I am interested in philosophy of physics, philosophy of science, and philosophy of mathematics, particularly in relation to foundational questions in quantum theory, relativity, and cosmology.
My current research is on the identification of objects, relative to a physical theory, by the definition of predicates in terms of values of quantities invariant under the symmetries of that theory. The ontology — the set of objects arrived at in this way, as given by the domain of quantification — is required to satisfy a principle of identity of indiscernibles, where identity is defined by exhaustion of predicates. I am interested in the adequacy of ontology in this sense to explanation and inter-theory relations in the physical sciences. In the background are more general questions, of the continuity of ontology through theory change, and of the role of mathematical structure, over and above ontology, in physical theories.