Entropy is a measure of the disorder or randomness of a system. It is also defined as the amount of energy unavailable to do work. Entropy always increases with time (2nd law of Thermodynamics). One of the many things IT architecture does is to try to reduce disorder or chaos and maximize the amount of energy available for useful work. Perhaps other forms of architecture like that of buildings, machines, animal and plant bodies are also shaped by this endeavour.
In order to reduce chaos, architecture applies patterns, typical ones being cohesion, decoupling and reuse. Entropy in physics has a symbol, S, and a unit of measure, Joules/Kelvin/Kg or Joules/Kelvin/Mol. I wonder if we can define a similar unit of measure for the disorder of an architectural system. Then we would be able to measure the effectiveness of architecture or architectural change, id est how well it reduced wasted energy within the system. It could become an objective measure of the goodness of an architecture, architecture decisions and resultant systems.
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