Is quantum mechanics an effective theory to be replaced?

Determine whether quantum mechanics should be regarded as an effective theory that will ultimately be superseded by a more fundamental physical theory.

Background

The paper references Paul Davies’s formulation of open questions to underscore uncertainty about the foundational status of quantum mechanics. This question directly addresses whether quantum mechanics is merely an effective theory, suggesting the potential for a deeper framework that could resolve current interpretational and integration challenges discussed by the author.

While the paper advances a hypothesis preserving quantum reality and explaining classical perception via decoherence and statistical realizations, it acknowledges the broader frontier where the replacement of quantum mechanics remains an explicitly open consideration.

References

Physicist Paul Davies, in a recent presentation [11], categorizes all concerns of the field under the topic of “open question (minutely rephrased) of quantum mechanics” as follows:

  1. Is quantum mechanics an effective theory to be replaced?
— Quantum Universe and its Elusive Classicality  (2401.17336 - Schad, 2024) in Introduction

In this context, an ambitious question is whether quantum predictions could emerge as an effective description of the world according to some embedded observer. This fits into a broader investigation of how epistemic limitations specified by an operational theory (e.g. quantum theory) jointly constrain the admissible fundamental physical theory (the ontological level), manifest variables, and ready states. This differs from the usual task of constructing a hidden-variable model because the physical constitution of the observer and the informational resources available feature as a part of the explanation. Given a class of physical theories, a failure to recover the operational predictions motivates a revision of deeper assumptions of the model, such as deterministic dynamics or subject--object separability. The present paper does not answer such questions, but it provides a clear example in which some of the relevant concepts can be distinguished.

— The View from Within: What Can Embedded Observers (Not) Learn?  (2608.25800 - Gonda et al., 26 Aug 2026) in Section 'Discussion and Outlook', paragraph 'Beyond nomic toy theory'

Quantum mechanics is the most precisely tested framework in physics, yet the question of whether its probabilistic structure is fundamental or emergent remains open, and a growing experimental program treats it as such: precision bounds on higher-order (Sorkin) interference and on deviations within the landscape of generalized probabilistic theories constrain the very structure of quantum probability, and cloud quantum processors have begun to serve as foundations testbeds .

— Information capacity of quantum statistics: Fock-state tests of a discrete binary-sequence model on cloud photonic quantum processors  (2609.10216 - Wijesundara et al., 9 Sep 2026) in Section 1, Introduction