SU(2) Special Unitary 2x2 : Unitary with det=1
( α − β ¯ β α ¯ ) {\displaystyle {\begin{pmatrix}\alpha &-{\bar {\beta }}\\\beta &{\bar {\alpha }}\end{pmatrix}}}
행렬식이 1이므로 | α | 2 + | β | 2 = 1 {\displaystyle |\alpha |^{2}+|\beta |^{2}=1}
이고, α = α 0 + i α 1 {\displaystyle \alpha =\alpha _{0}+i\alpha _{1}} , β = β 0 + i β 1 {\displaystyle \beta =\beta _{0}+i\beta _{1}} 라고 하면
