Suppose g = a semi-simple Lie algebra over C G = the corresponding adjoint group B = a Borel subgroup of G T = a Cartan subgroup of B b, t = corresponding Lie algebras Σ = roots corresponding to the choice of t ∆ = simple roots corresponding to the choice of b W = the Weyl groupNG(T )/T . For each α in ∆, let eα 6= 0 be an element of the root space gα. The triple (b, t, {eα}) is called a frame ...