The feynman lectures on physics video

Q: Are Feynman Lectures recorded?

These are the tape recordings of Richard Feynmans 1961-64 Caltech Introductory Physics lectures, which form the basis of the book The Feynman Lectures on Physics. The original recordings were made on 1/4 reel-to-reel tapes, now preserved in Caltechs Archive.

Q: Are the Feynman Lectures easy to understand?

Its often said to be too advanced, but its just because its very comprehensive -- NOT difficult -- every part of it is very easy. It builds your physics intuition literally step by step. If you often feel theres a big hole in your understanding after reading some textbooks, it almost never happens here.

Caltech's Division of Physics, Mathematics and Astronomy and The Feynman Lectures Website are pleased to present this online edition of

Table of Contents Show

A Free Education
Lecture 1: The Law of Gravitation
Lecture 2: The Relation of Mathematics to Physics
Lecture 3: The Great Conservation Principles
Lecture 4: Symmetry in Physical Law
Lecture 5: The Distinction of Past and Future
Lecture 6: Probability and Uncertainty — The Quantum Mechanical View of Nature
Lecture 7: Seeking New Laws
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How do I watch Feynman Lectures?
What level is Feynman Lectures on Physics?
Are Feynman Lectures recorded?
Are the Feynman Lectures easy to understand?

Feynman • Leighton • Sands

Now, anyone with internet access and a web browser can enjoy reading2 a high quality up-to-date copy of Feynman's legendary lectures.

This edition has been designed for ease of reading on devices of any size or shape; text, figures and equations can all be zoomed without degradation.3

For comments or questions about this edition please contact Michael Gottlieb.

Richard Feynman talking with a teaching assistant after the lecture on The Dependence of Amplitudes on Time, Robert Leighton (left) and Matthew Sands (right) in background, April 29, 1963.

Contributions from many parties have enabled and benefitted the creation of the HTML edition of The Feynman Lectures on Physics. We wish to thank

Carver Mead, for his warm encouragement and generous financial support, without which this edition would have been impossible,
Thomas Kelleher and Basic Books, for their open-mindedness in allowing this edition to be published free of charge,
Adam Cochran, for tying up the many slippery loose ends that needed to come together in order for this edition to be realized,
Alan Rice for his steadfast enthusiasm for this project, and for rallying the support of Caltech's Division of Physics, Mathematics and Astronomy.

Clicking the "Restore my view" link will take you back to where you last left off reading, or you can restore your view directly by loading a special URL, feynmanlectures.caltech.edu#restore - bookmark it for convenience. The "Restore my view" link and URL will become active only after you've closed one of the chapters of this edition. For view restoration to work properly you may need to clear your browser cache of our pages. ↩
However, we want to be clear that this edition is only free to read, look at and listen to online, and this posting does not transfer any right to download all or any portion of the book The Feynman Lectures on Physics, its photos or tape recordings, for any purpose. ↩
This HTML5-based edition features LaTeX equations rendered by MathJax JavaScript, and scalable vector graphic (SVG) figures. Your browser must support javascript and permit scripts from mathjax.org. LocalStorage must be enabled. We recommend using a modern browser; some older browsers may not display this edition correctly. PNG figures (that degrade when scaled) may be served to browsers that do not support SVG. We do not support versions of Internet Explorer older than 9.0. For information about MathJax features and accessibility options, right-click on any display equation. ↩
The lecture recordings can also be played in their respective FLP chapters. ↩
Links to the photos also appear near the title of each FLP chapter. ↩
Updated in March 2022 with a new presentation featuring deep-zoomable images. ↩

A Free Education

The Feynman Lectures is one of the most popular lecture series in physics. It's a great resource for science enthusiasts, students, teachers — basically everyone. Now, Caltech and The Feynman Lectures website have collaborated to put these lectures online. And they are completely free.

The lectures themselves were first presented at Caltech in the 1960s by the legendary physicist Richard Feynman. The lectures have since been combined into a three-volume book. To date, about 1.5 million English copies have been sold, but now that it's free, that number will probably stagnate.

You can start with Volume 1, Volume 2, or Volume 3 of the book via the lecture series' website or simply watch the lectures below. They contain the same information as the books, so you can actually feel like you were sitting in Feynman's class when he gave his lectures 50 years ago.

Lecture 1: The Law of Gravitation

Lecture 2: The Relation of Mathematics to Physics

Lecture 3: The Great Conservation Principles

Lecture 4: Symmetry in Physical Law

Lecture 5: The Distinction of Past and Future

Lecture 6: Probability and Uncertainty — The Quantum Mechanical View of Nature

Lecture 7: Seeking New Laws

How do I watch Feynman Lectures?

What level is Feynman Lectures on Physics?

The Feynman Lectures are considered to be one of the most sophisticated and comprehensive college-level introductions to physics.

Are Feynman Lectures recorded?

These are the tape recordings of Richard Feynman's 1961-64 Caltech Introductory Physics lectures, which form the basis of the book The Feynman Lectures on Physics. The original recordings were made on 1/4" reel-to-reel tapes, now preserved in Caltech's Archive.

Are the Feynman Lectures easy to understand?

It's often said to be too advanced, but it's just because it's very comprehensive -- NOT difficult -- every part of it is very easy. It builds your physics intuition literally step by step. If you often feel there's a big hole in your understanding after reading some textbooks, it almost never happens here.