Noether's theorem derivation of the conservation of the LRL vector A is elegant, but has one drawback: the coordinate variation δx i involves not only the position r, but also the momentum p or, equivalently, the velocity v. This drawback may be eliminated by instead deriving the conservation of A using an approach pioneered by Sophus Lie. Specifically, one may define a Lie transformation in which the coordinates r and the time t are scaled by different powers of a parameter λ (Figure 9), t → → λ λ 3 t , r → → λ λ 2 r , p → → 1 λ λ p .