Posted in Code, Math, Physics, Projects

Lie Group Computations With Python

lie is a python module for computations with Lie groups, Lie algebras, representations, root systems, and more.

I based it on the computer algebra package LiE, written by M. A. A. van Leeuwen, A. M. Cohen and B. Lisser in the early 90’s. They chose to implement a proprietary scripting language as a wrapper for all the fancy mathematical algorithms. While this language is useful for interactive computations and short scripts, python is more expressive and powerful — definitely what you want when exploring your favorite exceptional group.

A Fun Example

Here’s an example of using lie to do a calculation that’s near and dear to every high energy theorist’s heart. We’ll show how the 10 + 5bar + 1 representation of SU(5) contains a single standard model generation. First we’ll fire up python and import the lie module. Continue reading…

Posted in Code, Humor, Physics, Projects

The snarXiv

The snarXiv is a random high-energy theory paper generator incorporating all the latest trends, entropic reasoning, and exciting moduli spaces. The arXiv is similar, but occasionally less random.

Actually, the snarXiv only generates tantalizing titles and abstracts at the moment, while the arXiv delivers matching papers as well. Details of the implementation are below. I’m the author, and I don’t remember exactly why I decided to do this. I did already have the framework lying around from a previous project, and I swear I spent more time doing research last weekend than implementing snarXiv.org.

Suggested Uses for the snarXiv

Posted in Code, Projects

The Real Theorem Generator: a Context Free Grammar

I should probably document the real origin of the Theorem of the Day and Philosophy of the Day. Coffee and Henry David Thoreau are perhaps less involved than originally indicated.

nothoreauThe theorem generator was written by a good friend of mine, Matt Gline, as a project for CS51: Abstraction and Design in Computer Programming, which we took together as freshmen.

The assignment was to use LISP to implement a context free grammar — basically a set of rules for computer-generated mad libs. The subject was whatever we wanted. Good ones from past years include computer-generated mystery novellas, course-guide reports, and performance art directions. Every year there’s a contest, and Matt’s theorem generator was hysterical enough to win him lunch at the faculty club. Continue reading…