The philosophical model unpinning a physical model is a “top down” model. The observable spacetime of the physical model emerges from the philosophical reduction of phenomena from a primordial whole.  The philosophical model, in its steps of reduction, includes a crucial step. This is collapse of a quantum mechanical wavefunction.  This collapse is posited to be an act of free will.  As such, it is characterized by indeterminism which cannot be modeled mathematically.  The deterministic physical model follows as that which can be modeled mathematically.  Thus, the model yields a physical model in the traditional sense, but explicitly includes free will that cannot be modeled mathematically.