  We demonstrate an unexpected connection between isotropic turbulence and
wall-bounded shear flows. We perform direct numerical simulations of isotropic
turbulence forced at large scales at moderate Reynolds numbers and observe
sudden transitions from a chaotic dynamics to a spatially simple flow,
analogous to the laminar state in wall bounded shear flows. We find that the
survival probabilities of turbulence are exponential and the typical lifetimes
increase superexponentially with the Reynolds number. Our results suggest that
both isotropic turbulence and wall-bounded shear flows qualitatively share the
same phase-space dynamics.
