The Ontological Status of Information in Physics

Abstract

While the inclusion of information theoretical concepts into (quantum) physics has shown enormous success in recent years, the ontology of information remains puzzling. Therefore, this thesis aims to contribute to the debate about the ontological status of information in physics. Most of the recent debates have focused on syntactic information measures and especially Shannon Information, a concept originally stemming from Communication Theory. This thesis incorporates another syntactic information measure, the so far largely underrepresented notion of Algorithmic Information or Kolmogorov Complexity, a concept often applied in Computer Science. Shannon Information and Kolmogorov Complexity are linked through Coding Theory and have similar characteristics. Through the comparison of Shannon Information and Kolmogorov Complexity a framework is developed which analyses the respective information measures in relation to uncertainty and semantic information. In addition, this framework investigates whether information can be regarded a material entity and examines to what extent information is conventional. It turns out that in the classical case Shannon Information and Kolmogorov Complexity are both abstract and highly conventional entities, which must not be confused with uncertainty and do not bear any relations with semantic information. Virtually the same results are obtained in the quantum case, save for the high degree of conventionality; it is argued that Quantum Theory constrains the conventional choices of those who wish to use either theory.