Quantum ontology and intuitions

Décio Krause

Paull Nunez

Ontological questions, concerning the nature of reality, continue to be argued in both the scientific and general literature, and new experiments may be proposed to move ontological questions into the instrumental category for resolution. This chapter contends that all interpretations of quantum mechanics are weird when considered from classical, everyday viewpoints. Readers holding classical world views should not expect to find intuitively-pleasing explanations of quantum mechanics; scientists much smarter than us have failed in this quest over the past century.

Anubhav Chaturvedi, Debashis Saha

Based on an intuitive generalization of the Leibniz principle of `the identity of indiscernibles', we introduce a novel ontological notion of classicality, called bounded ontological distinctness. Formulated as a principle, bounded ontological distinctness equates the distinguishability of a set of operational physical entities to the distinctness of their ontological counterparts. Employing three instances of two-dimensional quantum preparations, we demonstrate the violation of bounded ontological distinctness or excess ontological distinctness of quantum preparations, without invoking any additional assumptions. Moreover, our methodology enables the inference of tight lower bounds on the extent of excess ontological distinctness of quantum preparations. Similarly, we demonstrate excess ontological distinctness of quantum transformations, using three two-dimensional unitary transformations. However, to demonstrate excess ontological distinctness of quantum measurements, an additional assumption such as outcome determinism or bounded ontological distinctness of preparations is required. Moreover, we show that quantum violations of other well-known ontological principles implicate quantum excess ontological distinctness. Finally, to showcase the operational vitality of excess ontological distinctness, we introduce two distinct classes of communication tasks powered by excess ontological distinctness.

Hilary Putnam

Sisir Roy

Nadji Belkheiri

Scientific textbook diagrams traditionally present electrons as planetary bodies traversing determinate orbits. While quantum mechanics has long superseded this classical framework, the visual grammar of the planetary atom remains deeply ingrained in pedagogy and scientific communication. This paper argues that the philosophical significance of this persistence extends beyond the simple observation that diagrams can be misleading. To explain this phenomenon, I introduce the concept of representational inertia: the survival of an inherited visual or representational structure after the theoretical commitments that originally licensed it have been rendered obsolete, alongside the continued recruitment of the ontological intuitions encoded within that structure. Tracing the transformation from classical orbit to quantum-mechanical orbital, this essay examines how replacement visual constructs such as the probability "cloud" can themselves invite reification and import classical spatial intuitions. The paper clarifies the interpretation-dependence of quantum ontology, distinguishes representation from visualization, addresses the role of decoherence in the measurement problem, and contrasts representational inertia with related notions such as reification, theory-ladenness, and Bachelardian epistemological obstacles. Finally, actionable guidelines are proposed for scientific visualization and pedagogy to mitigate the unintended projection of classical ontology in quantum contexts and beyond.