar 15, 2014 #7
    Good replies everybody! It seems like a good place to end the thread.
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