Corollary: Continuous-time version

For

the propagator is ${\mathcal{P}}_{e^{-\kappa t}}$. When $\kappa >0$, strict separation survives exactly for

When $\kappa =0$, it survives at every finite delay.

Proof. The identity component is fixed and the traceless component decays as $e^{-\kappa t}$. Apply Theorem thm:retention.