Classical Confusion between Electrodynamics texts

[Meir Achuz]

Thank you caz for reply!
Yes vector analysis is difficult but I have enough time to learn it. One more thing, should I have to go through the chapters on antennas, transmission lines, waveguides?

Vector analysis cannot be put off. It is required if you want to understand electromagnetism.
The problem is that most texts treat them as separate subjects.
You could try "Classical Electromagnetism" by Franklin which coordinates Vector Analysis with the electromagnetism. It is more advanced than Griffiths, but the first three chapters, which introduce vector anaylsis, are fairly simple.

 

[vanhees71]

Sure, it's nonsense to think you could learn physics without using the only adequate language to discuss it, and that's almost all in terms of analytical/differential geometry.

You get quite a long way with Euclidean vector calculus. In classical mechanics and (in the non-covariant "1+3 formalism" of relativity) electrodynamics you only rarely need 2nd-rank tensors (in point-particle mechanics the tensor of inertia for rigid bodies, in continuum mechanics and electrodynamics the stress/Maxwell stress tensor and, if you cover crystal optics, the dielectric tensor).

For the fully covariant relativistic electrodynamics, which has great advantages concerning consistency and in some sense even implification from a more advanced point of view, you need tensor analysis for the pseudo-Euclidean affine Minkowski manifold. That's not too difficult to learn with some experience in the Euclidean vector calculus formalism.

I'm not so sure, whether it makes sense to use more advanced and modern techniques like the Cartan calculus of differential forms or the coordinate- and frame-independent formulations although they have some calculational advantages compared to the more traditional style using the Ricci calculus, which sometimes tends to be quite an "index battle". I'd think that's not so necessary for the introductory undergraduate topics than rather for advanced topics in General Relativity.

What also seems to be underrepresented in the traditional curriculum is (Lie-)group theory. If there is one unifying concept of all physics it's symmetry principles and thus the extended view on geometry (in the wider sense) introduced by Klein's Erlanger program somewhat earlier than it became the utmost important theoretical tool of modern physics in the 20th century. I think at least some glances on these topics already in the earlier theory lectures (e.g., Poisson brackets and their Lie-algebra structure in the analytica-mechanics lecture) can help greatly to understand the necessarily more abstract quantum mechanics and (relativistic) quantum field theory.

 

[andresB]

I found electrodynamics to be the hardest topic in my undergraduate curriculum.
In my second course on undergraduate intermediate electrodynamics (time-dependent stuff) my professor gave us copies of Sadiku, and I hated it. Probably a bias against EE texts.
Griffiths is good enough for most topics, but if I remember correctly, the treatment of the Lieanrd-Wierchert potentials is utterly confusing. In that regard I was pleasantly surprised by Vanderlinde's book.

By the way, talking about older books (that I have not read), what about Panofsky and Phillips? seems quite interesting.

 

[Vanadium 50]

We are talking about a first book in electromagnetism. You know, what's taught to freshmen and sophomores. Not upper division, and certainly not graduate level.

 

[andresB]

Well, my first course ever on electromagnetism used Alonso & Finn and Feynman lectures. Nowadays I would complement them with "Student's Guide to Maxwell's Equations" by Fleisch.

But it is weird since Griffiths was mentioned. Do people really use and recommend Griffiths for a first book ever on electromagnetism?

 

[Amrator]

Oh for the love of God, can we please stop recommending upper division and graduate books to beginner students on this forum? Griffiths, Schwarz, Franklin, etc. are not suitable for someone who just finished K&K.

OP, just start with Electricity & Magnetism by Purcell supplemented by A Student's Guide to Maxwell's Equations by Fleisch. If you don't like Purcell, then maybe try Fundamentals of Electricity and Magnetism by Arthur Kip.

 

[vanhees71]

I found electrodynamics to be the hardest topic in my undergraduate curriculum.
In my second course on undergraduate intermediate electrodynamics (time-dependent stuff) my professor gave us copies of Sadiku, and I hated it. Probably a bias against EE texts.
Griffiths is good enough for most topics, but if I remember correctly, the treatment of the Lieanrd-Wierchert potentials is utterly confusing. In that regard I was pleasantly surprised by Vanderlinde's book.

By the way, talking about older books (that I have not read), what about Panofsky and Phillips? seems quite interesting.

I find the Lienard-Wiechert potentials really loose their intimitating nature when treating them relativistically. Here's my try to explain them (Sect. 4.5):

https://itp.uni-frankfurt.de/~hees/pf-faq/srt.pdf

 

[dextercioby]

Oh for the love of God, can we please stop recommending upper division and graduate books to beginner students on this forum? Griffiths, Schwarz, Franklin, etc. are not suitable for someone who just finished K&K.

OP, just start with Electricity & Magnetism by Purcell supplemented by A Student's Guide to Maxwell's Equations by Fleisch. If you don't like Purcell, then maybe try Fundamentals of Electricity and Magnetism by Arthur Kip.

You are right about that. We're talking of at least two levels of education:
- beginner in college/university level electromagnetism.
- intermediate/advanced level electromagnetism.

Beginner level > focuses on Maxwell's equations in vacuum and matter, electrostatics, magnetostatics, all treated with vector calculus and multivariable real calculus.
Medium/advanced > defines "electrodynamics", uses special relativity (including Minkowski spacetime notation) and all derivations from it.

People here always focus on the second part and provide recommendations for at least intermediate-level education.

 

[vanhees71]

What's wrong with Griffiths for the "beginner level"? We are focused on the "relativity-first approaches", because inevitably Purcell's Berkeley Physics Course volume is mentioned all the time (for whatever reason ;-)).

BTW: Some professors here in Frankfurt very successfully use a "relativity-first approach" at the "beginner level" (3rd semester undergrad theoretical-physics course lecture). I think in some respects the relativistic formulation is simpler than the 19th century (3+1) formulation. On the other hand for beginner the most difficult part simply is the use of vector calculus, and I don't know whether they can really appreciate the covariant 4D formalism at this stage.

 

[Vanadium 50]

What's wrong with Griffiths for the "beginner level"?

The first line in Griffiths - the very first line - is "This is a textbook on electricity and magnetism, designed for an undergraduate course at the junior or senior level".

If the author doesn't think it's intended for freshmen or sophomores, should we be recommending it?

 

[Amrator]

What's wrong with Griffiths for the "beginner level"? We are focused on the "relativity-first approaches", because inevitably Purcell's Berkeley Physics Course volume is mentioned all the time (for whatever reason ;-)).

BTW: Some professors here in Frankfurt very successfully use a "relativity-first approach" at the "beginner level" (3rd semester undergrad theoretical-physics course lecture). I think in some respects the relativistic formulation is simpler than the 19th century (3+1) formulation. On the other hand for beginner the most difficult part simply is the use of vector calculus, and I don't know whether they can really appreciate the covariant 4D formalism at this stage.

And there's a reason why Purcell is often recommended; it's a pedagogically effective, beginner level (freshman or sophomore level) textbook. Griffiths, while also a great book, is not a beginner level textbook.

 

[dextercioby]

It all, obviously, depends on the curricula of each university and country specifics. In Europe (Germany, for example), in undergraduate (calling "Masters" 2 years of graduate studies which follow for students willing to be physicists) we have three years, covering all fundamental physics courses, from general overview in engineering, or Newtonian mechanics, up to QED and General Relativity. All compacted in 3 years after Bologna EU system. So yeah, there could be that the books meant for teaching in Europe do not apply to same-age students in the US. Most questions here (textbooks subforum) are from students in the US, so we have to know first what syllabus has an electromagnetism course for each year of university studies in the US, in order to be able to recommend appropriate texts.

 

[robphy]

If you just finished Kleppner & Kolenkow, but do not have the prerequisite vector calculus, then you should use an advanced introductory text like

1. Moore - http://www.physics.pomona.edu/sixideas/ Unit E. (Unit R deals with relativity.)
2. Chabay & Sherwood - https://matterandinteractions.org/ (I'm not thrilled with how relativity is handled here... but geometrical and physical intuition and computation (using VPython/Glowscript) for vector calculus is good.)
3. Purcell - Electricity and Magnetism
4. (for mathematically-oriented students): Bamberg & Sternberg's A Course in Mathematics for Students of Physics, vols 1 and 2 ( https://www.amazon.com/dp/0521406498/?tag=pfamazon01-20 )
   

   This book, with apologies for the pretentious title, represents the text of a course we have been teaching at Harvard for the past eight years. The course is aimed at students with an interest in physics who have a good grounding in one-variable calculus. Some prior acquaintance with linear algebra is helpful but not necessary. Most of the students simultaneously take an intensive course in physics and so are able to integrate the material learned here with their physics education. This also is helpful but not necessary. The main topics of the course are the theory and physical application of linear algebra, and of the calculus of several variables, particularly the exterior calculus.

In some places, K&K is a honors-level introductory mechanics text.
Purcell is a common honors-level introductory electromagnetism text,
or an intermediate electromagnetism text.

Moore and Chabay&Sherwood are relatively new introductory calculus-based textbooks that
(in my opinion) try to develop a deeper understanding of concepts than is found in
typical introductory physics texts.

Griffiths is not an introductory electromagnetism textbook.
It assumes a prerequisite given by one of the above texts (or those comparable to them).

 

[vanhees71]

The first line in Griffiths - the very first line - is "This is a textbook on electricity and magnetism, designed for an undergraduate course at the junior or senior level".

If the author doesn't think it's intended for freshmen or sophomores, should we be recommending it?

I'm not familiar with the subtleties of the American curriculum. I always thought Griffiths is one of the standard texts for the introductory theoretical E&M lecture. At least it fits the purpose for the German system very well (of course you can not cover all its contents in 1 introductory semester).

 

[Dr Transport]

Electromagnetics above Halliday and Resnick is not taken until the 3rd or 4th year of undergrad. Introductory electromagnetics is out of Halliday and Resnick or an equivalent text as a freshman, typically the second semester of the freshman sequence.

 

[jtbell]

Electromagnetics above Halliday and Resnick is not taken until the 3rd or 4th year of undergrad. Introductory electromagnetics is out of Halliday and Resnick or an equivalent text as a freshman, typically the second semester of the freshman sequence.

This is the case in the US, except maybe at elite schools like MIT, Caltech, et al.

When do European students usually see physics at the level of H&R? Pre-undergraduate (which we call “high school”)?

 

[andresB]

It was not until I started visiting forums and the like that I noticed how diverse curricula are around the world.
In my south American country, calling Halliday and Resnick pre-undergraduate feel strange. I use H&R (or equivalent books) for first year university physics. Though, first year university here is like final year high school in the US or UK.

 

[vanhees71]

In Germany, we start with a 6-semester BSc degree. In physics there are two main series "experimental physics" and "theoretical physics". Books like Halliday and Resnick or Tipler are textbooks which can well be used in the experimental physics course. You have the standard topics

1st Semester: Mechanics and thermodynamics
2nd Semester: Electromagnetism
3rd Semester: (a) Optics (b) Atoms and Quanta
4th Semester: (a) Nucear and particle physics (b) Solid state physics

In theoretical physics a typical textbook series are the books by Greiner or Nolting

1st Semester: Mathematical methods (mostly with Newtonian mechanics)
2nd Semester: Analytical Mechanics (Lagrange, Hamilton, intro to relativity)
3rd Semester: Electromagnetism
4th Semester: Nonrelativistic quantum mechanics
5th Semester: Statistical physics

In addition you have also Mathematics for Physicists (3 semesters), the introductory and advanced labs (2+1 sem), and some minor subjects you can choose from both experimental and theoretical physics.

In the 6th semester you have to do some research and write a BSc thesis.

Then there's a 2years MSc, consisting of more special lectures in experimental and/or theoretical physics of your choice, some lab work and finally a more advanced research work towards your MSc thesis. At our university you can also choose an MSc with more focus on computational physics, where you get more IT and numerical math and also write your thesis about such topics.

 

[andresB]

1st Semester: Mechanics and thermodynamics
2nd Semester: Electromagnetism
3rd Semester: (a) Optics (b) Atoms and Quanta
4th Semester: (a) Nucear and particle physics (b) Solid state physics

In theoretical physics a typical textbook series are the books by Greiner or Nolting

1st Semester: Mathematical methods (mostly with Newtonian mechanics)
2nd Semester: Analytical Mechanics (Lagrange, Hamilton, intro to relativity)
3rd Semester: Electromagnetism
4th Semester: Nonrelativistic quantum mechanics
5th Semester: Statistical physics

In addition you have also Mathematics for Physicists (3 semesters), the introductory and advanced labs (2+1 sem), and some minor subjects you can choose from both experimental and theoretical physics.

In the 6th semester you have to do some research and write a BSc thesis.

I...have no words, I don't understand many things in that list, how do you condense so much material in 3 years?

For comparison the theoretical component was something like

1. Newtonian mechanics (Alonso & Finn), differential calculus.
2. Oscillations and (linear) waves (French, I think), integral calculus, probability, linear algebra.
3. Electromagnetism (Alonso & Finn II), Vector calculus, (ordinary) differential equations
4. Optics (Hecht), Mechanics (Marion), Complex variables, computational methods.
5. Modern physics (Alonso & Finn 3), Analytical mechanics (Goldstein), Mathematical physics (Arfken), electromagnetic theory I (Griffiths or Mildford) (<==This semester was ridiculous)
6. QM I (Griffiths), electromagnetic theory II (Sadiku, why? I don't know), Mathematical physics II (Arfken)
7. QM II (Cohen-Tannoudji), Thermodynamics, special relativity
8. Statistical physics.
9. Solid state physics.
10. Write your Bcs thesis.

I also took, as electives, particle physics (griffiths) and Intro to general relativity (Weinberg).

I suppose that list would be unfathomable for most people around the world.

 

[vanhees71]

But that looks not different from the German standard curriculum, I quoted above.

 

[andresB]

But that looks not different from the German standard curriculum, I quoted above.

Your curriculum has 6 semesters, ours have 10. Granted, I guess our 1st year in university is like the final year in the US and European high schools, but still.