From Theories by Lorenz and Mie to Ontological Underdetermination of Theories by Experiments

摘要

In 1908, relying on Maxwell's electromagnetism, Gustav Mie published a theory describing the interaction between an electromagnetic plane wave and a sphere characterised by its diameter and its complex refractive index. A theory treating the same problem has however been published by Lorenz about 20 years before. Furthermore, this theory did not rely on Maxwell's electromagnetism, but did rely on a mechanical theory of ether. Yet, although relying on two deeply different ontologies, both theories generate the same experimental predictions. Experts in epistemology would say that they are empirically equivalent. The existence of conflicting theories being empirically equivalent may be discussed in the framework of a thesis called Quine's thesis of underdetermination of theories by experiments to which this chapter is devoted.