The Necessary Structure of the All-pervading Aether: Discrete or Continuous? Simple or Symmetric?

Abstract

This book is an investigation into the necessary structure of the aether - the stuff that fills the whole universe. (I assure readers that it is not the sort of aether that could have a current in it - the aether wind that Michelson and Morley famously failed to detect.) Assuming what I call the aether exists, we lack knowledge of its structure. In fact one of my aims is to exhibit the immense variety of structures that, for all we know, it could have. Here I use the words 'know' and 'knowledge' with neither litotes nor hyperbole - we lack knowledge because the available arguments do not establish their conclusions 'beyond all reasonable doubt'. Nonetheless, we can form reasonable beliefs about its structure. I shall argue that it has no point parts: either the aether is composed of granules that are extended atoms; or it is point-free (gunky) in that every part is the sum of parts of less extension (diameter). In particular, the aether does not have the structure of orthodox Space-time. To say it had that orthodox structure would be to say that the aether was the mereological sum of uncountably many points, and that every non-empty set of points had a mereological sum. The granules or gunk disjunction is more specific than the grit (i.e. discrete) or gunk thesis I have previously defended (2004). For I am able to argue against the thesis of Point Discretion, namely that every part of the aether of finite diameter has finitely many point parts.