Examples of entropy: from physics to nature

Abstract This paper aims to give a short history of how the concept of entropy has been developed and how it is used today in diverse scientific disciplines in our quest for understanding ourselves and our environment. The first part of the paper gives a historical perspective, which starts with the invention of the first heat engines, continues with the verbal formulation of the laws of thermodynamics and ends with the formulation of the mathematical equations that tell the complete story of thermodynamics by describing the transport of mass, momentum, energy and entropy. The second part of the paper focusses on the use of entropy beyond heat engines and shows how entropy has influenced the thinking in scientific disciplines such as chemistry, biology, ecology, communication, economy and sociology. Both a historical summary and the examples presented in this paper are limited to within the domain of classical mechanics. Although entropy has ignited powerful ideas and has many uses in both relativistic and quantum mechanics, these are not within the scope of this paper.