I've been somewhat interested in differential geometry since my cousin's husband, who did his PhD in astrodynamics, first explained the idea to me several years ago.

This page will start out as notes taken from Functional Differential Geometry, by Sussman and Wisdom. I've loved Abelson and Sussman's Structure and Interpretation of Computer Programs, and I'm hoping to find that the humor and accessibility of that book have carried through into Sussman's other work. Initial indications are positive.

0. Notation

Explained in the prolog is some notation:

1. Introduction

$$ D(\partial_2 L \circ \Gamma[q]) - \partial_1 L \circ \Gamma[q] = 0 $$