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An efficient algorithm for the Riemannian 10j symbols

J. Daniel Christensen·Greg Egan
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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.

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J. Daniel Christensen, Greg Egan. 2002-01-24. An efficient algorithm for the Riemannian 10j symbols. https://doi.org/10.1088/0264-9381%2F19%2F6%2F310

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