(Physicist here.) Looked at TOC, then skimmed some chapters. The special relativity part of the book is about as deep and denser than most undergraduate introductions, with less motivations and intuitive discussions. The general relativity part is dense by necessity (after all 95% of it is differential geometry, no way around it), and this book apart from being way more condensed isn’t in any way diluted.

It’s a compact book of essentials for mathematically minded people*. It’s not a shallower-than-textbooks accessible introduction one step up from pop science.

* If you only ever took some linear algebra and calculus for engineering students, this probably doesn’t describe you.

This is fair enough. Hopefully some will still find it useful. I will note that I took a special relativity course in university that did things the "slow and intuitive" way, and many years later realized I still had some fundamental misconceptions about it. Eventually learned it the right way mostly by osmosis. More examples and motivation doesn't necessarily lead to correct understanding.

> Hopefully some will still find it useful.

Yes, I definitely think it will be useful for mathematically minded people who don’t find the “slow and intuitive” approach helpful. However, I suspect the fact that it is posted to HN where most of the audience would be people who only took some math for engineering students and that “popular physics book” is even mentioned on the homepage (it clearly says “unlike”, but for most textbooks this comparison isn’t even needed) might give rise to the misconception that it’s between pop science and other textbooks in terms of depth, as the root of this thread seems to demonstrate.

I recommend Sean Carroll’s “Biggest Ideas in the Universe” series on YouTube for modern physics. He’s a professor at CalTech. Each is 60-90 minutes with an accompanying 60-90 minute Q&A—don’t miss the latter, they’re just as interesting. You won’t get a PhD after watching them but he gets a lot mathier than e.g. a Kurzgesagt video while only assuming a high school education (basic calculus, trig, vectors).

Just read a textbook. It's not easy, but it's what you want:

- rigorous treatment of the material

- no bullshit fluff

- exercises that you can do to think about the material and test your comprehension (often 50-100% of the answers are available online)

- systematic treatment used to train real physicists

In my experience, it's all about the homework. The rest just supports that.

I quite like this lecture series, and I normally hate learning from YouTube videos: https://www.youtube.com/playlist?list=PLFeEvEPtX_0S6vxxiiNPr...

Dr. Schuller’s lectures is one of the few recordings of this kind on YouTube that I can listen to without getting irritated by one thing or another. (Another one being the widely known physics lectures by L. Susskind.)