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arXiv · 1105.4220

Uniform Approximation from Symbol Calculus on a Spherical Phase Space

Liang Yu
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Abstract

We use symbol correspondence and quantum normal form theory to develop a more general method for finding uniform asymptotic approximations. We then apply this method to derive a result we announced in an earlier paper, namely, the uniform approximation of the $6j$-symbol in terms of the rotation matrices. The derivation is based on the Stratonovich-Weyl symbol correspondence between matrix operators and functions on a spherical phase space. The resulting approximation depends on a canonical, or area preserving, map between two pairs of intersecting level sets on the spherical phase space.

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Liang Yu. 2011-05-21. Uniform Approximation from Symbol Calculus on a Spherical Phase Space. https://doi.org/10.1088/1751-8113/44/50/505202

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