On the fundamentally probabilistic nature of the knowledge of a microsystem in the framework of the Elementary Process Theory

TL;DR

This paper demonstrates that even with a deterministic model of elementary processes, our knowledge of a neutron's position remains fundamentally probabilistic, highlighting a key interpretational issue in quantum mechanics.

Contribution

It shows that the Elementary Process Theory, despite being deterministic, cannot fully account for the probabilistic nature of quantum measurement outcomes.

Findings

Deterministic models do not eliminate fundamental quantum probabilities.

EPT is incompatible with orthodox quantum mechanics.

EPT aligns with $pistemic$ interpretations of QM.

Abstract

A fundamental question in the debate about the interpretations of quantum mechanics (QM) is whether the universe is fundamentally deterministic or fundamentally probabilistic. This self-contained paper shows for a microsystem made up of a single neutron that is initially at rest in a stationary force-free environment, that even if the individual processes by which the microsystem evolves are fundamentally deterministic as described by a strictly deterministic model of the Elementary Process Theory (EPT), then still our most precise knowledge of the outcome of a position measurement on the microsystem is fundamentally probabilistic. Generalizing, the conclusion is that the EPT is inconsistent with orthodox QM, but consistent with $\psi$-epistemic QM.