Asymptotics of the Wigner 9j-symbol

作者:Haggard Hal M*; Littlejohn Robert G
来源:Classical and Quantum Gravity, 2010, 27(13): 135010.
DOI:10.1088/0264-9381/27/13/135010

摘要

We present the asymptotic formula for the Wigner 9j-symbol, valid when all quantum numbers are large, in the classically allowed region. As in the Ponzano-Regge formula for the 6j-symbol, the action is expressed in terms of lengths of edges and dihedral angles of a geometrical figure, but the angles require care in definition. Rules are presented for converting spin networks into the associated geometrical figures. The amplitude is expressed as the determinant of a 2 x 2 matrix of Poisson brackets. The 9j-symbol possesses caustics associated with the fold and elliptic and hyperbolic umbilic catastrophes. The asymptotic formula obeys the exact symmetries of the 9j-symbol.

  • 出版日期2010-7-7