Quantum discreteness is an illusion

TL;DR

The paper argues that quantum particle concepts are illusions arising from decoherence, and that wave-particle duality is obsolete, emphasizing a smooth, non-degenerate interpretation of quantum states.

Contribution

It presents a novel interpretation of quantum phenomena, showing how particle notions emerge from decoherence without requiring actual particles or wave-particle duality.

Findings

Quantum numbers can be interpreted as occupation numbers of field modes.

Decoherence explains apparent particle positions and events without actual particles.

Wave function probabilities do not correspond to local elements of reality.

Abstract

I review arguments demonstrating how the concept of "particle" numbers arises in the form of equidistant energy eigenvalues of coupled harmonic oscillators representing free fields. Their quantum numbers (numbers of nodes of the wave functions) can be interpreted as occupation numbers for objects with a formal mass (defined by the field equation) and spatial wave number ("momentum") characterizing classical field modes. A superposition of different oscillator eigenstates, all consisting of n modes having one node, while all others have none, defines a nondegenerate "n-particle wave function". Other discrete properties and phenomena (such as particle positions and "events") can be understood by means of the fast but smooth process of decoherence: the irreversible dislocalization of superpositions. Any wave-particle dualism thus becomes obsolete. The observation of individual outcomes of this decoherence process in measurements requires either a subsequent collapse of the wave function or a "branching observer" in accordance with the Schr\"odinger equation - both possibilities applying clearly after the decoherence process. Any probability interpretation of the wave function in terms of local elements of reality, such as particles or other classical concepts, would open a Pandora's box of paradoxes, as is illustrated by various misnomers that have become popular in quantum theory.