Einstein's Relativity - Chapter 4 (Annotated‪)‬

Einstein's Relativity - The Best Introduction to the Theory of Relativity! - Chapter 4: The Inertial Frame of Reference
- Written by Einstein himself for the popular audience!
- A Completely New and Modern Translation, 2024-2026!
- Fully annotated

Note: This focused booklet contains Chapter 4 in its entirety, providing a digestible entry point into Einstein's masterwork.


This book was originally written in German, by Einstein, in 1916, and it was first published in 1917 in Germany. After WWI, thanks to the growing recognition of the work of Einstein, and of Einstein himself, it was finally translated into English in 1920. It became an instant bestseller in multiple languages. After over 100 years, for anyone who wants to learn relativity, at a conceptual level, this book still remains the best introduction to the theory of relativity.

Unfortunately, for the English-speaking readers, the original translation was somewhat archaic, and it made Einstein's original intent unnecessarily difficult to understand. If you ever tried to read this book, and you were disappointed due to the opaque language, then this new edition is for you. If you ever wanted to learn relativity as a non-physicist, and couldn't find a good introductory book, then this book is for you. You will learn relativity in a completely new way, as if Einstein himself were speaking directly to you.

It is still not an easy book to read. Relativity is not an easy subject. Unlike many popular science books that avoid math entirely, Einstein includes essential equations, presenting them with unmatched clarity. To make his revolutionary insights more accessible, we are publishing this series of single-chapter booklets featuring a fresh, modern translation (2026). We hope that some readers will find these short novella-style booklets easier to digest than more traditional single book formats.

You will also realize that a good translation makes a huge difference. Compare this new translation with the public-domain books of the original English translation, which is now over 100 years old.