5 ms·

In fact, it isn't so hard that they would like you to believe - it just seems that way when they remove the best parts due to national security :D You would ha

In fact, it isn't so hard that they would like you to believe - it just seems that way when they remove the best parts due to national security :D You would have to go back to James Clerk Maxwell's original 20 equations to see what it's all about. Okey, quaternions are kind of hard, I'll admit to that, but all in all it makes much more sense.

pjc50 10y ago
Like QM, doing it analytically clears away misconceptions and gives a consistent view - but it isn't exactly something you can teach to children. It's useful to be able to explain things to laypeople and the not mathematically inclined, which means tightening up the metaphors.
- tim333 10y ago
  Also Maxwell's equations only give you part of it - for the question of why an atom's electrons don't just fall into the nucleus you need QM. And then you get into the self energy of the electron which is not explained by any present physics (http://www.feynmanlectures.caltech.edu/II_28.html http://www.feynmanlectures.caltech.edu/II_28.html). So you can't just do the math because we don't have all the math.
  - johncolanduoni 10y ago
    For electrical phenomena (baring very very small scale, semiconductors) Maxwell's equations give you a huge amount of insight, especially the macroscopic variant. You can see things like plasmons and polaritons (though obviously not their quantization). You won't really run into the atom stuff until you try to do something like calculate dielectric constants analytically, though self-energy is definitely a pretty easy trap to fall in even for macroscopic stuff.
- bronlund 10y ago
  You have a good point, but still, it's easier to explain to children stuff that makes sense. I teach my children that we live in a sea of energy and that you can feel it when you move. It makes much more sense to them than trying explain inertia. I tell them that of you rotate something, it will make an energy vortex making stuff seem heavier - and I show them with a gyroscope. Then I explain that electrons are just like little gyroscopes, but of only energy. And it all makes sense to them. They don't think it's hard at all.
  - pjc50 10y ago
    Those are excellent metaphors which I've never heard anywhere else.
    - matthewmcg 10y ago
      They're reminiscent of Feynman's anecdote about his father explaining inertia: https://www.youtube.com/watch?v=Zjm8JeDKvdc https://www.youtube.com/watch?v=Zjm8JeDKvdc
      - phee 10y ago
        "That - he said - nobody knows". It's kind of different from "we live in a sea of energy". I honestly think inertia is a lot easier to grasp than energy. It's a phenomenon you can experiment, describe and name, energy is more abstract.
    - deleted 10y ago
      [deleted]
  - JoeAltmaier 10y ago
    Hm. Children can learn the right terminology for things. Those words don't seem any easier to swallow than 'inertia' and 'charge' to me.
- lisivka 10y ago
  Can you explain results of double slit experiment (when single particle creates interference pattern) to us, mere mortals, please?
fzzzy 10y ago
I often think about how Maxwell's equations were simplified because quaternions were hard to deal with by hand. Heaviside reformulated them into calculus, which was easier work with and accurate enough for pretty much everything. But now that we have computers, which can trivially deal with quaternions, (probably even more easily than calculus) why don't we go back to using those formulae?
bsder 10y ago
> You would have to go back to James Clerk Maxwell's original 20 equations to see what it's all about. Okey, quaternions are kind of hard, I'll admit to that, but all in all it makes much more sense. Not ... really. The problem is that we teach electromagnetics using a 19th century pedagogy that assumes the existence of the Ether. This works well for some things and makes them nicely closed form and simple. Of course, it breaks down for other things (motors are one of the big ones) where you really want a field description. Of course, a field description makes nothing simple and closed form. So, it isn't good for making exams out of. If you can deal with 4-vectors, "Collective Electrodynamics" is a really good book.
- wbeaty 10y ago
  Carver Mead! He's one of us, ONE OF US (physics crackpots, like JG Cramer here at UW.)

pjc50 10y ago

Like QM, doing it analytically clears away misconceptions and gives a consistent view - but it isn't exactly something you can teach to children. It's useful to be able to explain things to laypeople and the not mathematically inclined, which means tightening up the metaphors.

tim333 10y ago
Also Maxwell's equations only give you part of it - for the question of why an atom's electrons don't just fall into the nucleus you need QM. And then you get into the self energy of the electron which is not explained by any present physics (http://www.feynmanlectures.caltech.edu/II_28.html http://www.feynmanlectures.caltech.edu/II_28.html). So you can't just do the math because we don't have all the math.
- johncolanduoni 10y ago
  For electrical phenomena (baring very very small scale, semiconductors) Maxwell's equations give you a huge amount of insight, especially the macroscopic variant. You can see things like plasmons and polaritons (though obviously not their quantization). You won't really run into the atom stuff until you try to do something like calculate dielectric constants analytically, though self-energy is definitely a pretty easy trap to fall in even for macroscopic stuff.
bronlund 10y ago
You have a good point, but still, it's easier to explain to children stuff that makes sense. I teach my children that we live in a sea of energy and that you can feel it when you move. It makes much more sense to them than trying explain inertia. I tell them that of you rotate something, it will make an energy vortex making stuff seem heavier - and I show them with a gyroscope. Then I explain that electrons are just like little gyroscopes, but of only energy. And it all makes sense to them. They don't think it's hard at all.
- pjc50 10y ago
  Those are excellent metaphors which I've never heard anywhere else.
  - matthewmcg 10y ago
    They're reminiscent of Feynman's anecdote about his father explaining inertia: https://www.youtube.com/watch?v=Zjm8JeDKvdc https://www.youtube.com/watch?v=Zjm8JeDKvdc
    - phee 10y ago
      "That - he said - nobody knows". It's kind of different from "we live in a sea of energy". I honestly think inertia is a lot easier to grasp than energy. It's a phenomenon you can experiment, describe and name, energy is more abstract.
  - deleted 10y ago
    [deleted]
- JoeAltmaier 10y ago
  Hm. Children can learn the right terminology for things. Those words don't seem any easier to swallow than 'inertia' and 'charge' to me.
lisivka 10y ago
Can you explain results of double slit experiment (when single particle creates interference pattern) to us, mere mortals, please?

fzzzy 10y ago

I often think about how Maxwell's equations were simplified because quaternions were hard to deal with by hand. Heaviside reformulated them into calculus, which was easier work with and accurate enough for pretty much everything. But now that we have computers, which can trivially deal with quaternions, (probably even more easily than calculus) why don't we go back to using those formulae?

bsder 10y ago

> You would have to go back to James Clerk Maxwell's original 20 equations to see what it's all about. Okey, quaternions are kind of hard, I'll admit to that, but all in all it makes much more sense. Not ... really. The problem is that we teach electromagnetics using a 19th century pedagogy that assumes the existence of the Ether. This works well for some things and makes them nicely closed form and simple. Of course, it breaks down for other things (motors are one of the big ones) where you really want a field description. Of course, a field description makes nothing simple and closed form. So, it isn't good for making exams out of. If you can deal with 4-vectors, "Collective Electrodynamics" is a really good book.

wbeaty 10y ago
Carver Mead! He's one of us, ONE OF US (physics crackpots, like JG Cramer here at UW.)