The Free Physics Textbook

How do objects and images, empty space and people move? What is motion?

How do colours appear? What do love, fireworks and butterflies have in common? How do muscles work? Is levitation possible? What does ‘quantum’ mean? Is time travel possible? What is the maximum force found in nature? Is the universe a set? Which problems in physics are still open?

Exploring these questions with this text will provide as much pleasure as whatever you enjoy most – whether it is watching a sunset, listening to music, painting, making love, or anything else.

Download edition 23.5 (of October 2009) here.

This free textbook presents the science of motion: physics. The book is written for curious men, women, boys and girls: it is entertaining, surprising and challenging on every page. With little mathematics, starting from observations of everyday life, the text presents the most fascinating aspects of things that move. It explores mechanics, thermodynamics, special and general relativity, electrodynamics, quantum theory and modern attempts at unification. The essence of these fields is summarized in the most simple terms possible. For example, the text presents modern physics as consequence of the notions of minimum entropy, maximum speed, maximum force, minimum change of charge, and minimum action.

For each field of physics, the text presents the best stories, the latest research results, the best animations, the best images, the most interesting physical puzzles and the most telling physical curiosities. It includes more than 700 animations, films and illustrations, 120 tables, 1900 challenges and puzzles, and 1100 internet links.

The five volumes on modern physics are meant for students, teachers, and for anybody who is curious about the precise description of nature. To satisfy even the most extreme curiosity, the text adds a sixth volume that explores the limits of time and space, and the wonders that can be discovered there. There are over 2000 pages written in English. The first 700 pages are available in the French language, 100 pages are available in the Italian language, 80 pages are available in the Spanish language, and 100 pages are available in the German language.

Motion Mountain is downloaded over 30 000 times a year, since many years. It aims to be among the best introductory physics texts available. If you have an idea for improving it, add it to the suggestion wiki: I will try to implement it. For a valuable suggestion, I will add you to the acknowledgment list, to the sponsor list, or send you a reward.