1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Maxwell's Equations

  1. Apr 16, 2009 #1
    Could someone point me in the direction of the derviation of each of Maxwell's equations? I'm working on a presentation and can't find a good one that starts with primitive assumptions (i.e. to help explain to a non physics audience).
  2. jcsd
  3. Apr 16, 2009 #2


    User Avatar

    Staff: Mentor

    As far as I know, in classical electrodynamics, Maxwell's equations are ultimately "derived" from experimental evidence, not from more fundamental assumptions. Gauss's Law comes from studies of electric forces by Coulomb and others. Faraday's Law comes from experiments on magnetic induction, most notably by Faraday himself.

    The one exception would be the part of Ampere's Law that was added by Maxwell in order to make the complete set of equations mathematically consistent (the "displacement current" term).

    In modern quantum theory, one can derive electrodynamics (including Maxwell's equations) by requiring that the theory be invariant under local U(1) gauge transformations of the particle fields. See for example the last section of


    I wouldn't want to try to explain this to a lay audience though. :bugeye:
    Last edited: Apr 16, 2009
  4. Apr 16, 2009 #3


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    Try a search at Amer J Phys, which frequently focuses on pedagogical aspects and interesting derivations. There have been several articles on deriving Maxwell's equations over the years.
  5. Apr 16, 2009 #4


    User Avatar
    Science Advisor

    Maxwell's equations are usually considered the most fundamental equations of classical electromagnetism, and therefore cannot be derived. They are accepted because they successfully predict the widest range of classical electromagnetic phenomena. However, if you there is a slightly different approach where you can start with electrostatics, and assume special relativity, and then you are force to invent magnetism, or something like that. I don't remember the details, and I don't know how fudge free this approach is, but you can look at Ohanian's EM text for details.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: Maxwell's Equations