Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Mathematically Precise Definition of Unit

  1. Feb 20, 2012 #1
    Does anyone know exactly what kind of mathematical object a unit (like meters, coulombs, etc.) is? Or what kind of algebraic structure units are elements of?
     
  2. jcsd
  3. Feb 20, 2012 #2

    pwsnafu

    User Avatar
    Science Advisor

    Units of measurement is not a mathematical quantity. We use them to calibrate our experiments. I guess you could try to create a structure for them.

    "2 candlesticks" times "3 cabdrivers" = 6 [candlestick][cabdriver].

    That has the same structure as

    (2x) (3y) = 6xy,

    and we can add and subtract if the units are the same: 3 cadlesticks + 2 candlesticks = 5 candlesticks is the same thing 3x+2x = 5x.

    So polynomials. You could let "l" be length and then metre would be "lm" and inch would be "li" and define li = 0.0254 lm.

    Edit: I hate the fact they spell it "meter" in the US. :grumpy:
     
    Last edited: Feb 20, 2012
  4. Feb 20, 2012 #3

    Stephen Tashi

    User Avatar
    Science Advisor

    "Dimensional Analysis" is a branch of applied mathematics (or is it properly called physics?). It is based on the idea that the units in equations that describe physical laws must work out properly, but I don't know if it gives a formal definition of such units.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Mathematically Precise Definition of Unit
  1. Inverses for units (Replies: 1)

Loading...