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Re:Maxwell's Equations first published 150 years ago by jacobolus on Monday November 23, 2015 @08:43PM (#10618633)
And the one we should know is the Geometric Algebra formulation, where it ends up as Maxwell’s Equation, singular.

Gibbs/Heaviside vectors are cumbersome and confusing, and the faster we can dump them as a society the better.

Re:Maxwell's Equations first published 150 years ago by 4ad on Tuesday November 24, 2015 @06:43AM (#10620228)
The vector calculus formulation is not cumbersome and confusing, and we should not replace it. Many problems are simplest in vector calculus. Also, vector calculus formulation gives some insights that are not evident in other formulations. It's also extremely enlightening from a pedagogic perspective when you are learning physics. Of course if you're a mathematician and you don't want to learn physics, than vector calculus is just a distraction because it's idiosyncratic and doesn't connect with anything else.

The differential forms formulation, which in many other cases (but not all!) is more useful to work with than the vector calculus formulation should probably be replaced with geometric algebra though. They are basically the same thing, but differential forms are more idiosyncratic, and some symmetries are not apparent. Neither are useful as an introduction to the aspiring physicist or engineer though.

Re:Maxwell's Equations first published 150 years ago by noselfrighteous on Monday November 23, 2015 @09:14PM (#10618752)
Can you link to an explanation/derivation of the geometric formulation?
Re:Maxwell's Equations first published 150 years ago by iheartmemcache on Tuesday November 24, 2015 @02:45AM (#10619615)
Yep. I'm real glad Hestenes has been championing VA/VC so hard. That first text is a perfect supplementary reading that any undergraduate should read. Who was the author?

I skipped the a few and went straight to the last PDF (the Survey) and coming from a stronger foundational math background, I felt right at home. (I'd imagine those who went down the physics route would be thrown off by the notation though, so I understand the author's preface). He mentions physics and CS applications, but I really think this has structural engineering applications as well -- e.g. R^4 seems like a perfect domain to explore bidirectional tensile and shear strength of materials (especially composite materials/aggregates), then perform some FEA with all of the simple operations within that come inherent to operating within the bounds of the 4-vector form. I mean that's a real trivial example (and I obviously don't know enough about structural engineering to make a good analogy) but it seems like one of those cases where you move the problem set lifted into another domain, perform your manipulation then finally lower back into your original (co-)domain. (Frequently done in algebraic topology, most famously by Perelman on Poincare)

Re:Maxwell's Equations first published 150 years ago by semi-extrinsic on Tuesday November 24, 2015 @04:22AM (#10619877)
I think there is a very good reason why structural engineers never see this type of thing, and it's because most structural engineers don't like math. They like clicking buttons in their CAD/FEA/BIM/<insert-latest-TLA> computer system.

The people who write those systems on the other hand enjoy this math very much, and tend to use Galerkin as a verb and will casually point out just how wonderful the Lax-Milgram theorem is.

Re:Maxwell's Equations first published 150 years ago by sampo on Monday November 23, 2015 @09:44PM (#10618853)