Statistical Mechanics

Alexander Franklin (King's College London)
The universality of critical phenomena may be explained by appeal to the Renormalisation Group (RG). Batterman and Morrison, among others, have argued that this explanation is irreducible. In this paper I offer a reduction of the RG account by demonstrating that the key assumption on which it relies - the scale invariance of systems at the critical point - can be explained in lower-level terms. This does not mean that we should replace the RG explanation with a bottom-up account, rather we should acknowledge that the explanation appeals to dependencies which may be traced down to lower levels.

Casey McCoy (University of Edinburgh)
Demarest asserts that we have good evidence for the existence and nature of an initial chance event for the universe. I claim that we have no such evidence and no knowledge of its supposed nature. Against relevant comparison classes her initial chance account is no better, and in some ways worse, than its alternatives.

Joshua Luczak (Leibniz Universität Hannover)
Much of the literature on modelling in science is concerned with representational models. Despite their importance, distinct nature, and presence, toy models, on the other hand, which are a kind of nonrepresentational model, are rarely discussed. This paper hopes to remedy this situation. It aims to elevate the status of toy models: by making clear and elaborating on the distinction between toy models and representational models, by highlighting and elaborating on a way in which the Ehrenfests' urn model, a simple statistical mechanical model, has been used as a toy model, and by explaining why it can be successfully used in this way without performing a representational function.