hep-lat/0205013. Generalized Lattice Gauge Theory, Spin Foams and State Sum Invariants, Robert Oeckl, hep-th/0110259. Spin Networks in Gauge Theory, John C. Baez
,則得到同一維數的Pin群的複表示,稱為旋量表示(英语:spinrepresentation)。若再限制到旋量群 S p i n p , q ( R ) {\displaystyle \mathrm {Spin} _{p,q}(\mathbb {R} )} 上,則該表示分解成兩個半旋量表示(half spin representations,又稱外爾表示,Weyl