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Confusion created by notation in E&M

  1. Sep 8, 2012 #1
    I just started an E&M class and right from the beginning the notation seems so confusing it has to have been done as a joke.
    Trying to do a problem I run into about 10 different r's I have to keep track of.
    Capital R
    Lower case r
    Lower case r prime
    The r in spherical coordinates
    The "squiggle" r (As this professor calls it. Never heard that before this class, but he talked about it like everyone knows. It's just a cursive r from what I can tell.)
    "Squiggle" r hat
    Normal r hat prime
    "Squiggle" r with an arrow over it.
    The normal r with an arrow over it
    Normal r with an arrow over it prime

    So when I see an equation with 3 or 4 different r's in it, my head just explodes. Why is it like this? And am I the only one who thinks this makes it confusing?
  2. jcsd
  3. Sep 8, 2012 #2
    This is what happens when you restrict yourself to the latin Alphabet. Try using Greek and Cyrillic letters if you run out.
  4. Sep 9, 2012 #3
    There is a weird fascination with symmetry and making letters look the same. Euler angles were introduced to me with [tex]\xi, \zeta, \eta[/tex] as indices. Integration by parts uses u and v, there is p and q for Lagrange mechanics. i and j for electrodynamics. {j,k,l} and {x,y,z} might not be so bad, but j and l are close in some handwriting as well as x and y. These things will never be reformed because we are still citing papers from 1910. The worst we had was in the discussion of collisions where I think r-prime-prime-tilda-hat was the vector of the second particle after the collision in center of mass coordinates.
  5. Sep 11, 2012 #4
    I find it works extremely well when dealing with an unfamiliar notion to relabel each variable to something that makes sense to you, like [itex]m_{electron}[/itex] instead of [itex]Z_0[/itex] for example. Then rewrite all of the equations and work with them until you feel comfortable and translate back as required.
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