The Minimally Physically Derivable Theories (MPDT) metatheory establishes four independently motivated conditions that any fundamental physical theory must satisfy: computationally representable space, a single fundamental indivisible constituent of matter, momentum as a primitive conserved property, and exactly two opposing forces. These conditions follow from methodological requirements on what any predictive physical theory must do, not from any specific physical ontology. This paper applies the MPDT metatheory systematically to the six major current programs in fundamental physics: the Standard Model, quantum field theory as a framework, canonical loop quantum gravity, covariant loop quantum gravity, string theory, causal set theory, and asymptotic safety. For each program, the paper identifies which conditions it fails and why, which ad hoc assumptions the failure generates, whether those assumptions correspond to the program's recognised failure modes, and whether the failure is contingent or structural. Every program fails at least one condition structurally — as a necessary consequence of its foundational commitments rather than a remediable technical deficiency. The failures cluster around two root causes: the import of the mathematical continuum and the import of physical time. Version 3 extends the string theory evaluation with two additions. First, a dedicated section establishes that the string theory failure is not only that the string lacks indivisibility, but that a one-dimensional object cannot physically exist in discrete volumetric preonic space at any scale: the preon (−) is the fundamental unit of volume, so one-dimensional and two-dimensional objects have zero volume and no physical realisation. This dimensionality failure is prior to and independent of the indivisibility failure. Second, a section addresses the Cheung–Remmen–Sciotti–Tarquini (2026) amplitude bootstrap result — which derives the Veneziano amplitude uniquely from ultrasoft Regge behaviour and residue minimality — and gives the correct QGD reading: the Veneziano amplitude is the finite prescription (in the sense of P36) for preonic scattering in the continuum limit, not evidence for one-dimensional strings as fundamental constituents. The QGD section is also updated to include the native Word block equations for G⁺ (a;b), G⁻ (a;b), G (a;b), the threshold condition k = (d²_Λ + d_Λ) /2, and E (p⁺) = P (p⁺) = c̃. References are updated to include P36 (Continuous Mathematics as Finite Prescriptions) and P37 (Extended Falsifiability of QGD). Keywords: MPDT, metatheory, fundamental physics, Standard Model, loop quantum gravity, string theory, causal set theory, asymptotic safety, conditions for fundamentality, ad hoc assumptions, continuum import, physical time, three-dimensional volume primitive, Axiomatic Imperative, QGD, finite prescriptions
Daniel Burnstein (Wed,) studied this question.