Full Idea
Thomson famously objects that the doctrine of temporal parts is 'a crazy metaphysic - obviously false', since it entails that material objects are constantly being generated ex nihilo (or, at least, the stuff of which they are composed is).
Gist of Idea
Temporal parts is a crazy doctrine, because it entails constantly creating stuff ex nihilo
Source
report of Judith (Jarvis) Thomson (Parthood and Identity across Time [1983], p.210) by Kathrin Koslicki - The Structure of Objects 2.2
Book Reference
Koslicki,Kathrin: 'The Structure of Objects' [OUP 2008], p.25
A Reaction
The related objections are to ask what the temporal 'width' of a part is, and whether the joins are visible.