The two laws of engines in general, information and the meaning of entropy

Abstract

The association of information with entropy has been argued on plausibility arguments involving the operation of imaginary engines and beings, and it is not a universal theorem. In this paper, a theorem by Charles Bennett on reversible computation is recognized as the much needed theorem. It is proposed a real, non thermal engine, operated by humans. Its operation has stages analogous to the stages in Bennett's reversible three-tape computer. The engine makes possible to prove two results: (1) the engine operates on two laws, similar to the laws of thermodynamics, which are conditions on the possibility of resetting the engine; (2) entropy is the measure of erased information, and is measured in physical units, which complies with Landauer's principle. A prototype at work is shown in video.