English

An efficient algorithm for the Riemannian 10j symbols

General Relativity and Quantum Cosmology 2009-11-07 v3

Abstract

The 10j symbol is a spin network that appears in the partition function for the Barrett-Crane model of Riemannian quantum gravity. Elementary methods of calculating the 10j symbol require order(j^9) or more operations and order(j^2) or more space, where j is the average spin. We present an algorithm that computes the 10j symbol using order(j^5) operations and order(j^2) space, and a variant that uses order(j^6) operations and a constant amount of space. An implementation has been made available on the web.

Cite

@article{arxiv.gr-qc/0110045,
  title  = {An efficient algorithm for the Riemannian 10j symbols},
  author = {J. Daniel Christensen and Greg Egan},
  journal= {arXiv preprint arXiv:gr-qc/0110045},
  year   = {2009}
}

Comments

9 pages, 5 postscript figures. This is the version that is to appear in Classical and Quantum Gravity. See also http://jdc.math.uwo.ca/spin-foams