Entropy
lastmod 2018-08-17created 2015-02-043 edits
Entropy is a state function used to describe the flow of energy in a thermodynamic system that is not useful (cannot be converted into work).
In statistical mechanics, it can be thought of as the logarithm of the number of microstates corresponding to a given macrostate.
Entropy is generally not conserved and increases over time according to the second law of thermodynamics. It was introduced by the German physicist Rudolf Clausius in the early 1850s. The Latin capital letter S is usually used as its symbol.