xPert: Computer algebra for metric perturbation theory
General Relativity and Quantum Cosmology
2009-09-28 v1
Abstract
We present the tensor computer algebra package xPert for fast construction and manipulation of the equations of metric perturbation theory, around arbitrary backgrounds. It is based on the combination of explicit combinatorial formulas for the n-th order perturbation of curvature tensors and their gauge changes, and the use of highly efficient techniques of index canonicalization, provided by the underlying tensor system xAct, for Mathematica. We give examples of use and show the efficiency of the system with timings plots: it is possible to handle orders n=4 or n=5 within seconds, or reach n=10 with timings below 1 hour.
Keywords
Cite
@article{arxiv.0807.0824,
title = {xPert: Computer algebra for metric perturbation theory},
author = {David Brizuela and Jose M. Martin-Garcia and Guillermo A. Mena Marugan},
journal= {arXiv preprint arXiv:0807.0824},
year = {2009}
}
Comments
11 pages, 4 figures. Package can be downloaded from http://metric.iem.csic.es/Martin-Garcia/xAct/xPert/