Robert A. McNees

Most people who come here are looking for my online notes on Conventions, Definitions, Identities, and Formulas for folks working in GR, string theory, and related fields.


Occasionally I write out some of my notes and stick them here for easy access. They probably are not useful to anyone else, but if you do find them useful please let me know. Be careful: anything that you find here is probably full of typos!


Conventions, Definitions, Identities,
and Other Useful Formulae
An older, pdf version of these notes. Thanks to Juan Jottar for catching a typo in a previous version.

The ADM Decomposition
A quick and dirty review of the geometry underlying Arnowitt, Deser, and Misner's Hamiltonian approach to General Relativity.

Particle Physics Formula Sheet
Reference sheet for an undergraduate Particle Physics course. Unfortunately, the (+,-,-,-) signature is used throughout.

The Eightfold Way
A visual reference for Murray Gell-Mann's Eightfold Way. From the same course as the particle physics formula sheet.



I use LaTeX for everything from letters to presentations. Here are some useful templates and examples that I've put together. Feel free to use and modify any of them. Let me know if you make anything interesting!


Spacetime Diagrams for Uniformly Accelerated Observers
Programmatically draw the spacetime diagram for a uniformly accelerated observer using the TikZ/PGF package for LaTeX. Related code for drawing an accelerating rocket with constant proper length can be found here.

A Simple Letter Template for LaTeX
A LaTeX template for letters with a simple letterhead that includes your school's logo. Replace the file signature.pdf to add your scanned signature to the closing.

Graph Paper with LaTeX
Update: Leo Stein and I turned this into a LaTeX package. It is now available through CTAN. If you have a modern TeX installation, you probably have this package already!

I use a lot of graph paper. Like, a lot of graph paper. So when my stockpile of Tops quadrille pads is running low I use LaTeX to make my own. This simple tex file produces quadrille paper with 8 or 10 squares per inch, gridded paper like an engineering pad, hex grids, or even square grids with light cones for drawing causal diagrams! All in whatever color you like. There is now a github repo for this code. The most recent version of this code can always be found there.