The burden of Fundamentality: Metaphysical ambiguities and the issue of Superdeterminism

TL;DR

The paper scrutinizes superdeterminism as a scientific program by distinguishing naïve (NSD) and metaphysical (MSD) variants and examining their epistemic and metaphysical commitments. It argues that NSD relies on illegitimate fundamentality claims, treating fundamentality as a precondition rather than a conclusion, which shifts the view from science to metaphysics. The most developed MSD example, Invariant Set Theory (IST), is shown to entangle physics with a problematic, non-spatiotemporal holistic metaphysics and a contentious mereology of parts and wholes. The authors conclude that fundamentality should be demonstrated rather than assumed, and that current SD proposals face deep methodological and metaphysical challenges, with implications for the philosophy of physics and quantum foundations.

Abstract

In this paper we approach the problem of superdeterminism from a novel point of view, highlighting its character as a more metaphysical than scientific proposition. First, we introduce a distinction between two types of superdeterministic theories, naïve (NSD) and metaphysical (MSD), and argue how NSD presents significant epistemic flaws. We show how NSD justifies itself through claims to fundamentality, thus connoting itself as a metaphysical theory rather than a scientific one. We finally illustrate that the most developed MSD model so far, Invariant Set Theory, implicitly proposes a confused form of priority monism. Our paper thus reinforces the thesis that theories should demonstrate rather than assume fundamentality and that it is methodologically flawed for a theory to assume its own fundamentality for the sole purpose of defending against criticisms.

Figures (2)

• Figure 1: Two different SI-violating models, for a bipartite scenario where the two parts are spacelike separated (e.g., the CHSH scenario ClauserShimonyHolt1969). Arrows in black indicate causal dependencies common between the model and a Statistical Independence-preserving Local Hidden Variable Model; red arrows indicate the causal dependencies by which the model violates Statistical Independence. a. Superdeterministic models: the hidden variables ($\lambda$ determines the measurement settings (a and b). b. Future Input-Dependent models: the measurement settings $a$ and $b$ retrocausally determine the hidden variables ($\lambda$). This means that mathematically $\lambda$ is correlated with $a$ and $b$, while physically it means that in some sense---which differs depending on the model---the settings $a$ and $b$ cause $\lambda$. In every model, however, retrocausal signalling is typically not allowed, i.e., no information can travel backward in time.
• Figure 2: Simplified diagram of the CHSH experiment ClauserShimonyHolt1969. A source emits pairs of spin-entangled particles in opposite directions. The left-hand particle (A) is subjected to either test $a_0$ or $a_1$, while the right-hand particle (B), is subjected to either test $b_0$ or $b_1$, with each test having $+1/-1$ as possible results.

Theorems & Definitions (16)

• Definition 2.1
• Definition 2.2
• Definition 4.1
• Definition 4.2
• Proposition 1
• Definition 6.1: Priority Monism
• Definition 6.2: Priority Monism (cosmic)
• Definition 6.3: Priority Pluralism
• Definition 6.4: Priority Pluralism (partial)
• Proposition 2