Flow with spin dissipation. Spin dissipation, , is a relevant parameter that brings the flow out of the conservative plane. Because grows up to infinity with the RG iterations, it is convenient to use the reduced dissipation to represent the flow. If we perturb the active inertial fixed point, z = 1.35, with some dissipation, the RG flow leaves the =0 plane, until it eventually reaches the active overdamped fixed point for =1 (green pyramid), where z = 1.73. When 0 it is better to represent the flow through the reduced inertial coupling, , instead of f, so that in the overdamped limit, =1, we have one less parameter, as the inertial coupling drops out of the calculation. The overdamped fixed point, z = 1.73, is best seen as belonging to the overdamped =1 line, rather than to the conservative but non-inertial line, =0, f = 0. Even though the value of is the same on the two lines, only the first corresponds to the correct overdamped limit. All flow lines are actual numerical solutions of the RG equations.
