4. Out of Equilibrium Systems
This term deals with physics systems that are not in thermodynamic equilibrium and can represent the extrapolation of different variables. This concerns the transport process and the rates of chemical reactions.
Almost all systems that are found in nature and our everyday lives are not in thermodynamic equilibrium because they are always changing and can be triggered over time. They are always subject to the changes in matter and energy that come from other systems and reactions.