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arXiv · 1104.5315

Asymptotic Analysis of the Wigner $3j$-Symbol in the Bargmann Representation

Liang Yu
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Abstract

We derive the leading asymptotic limit of the Wigner $3j$-symbol from a stationary phase approximation of a twelve dimensional integral, obtained from an inner product between two exact Bargmann wavefunctions. We show that, by the construction of the Bargmann inner product, the stationary phase conditions have a geometric description in terms of the Hopf fibration of ${\mathbb C}^6$ into ${\mathbb R}^3 \times {\mathbb R}^3 \times {\mathbb R}^3$. In addition, we find that, except for the usual modification of the quantum numbers by 1/2, the imaginary part of the logarithm of a Bargmann wavefunction, evaluated at the stationary points, is equal to the asymptotic phase of the $3j$-symbol.

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Liang Yu. 2011-04-28. Asymptotic Analysis of the Wigner $3j$-Symbol in the Bargmann Representation. https://arxiv.org/abs/1104.5315

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