|  Clebsch-Gordan Theory / Coefficients | 
In General
  > s.a. angular momentum; group representations;
  SU(2) [6j, 10j symbols].
  * Idea: Mathematical
    symbols used to integrate products of spherical harmonics, or add
    angular momenta in quantum mechanics.
  $ Def: The coefficients
    C jm1,
    m2
    = \(\langle\) j1
    j2
    m1
    m2
    | j1
    j2,
    j m\(\rangle\), with
|j, m\(\rangle\) = ∑m1+m2=m \(\langle\) j1 j2 m1 m2 | j1 j2, j m\(\rangle\) |m1 m2\(\rangle\) , j1 + j2 = j.
* Properties:
\(\langle\) j1 m1, j2 m2 | j m\(\rangle\) = (−1) j1+j2−j \(\langle\) j2 m2, j1 m1 | j m \(\rangle\) .
* Relationships: In terms of 6j-symbols,
    \[ \langle\, j_{_1}\,j_{_2}m_{_1}m_{_2}\vert\, j_{_1}j_{_2},j\,m\, \rangle
    = (-1)^{-j_1+j_2-m}\,\sqrt{\vphantom{\sqrt1}2j+1}
    \left(\matrix{j_{_1} & j_{_2} & j \cr m_{_1} & m_{_2} & -m}\right) .\]
* Theorem: πj ⊗ πj' = πj+j' ⊕ πj+j'−1 ⊕ ··· ⊕ π| j−j' |.
References
  @ Calculation:
    Klink & Wickramasekara EJP(10) [simple method];
    Horst & Reuter CPC(11)-a1011 [CleGo computer package];
    Ibort et al a1610 [numerical algorithm].
  @ Asymptotics: de Guise & Rowe JMP(98),
    Reinsch & Morehead JMP(99).
  @ For SU(3): Coleman JMP(64);
    Grigorescu SCF(84)mp/00;
    Prakash & Sharatchandra JMP(96),
    Rowe & Repka JMP(97) [and SU(2)];
    Rowe & Bahri JMP(00).
  @ Other groups: Asherova et al PAN(01)m.QA [Uq(su(3))];
    Wu mp/06 [permutation group].
  > Online resources:
    see MathWorld page;
    Wikipedia page
    and table.
 main page
  – abbreviations
  – journals – comments
  – other sites – acknowledgements
  send feedback and suggestions to bombelli at olemiss.edu – modified 4 oct 2016