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Feynman's Lecture Notes

Richard Feynman reading notes in Lecture 45, Illustrations of Thermodynamics, May 8, 1962.

About the notes

These are notes Richard Feynman made in 1961-64 to plan and prepare lectures for Caltech's two-year introductory physics course. The originals are preserved by The Caltech Archives in their Feynman Papers collection (Group II, Section 4, folders 39.9, 40.3, 40.4 and 40.5).1 Photos of Feynman giving his undergraduate lectures (such as that above) show he almost always had a few pages of notes to which he referred occassionlly. The pages presented here (at least most) were among the ones he used.2

The 611 pages are presented just as they are currently found in the Caltech Archives3. While it is very clear there is a correspondence between the notes and the lectures in FLP, the notes also contain ideas that Feynman rejected, and other things, such as lesson plans, that are not properly part of the lectures.

Unfortunately, some notes seem to be missing. In particular, there is a dearth of notes on quantum mechanics; these may be hiding in some other part of the Feynman Papers collection. It is hoped that future research will uncover the missing notes so they can be added to this repository.

Viewing the notes

Feynman's notes have been scanned at high resolution, enhanced for readability4, and converted to a deep-zoomable format. They are served by a Cantaloupe IIIF image server, and displayed using OpenSeadragon image viewing software. The notes are presented in an "image viewer" application designed to aid in their organization and study. A description of the image viewer can be found here.

  1. The Caltech Archives maintains a detailed finding aid for The Feynman Papers. (An alternative interface to Caltech's finding aid is hosted by the Online Archive of California.)
  2. Opening the folders initiates transfer of oodles of image data from our server, particularly folder 39.9 because it is so big, so please be patient!
  3. The pages of notes in Feynman’s filing cabinet were likely divided into folders and ordered just as they are presented here, but it's not certain. Caltech Archivist Peter Collopy comments, "Archivists often rearrange in the course of processing a collection. Ideally, we document how we rearrange, but that’s a recent development, so I generally assume that our collections didn’t always have the same arrangement they have now. In this particular case, I doubt anyone understood the notes well enough to rearrange them anyway, so I think we can expect the current arrangement is Feynman’s."
  4. All 611 pages were enhanced for readability by Natallia Piatrenka, who also provided artwork for the notes viewer application.