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The search for constancy

  1. Oct 12, 2003 #1
    The search for constancy

    Indeed human nature requires us to search for consistency and constancy.

    However in mother nature as with human nature we see little constancy and even less of consistency.

    Is it possible that we are trying to prove constancy where in fact there is none?

    If I knew mathematics and physics as intimately as you guys, my first action would be to allow inconsistency to exist as an inherent variable.

    Does this already exist in mathematics?

    For example

    One litre of water weighs how much?

    The answer depends on so many variables, from local gravity to ambient temperature, minerals in the water, even the moon’s position would have an effect, etc etc.

    So to say that a litre of water weighs “X” amount with out allowing for unknown variables would be a mistake.

    I feel this approach needs to be applied especially to the study of the very small where variations in constancy would have the greatest effect.

    How do you guys feel about this?
  2. jcsd
  3. Oct 12, 2003 #2


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    Staff Emeritus
    Science Advisor
    Gold Member

    Whenever we talk about any property that can vary with local conditions, The practice is to use "standard" conditions.

    For instance, 1 liter of water weighs 9.81274 Newtons at one standardg.

    Water boils at 100°c at standard at 1 standard atmosphere.

    Hydrogen gas has a listed density at standard temp and pressure (STP)


    So physics already has this well in hand.
  4. Oct 12, 2003 #3


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    Staff: Mentor

    In addition to standards we also use significant digits. So if we say something weighs (for example) 1.00 newtons, that does not mean it is exactly 1 newton, it means its 1 newton plus or minus .01 newtons.
  5. Oct 13, 2003 #4
    hey Russ and others thanks.

    I have realised my mistake in my approach to discussions.

    I tend to always refer to physics in absolute terms.

    it is exact or it aint sort of thing. My studies require this of me but this is no excuse for a failure to communicate properly.

    thanks again
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