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You might be interested in Kip Thorne (of Gravitation fame) and Roger Blandford's book Modern Classical Physics, which is designed to cover the elements of non-quantum physics that are generally ignored in the first year PhD curriculum. Part headers: statistical physics; optics; elasticity; fluid dynamics; plasma physics; general relativity

I second the recommendation of this book -- it really is quite excellent and covers at an advanced level most of what is commonly left out of a modern physics curriculum (though it is quite imposing in its size/weight).

Fluid dynamics was the most awful course I ever took. I still get nightmares of me failing my graduation because of Navier-Stocks equation

Are you sure you learned the correct equation, Navier-Stokes?

Idiot who transferred from physics to computer science after year 1 here, so please make allowances. But all of those phenomena are emergent. Shouldn’t physics focus much more on the underlying micro states and micro processes than the emergent phenomena?

Obviously there needs to be a transition, but at some point you go from physics to engineering. I suppose it depends what specialty in physics you go into. Nobody can specialise in everything.

Physics: research, theorize

Engineering: practical implementation

That’s how it goes in my brain. It’s physics until we can build it reliably, then it’s engineering.

As GP said, continuum mechanics is often used for physics research. While not the Truth, the models can often be accurate. My own research involving transport in the quantum domain utilized some models from continuum mechanics.

(I didn't introduce it - it was already being used).

You could say that about a lot of topics. Heck you could say that chemistry is just an emergent phenomenon of physics.

The benefit of taking such a class or reading such a textbook is that these things have been studied extensively, we have good models for them, and it is useful to know because people are still doing fundamental research on it to this day or working on phenomena that are closely related.

Reminds me of a student sketch from my days in nerd school, parodying Star Trek. A student dressed as one of the physics professors demonstrated that FTL travel was impossible, causing the Enterprise’s warp drives to stop functioning. It was fixed when Scotty said, “Wait, I’m an engineer: I don’t need to understand physics!”

> Shouldn’t physics focus much more on the underlying micro states and micro processes than the emergent phenomena? Obviously there needs to be a transition, but at some point you go from physics to engineering.

1. The boundaries between disciplines are where they are in part by historical accident, and in part because that's what the people working in them find useful - there is no actual fact of the matter.

2. We don't actually know the underlying microprocesses of anything. Effective theories are all we have, and there's no fundamental difference between an effective theory for the vacuum (if it is a vacuum) and one for, say, the bulk of a semiconductor.

> there is no actual fact of the matter.

This is true of all categories, so not a helpful comment. I suspect someone has a good enough definition.

I think solid state continuum mechanics are also the optimal place to introduce tensors. For some reason, the first tensors many physics students encounter are very abstract. It would be like if the first vectors you encountered were quantum mechanical states. Stress and strain are, in my opinion, the ideal "prototypical rank-2 tensors", and it's useful to spend time really elaborating what that means, the same way we teach students to think of vectors as "things that look like displacement/velocity".

That’s an interesting idea. The best class involving tensors I ever took was an introductory course on differential geometry, and I still think the coordinate-free approach of thinking of tensors as multilinear functions from some number of vectors to some other number of vectors (or a scalar) is great. Everything else just involves picking coordinates and figuring out where the numbers to :)

But I probably like abstractions like this more than most people.

Oddly, undergraduate physics also seems to be missing another, arguably even more fundamental, tensor: the moment of inertia. You can get quite far (in three dimensions, and only in three dimensions) by thinking of rotation as a vector. (Or a quaternion if that floats your boat.) But you can’t get very far by pretending that the moment of inertia is a scalar, and you get very confused very quickly if you treat it as three scalars in the magical coordinate system in which you can write it like that.

Hydraulics are everywhere. Ever used a sink? Flushed a toilet? Contemplated an air filter? Felt both sides of a small fan? Wondered how, exactly, a utility pump causes water to go in the inlet and out the outlet, and tried to read the manufacturer’s spec? Contemplated that the ripples when you throw a rock in an actual pond really don’t resemble the average “look I made water in WebGL” animation very much?

if you can understand the PDEs of GR and QFT, you can apply it to this too

I noticed that too, and my explanation was that physics education needs to set itself apart from engineering.

Classical ( non relativistic ) field theories by now are undergrad engineering topics, but there are only a few quantum engineers.

Most of the non quantum topics in modern undergrad physics curricula, is needed to make sense of quantum[ thermodynamics, filed theory, optics, something ]

Do you have text/other sources suggestions for this? I agree with you, would like to learn more.

Halliday & Resnick Fundamentals of Physics is what we used in AP as well as in freshman year at college. Covers most sections one needs to be familiar with to be physics literate (solid/fluid mechanics, waves, thermo, electromagnetism, optics, relativity).

Is that still in print? That was the physics book we used my freshman year, in 1974. It was a great book. I’m still sorry I sold it.

That was my first year text book in 1998. Sounds like it's still going strong!

Still used in as an undergraduate in 2013

Jearl Walker (of Cleveland State and PBS’s Kinetic Carnival) was added as an author.

I don’t know much about continuum mechanics (unless you count stat mech but I wouldn’t), however Goldstein has a few chapters on the topic that might serve as an introduction

The best book I came across is this https://www.amazon.com/Continuum-Mechanics-Foundations-Appli... It has a slightly solid mechanics bent, but the fundamentals are the same for fluids and solids (conservation laws, tensor formulation)

For the mathematically inclined, the best I've seen is An Introduction to Continuum Mechanics by Morton Gurtin from 1981. At one point, it could be purchased from Google books directly as a pdf.

You've described the core of a usual Chemical Engineering curriculum. A school with a good engineering program would definitely offer these classes, maybe under a name like "transport phenomena" (in my experience).

The undergraduate Physics program is, in my opinion, heavily influenced by the working physicists in the field. Lots of physicist who work in fundamental physics is either particle physicists or work with models that are in particles. Those are the ones who teach physics in undergrad.

This is simply not true, condensed matter physics makes up the largest sub-field of physics (about half by some estimates).

I think the more relevant aspect is that to reach the frontier in a wide array of fields you a solid grounding quantum physics (and several other "new" -- i.e. within the last century or so -- topics) that have displaced more "old-fashioned" topics like continuum mechanics.

Introduction to the Physics of Fluids and Solids by James Trefil might be interesting for you.