Excellent little book that explains the gist of relativity. Concepts are explained using math a smart high schooler should be able to follow. Lot's better than the one-chapters introductions of relativity you find in Hawkins or Greene

Six not-so-easy introduces 6 topics, each one building on-top of the last, culminating in the final topic of the geometry of spacetime. Discussion includes just enough math as to pass on a real understanding without being overwhelming to someone without much of a background in physics, and to allow you to traverse from the relatively simple initial topic of vector algebra to the advanced final topic of spacetime.

By the end of the book I had learned about the appearance of asymmetry of left and right in living things, how to figure out how much energy is released when an atom splits, and how your clock will run fast if you live higher up. Along with the fun and interesting examples, there is a deep underlying framework of understanding for modern physics.

"Non ridete delle notazioni, inventatene: esse sono potenti."

This isn't as accessible as Six Easy Pieces (perhaps obviously) but it's still solid Feynman lecturing and a great read for anyone interested in the material.

I will give the same review I did with the "Six Easy Pieces", but just different catch. It is for people that want to dive into deeps of physics. Opening your eyes in the glasses of a genius, is an unfound treasure.

more mathy, but still some cool concepts in here, particularly around space-time and the speed of light

A solid continuation of the Six Easy Pieces. Very similar wry and exciting style, but with quite a bit more math and complexity. Still reads easily - you can even just skip the notations, though is Feynman points out lots of progress in physics comes from using better notations. Great book to expand your horizons and question the assumed notions.

Once you reach one piece you want to know more of it which made me research more online on each and learn more all because of this book!

I read the Six Easy Pieces from Feynman two years ago, and after reading Albert Einstein's biography recently, decided to read the Six Not-So-Easy Pieces as well, since it's about Einstein's Theory of Relativity.

The book starts with vectors, transformations, and symmetry of physical laws, and with that foundation, explains the theories and experiments that led up to Einstein's theory. It was interesting to see how much the scientists already knew before Einstein's paper in 1905. Lorentz had already proposed his transformations that explained, in mathematical form, the special relativity, they just didn't know the physical consequences of that.

Later the book explained the relativistic energy and momentum, which was much harder for me to understand in detail, followed by space-time and four vector algebra, and finally the curved space, which is explained so masterfully by Feynman.

Overall a great book, even though as the name suggests, not so easy!

Another great read. A bit more difficult to understand than the 'Six easy pieces'. Which was hard enough for a layman. I truly enjoyed getting behind some of the reasonings for:
- Vectors
- Symmetri in physical law
- The special theory of relativity
- Relativistic energy and momentum
- Space-Time
- Curved space

The lectures are part of a bigger collection of lectures called: 'The Feynman Lectures'. The Feynman lectures was a freshman and sophomore class for students at CalTech where they would get insight into the marbles of physics.

I enjoyed taking a soft dive into the twelve chapters presented in the 2 short books: 'Six easy pieces' and 'Six not-so-easy pieces'. It gave me some insight and curiosity. But also an understanding of the need to look into and get updated on mathematics before going any deeper. I would think that a great understanding of mathematics would give much more insight than I got. It's been almost 30 years since I had advanced math and psychics in high school.

Great book which I can highly recommend. And I would also use the opportunity to advertise for the 2 great semi biographies of Richard Feynman in form of transcripts of conversations he has had with Ralph Leighton: 'Surely, you're joking Mr. Feynman' and 'What do you care What other people think?'.

Meh. Interestingly, Feynman's introduction itself contains his own criticism of his Lectures in Physics from which this is drawn. The style of presentation must appeal to some large number of people, but I have no real idea what defining features they would have.

This book is an idiosyncratic walk through the most accessible parts of relativity, with some attention paid to the mathematical tools of vectors and symmetry. It's not satisfying for me, but of course I want something oriented toward a physics student rather than a layman.

Pretty aptly titled book. In contrast to "Six Easy Pieces: Essentials of Physics Explained by Its Most Brilliant Teacher", there was a lot more mathematical formalism that was a little tough to follow, but with patience could be understood. The six lectures are put together so you can better understand Einsteins' special and general relativity. The book really made me appreciate the power of mathematics and interpretation to determine the nature of the real world. I actually found out how they determined E=mc^2! The book also had Feynman's characteristic humor and crazy imagination to illustrate really tough physics and mathematics. I really wish Feynman's entire lecture set wasn't so expensive :-(.