Eq. (21) indicates that the rate of change of potential can reduce the overall rate of entropy production. The rate of change
of potential energy takes the system to a new equilibrium and even if there is constant heat input to the system such that it
results in a corresponding change in potential energy, the system can remain in equilibrium. In the absence of any potential
energy changes, the entropy production is only determined by the change in energy of the system.
We can rewrite Eq. (21) in terms of the Lagrangian of the system,