SU(2) Adjoint Orbit
su(2) generators:
Jₓ,Jᵧ,J_z basis
[Jₓ,Jᵧ] = iJ_z
Adj orbit of p ∈ su(2):
sphere S² of fixed |p|
State on Bloch sphere:
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SU(2) adjoint action: Ad_g(X) = gXg⁻¹. Orbits in su(2) ≅ ℝ³ are 2-spheres of fixed radius. Commutator flow [H,X] = adₕ(X) generates rotations on Bloch sphere. Spin-1/2 dynamics.