Looking for a textbook that uses the electromagnetic wave view of electric current

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Discussion Overview

The discussion centers on the conceptual understanding of electric current, particularly the view that energy is propagated as electromagnetic waves rather than the traditional notion of electron flow. Participants explore the implications of this perspective and seek textbook recommendations that align with this view, covering theoretical and practical aspects of electromagnetism.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants suggest that while the flow of electrons is a practical model, it does not accurately represent the underlying physics, which involves electromagnetic wave propagation.
  • One participant notes that the flow of electrons is slow and carries little energy, with the electric and magnetic fields created by this flow being responsible for energy transport, rather than traditional electromagnetic waves.
  • Another participant mentions that textbooks on transmission lines or open waveguides may provide relevant information on the topic.
  • It is proposed that any textbook on electrodynamics could be useful, although some may still rely on misleading analogies like the "water-pipe analogy" for circuits.
  • A specific recommendation is made for A. Sommerfeld's "Lectures on Theoretical Physics" for discussions on coaxial cables and signal propagation.

Areas of Agreement / Disagreement

Participants express differing views on the accuracy of the electron flow model versus the electromagnetic wave perspective. There is no consensus on a single textbook recommendation, and the discussion remains open with multiple viewpoints presented.

Contextual Notes

Participants acknowledge that the traditional understanding of electric current may be limited and that the discussion involves complex concepts such as near-fields and wave propagation in circuits. Some limitations in understanding may arise from the reliance on specific analogies or the depth of the material covered in suggested textbooks.

DrBanana
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So I watched a couple of videos on Youtube with the titles 'How Electricity Actually Works' and 'The Big Misconception About Electricity' ( and ).

The main message being that while the view of current being the flow of electrons might be useful practically, it's not an accurate representation of what actually happens, and the more accurate description is that the energy is propagated as electromagnetic waves.

I appreciate the clarification but it also brings up a lot of questions, because much of what you learn about related stuff is based on the fact that electrons flow in a significant amount through wires, such as wires heating up, or even the Peltier Effect. So I was looking for a textbook that started with this more accurate view, and gradually built on that.
 
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DrBanana said:
The main message being that while the view of current being the flow of electrons might be useful practically, it's not an accurate representation of what actually happens, and the more accurate description is that the energy is propagated as electromagnetic waves.

I appreciate the clarification but it also brings up a lot of questions, because much of what you learn about related stuff is based on the fact that electrons flow in a significant amount through wires, such as wires heating up, or even the Peltier Effect. So I was looking for a textbook that started with this more accurate view, and gradually built on that.
While I don't have any textbook suggestions, this is a topic that has been discussed previously here on Physics Forums. For example, here is a thread that I participated in:
https://www.physicsforums.com/threads/power-flow-outside-a-wire-how-close.1053463/
Note that, while it's true that "electrons flow in a significant amount through wires", they travel so slowly that they carry very little total energy. Instead, the flow of electrons through the conducting circuit serves to create and direct the electric and magnetic fields outside of the wires, and it is those fields that transport the bulk of the energy. And this transport is not by "electromagnetic waves" in the usual sense of transversally-polarized radiation (e.g., radio waves or microwaves), since those would escape from the circuit and carry energy away to infinity. Instead, at DC or low frequencies like 50-60Hz, the energy is propagated by EM "near-fields", i.e., fields confined to the vicinity of the circuit.
 
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Any textbook on electrodynamics should do (except some didactics textbooks, which still promote the "water-pipe analogy" for circuits, which is completely misleading for the very reasons you discovered on Youtube, though I haven't seen these videos, so I can't judge, how reliable they are).

A very thorough discussion of the most simple exactly solvable case, the "infinitely long" cylindrical coaxial cable for a DC circuit, is in A. Sommerfeld, Lectures on Theoretical physics vol. 3. That's doable at the undergrad level.

For the more interesting case of time-dependent fields, e.g., to answer the question of signal propagation when switching on the circuit or for AC circuits, you need a bit more advanced methods. If you restrict yourself to the most simple "TEM mode" of the coax cable you get the "telegrapher's equation", which is also doable at the advanced undergrad level. The full-fledged wave-guide theory is a bit more advanced. It can also be found in Sommerfeld's books (also in vol. 6 about partial differential equations, which is anyway highly recommended).
 
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