The Wave-Particle Duality—Does the Concept of Particle Make Sense in Quantum Mechanics? Should We Ask the Second Quantization?

Abstract

The quantum object is in general considered as displaying both wave and particle nature. By particle is understood an item localized in a very small volume of the space, and which cannot be simultaneously in two disjoint regions of the space. By wave, to the contrary, is understood a distributed item, occupying in some cases two or more disjoint regions of the space. The quantum formalism did not explain until today the so-called "collapse" of the wave-function, i.e. the shrinking of the wavefunction to one small region of the space, when a macroscopic object is encountered. This seems to happen in "which-way" experiments. A very appealing explanation for this behavior is the idea of a particle, localized in some limited part of the wavefunction. The present article challenges the concept of particle. It proves in base of a variant of the Tan, Walls and Collett experiment, that this concept leads to a situation in which the particle has to be simultaneously in two places distant from one anothersituation that contradicts the very definition of a particle. Another argument is based on a modified version of the Afshar experiment, showing that the concept of particle is problematic. The concept of particle makes additional difficulties when the wave-function passes through fields. An unexpected possibility to solve these difficulties seems to arise from the cavity quantum electrodynamics studies done recently by S. Savasta and his collaborators. It involves virtual particles. One of these studies is briefly described here. Though, experimental results are expected, so that it is too soon to draw conclusions whether it speaks in favor, or against the concept of particle. KeywordsQuantum mechanics, wave-particle duality, empty waves, first quantization, second quantization.Abbreviations 1PWF = single-particle wave-function dBBI = de Broglie-Bohm interpretation EBS = end-beam-splitter GRW = Ghirardi, Rimini, Weber QM = quantum mechanics U.V. = ultra violet

The Quantum Mechanics <i>Needs</i> the Principle of Wave-Function Collapse—But This Principle Shouldn’t Be <i>Misunderstood</i>

“…Vis-à-vis this claim, Section 3 of [35] presents a contradiction between the dBB mechanics and QM, reasoning within one single frame of coordinates. Its main line is described below.…”

“…The relevant trials of the experiment are those in which all the three detectors D 1 , D 2 , and D 3 , click. The calculi in [35] showed that for the phase-shifts 1) The w-p a triggers the detector D 1 , and the detectors D 2 and D 3 are triggered by the oscillators; Figure 2. An arrangement for simultaneous detections of one particle in different places.…”

In Praise and in Criticism of the Model of Continuous Spontaneous Localization of the Wave-Function

“…The de Broglie-Bohm interpretation of QM is based on the assumption of particles floating inside the wave-function and following continuous trajectories. The existence of such continuous trajectories was disproved in [5] Section 3.…”

What Was in the Apparatus before the Click of the Detector?

“…If the w-f consists of several w-ps, the particle travels with one of them, and the rest of the w-ps are considered some sort of really existing waves, though to which the detectors are insensitive. However, a strong argument was brought against the dBB mechanics in [18]. 2 What was challenged in [18] wasn't the existence of a particle as a substructure of the QM formalism.…”

“…However, a strong argument was brought against the dBB mechanics in [18]. 2 What was challenged in [18] wasn't the existence of a particle as a substructure of the QM formalism. The possibility of a continuous trajectory for the alleged particle was proved incompatible with the QM predictions.…”