The Steady State: A Question of Balance

Abstract

There is no perfect steady state, or condition of complete equilibrium. But just as the invention of the number, zero, was necessary and profound, the condition of the steady state is crucial to modeling. The steady state is considered to be a condition in which the total amount of material entering a system exactly equals the amount leaving the system; moreover, the amount of material entering each defined kinetic compartment must exactly equal the amount leaving that compartment. It is a condition of balance in which there is no net change in mass over time.

If I ask you whether your brain is an equilibrium system, all I have to do is ask you not to think about elephants for a few minutes, and you know it isn’t an equilibrium system.