We approach the physics of minimal coupling in general relativity, demonstrating that in certain circumstances this leads to (apparent) violations of the strong equivalence principle, which states (roughly) that, in general relativity, the dynamical laws of special relativity can be recovered at a point. We then assess the consequences of this result for the dynamical perspective on relativity, finding that potential difficulties presented by such apparent violations of the strong equivalence principle can be overcome. Next, we draw upon our discussion of the dynamical perspective in order to make explicit two 'miracles' in the foundations of relativity theory. We close by arguing that the above results afford us insights into the nature of special relativity, and its relation to general relativity.

I describe how relativistic field theory generalises the paradigm property of material systems, the possession of mass, to the requirement that they have a mass-energy-momentum density tensor T µν associated with them. I argue that T µν does not represent an intrinsic property of matter. For it will become evident that the definition of T µν depends on the metric field g µν in a variety of ways. Accordingly, since g µν represents the geometry of spacetime itself, the properties of mass, stress, energy and momentum should not be seen as intrinsic properties of matter, but as relational properties that material systems have only in virtue of their relation to spacetime structure.

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