On the Semantics of Entropy Measures of Emergent Phenomena

This paper is an attempt to perform some semantic analysis of the concept of "entropy" as it is used in both thermodynamic and non-thermodynamic contexts. We will first consider the relation between thermodynamic entropy as a semantic concept, a measured quantity of real systems; and statistical entropy as a syntactic concept, a calculated quantity in formal systems. We will then consider the use of entropy as a measure of different types of systems, the origin and identification of emergent levels in physical systems, and the ontological status of non-thermodynamic entropies. 1 Syntactic vs. Semantic Definitions of Entropy The literature on the relation between thermodynamics and information theory is vast [8, 10, 23, 26, 51, 61, etc.]. While this debate is not the central concern of this paper, in any discussion of entropy it is wise to clearly express how it will be understood. We do so on the basis of the relation and difference between, on the one hand, quantities which result fr..