Neil Dewar (Munich): “On Absolute Units”

What is the best way to characterise the intrinsic structure of physical quantities? Field’s program shows one approach (that also delivers a nominalist treatment of such quantities); in this talk, I outline how group-theoretic methods can deliver a somewhat simpler, although non-nominalist, way of doing this for scalar and vector quantities. I go on to develop a theory on how such quantities can be algebraically combined, and use this to develop a simple intrinsic treatment of Newtonian gravitation. Finally, I argue that this treatment illuminates a “third way” in the debate over absolutism and comparativism about quantities: namely, a form of anti-quidditist absolutism.