Idealization and Idealized Models in Thermostatistical Physics

University Of Florida, Gainesville FL

Investigators

Abstract

SES 99-10889 - Chuang Liu (University of Florida) "Idealization and Idealized Models in Thermostatistical Physics" The goal of this project is develop of a philosophical theory of idealization in light of a study of the intricate practice of model-building in thermostatistical physics. The structure of the overall argument goes as follows. The existing theory of idealization and its relation to approximation is found to be inadequate. The problem is then shown to be caused by a misunderstanding of the purpose (and therefore the measure) of idealization. It is therefore argued that idealization is not necessarily to postulate conditions which are themselves approximate or whose gradual removal guarantees approximate laws and/or models, but to carve nature at its joints -- obtaining theoretical models as a result -- so that genuine laws of nature can be either applied (if they are already known) or discovered (if they are not yet known). While such an intuitive notion of idealization gives the right, albeit inarticulate, characterization of the widespread practice of model-building in science, it defies an exact and universal formulation. To understand the rich content of this notion, one must conduct detailed analysis of its different guises in different fields of science. Thermostatistical physics is chosen for this project because it is the best understood branch of science which cuts across the microscopic and the macroscopic divide. The project provides a detailed study of various models in the explanation of phase transitions and critical phenomena. By examining the kind of ideal conditions going into the making of what the PI calls the approximate and the exact models, he shall develop a glimpse of how the notion of carving nature at its joints is put to work. The PI hopes that this project will motivate himself and others to study the practice of idealization- and model-making (since they always go hand--in-hand) in other areas of physics (or science).