The dual wave-particle nature of quantum objects is a notoriously unintuitive feature of quantum theories. However, it is often deemed essential, due to quantum objects exhibiting diffraction and interference. We extend the work of Landé and Lévy-Leblond to demonstrate that de Broglie wavelengths are not relativistically covariant as simultaneous spatial structures, making wave properties an unviable explanation of apparent interference. We then explore whether modern experiments vindicate an alternative view: that apparent waviness in diffraction and interference scenarios emerges as a consequence of quantised interactions between particles. Such a view has historically received very little attention, despite being the exact modern explanation of both the Kapitza-Dirac effect and ultrafast electron diffraction. We then study a photon orbital angular momentum realisation of the double slit to show that quantised exchanges can mimic interference. Finally, we demonstrate that the quantum formalism demands that particle momentum is determined at the point of scattering, contravening wave-based explanations of quantum interference.
The dual wave-particle nature of quantum objects is a notoriously unintuitive feature of quantum theories. However, it is often deemed essential, due to quantum objects exhibiting diffraction and interference. We extend the work of Landé and Lévy-Leblond to demonstrate that de Broglie wavelengths are not relativistically covariant as simultaneous spatial structures, making wave properties an unviable explanation of apparent interference. We then explore whether modern experiments vindicate an alternative view: that apparent waviness in diffraction and interference scenarios emerges as a consequence of quantised interactions between particles. Such a view has historically received very little attention, despite being the exact modern explanation of both the Kapitza-Dirac effect and ultrafast electron diffraction. We then study a photon orbital angular momentum realisation of the double slit to show that quantised exchanges can mimic interference. Finally, we demonstrate that the quantum formalism demands that particle momentum is determined at the point of scattering, contravening wave-based explanations of quantum interference.
Abstract Chapter 11 introduces the essential mystery of quantum mechanics, shows how it is resolved, and then goes on to examine related phenomena. The mystery is how individual photons, not electromagnetic waves, can give rise to the interference pattern seen in the two-slit experiment. They are shown to do so because the relevant quantum amplitude is a linear combination of two terms, leading to the pattern when neither slit is identified as the one the photon went through, but collapsing to one term and no pattern if the slit is identified. Similar results are shown to occur when individual electrons are incident on the two slits, and when large molecules, which have de Broglie wavelengths, are scattered by diffraction gratings. Many other interference experiments are described, including those where a photon was shown to be in two places simultaneously and one where a photon displayed both wave and particle features.
Quantum mechanics is characterized by several distinctive features: (1) wave–particle duality, (2) the uncertainty principle, (3) superposition of states, (4) wave function collapse, (5) the tunneling effect, (6) quantum entanglement, and (7) the dominance of probability. Proposed interpretations include the Copenhagen interpretation, the de Broglie–Bohm pilot-wave theory, and the many-worlds interpretation. Despite sustained debate, no unified consensus has emerged. A central obstacle may lie in the unresolved ambiguity over whether a quantum entity is fundamentally a wave or a particle. Although photons and electrons exhibit wave-like and particle-like properties, the concepts of “wave” and “particle” are inherently mutually exclusive. This paper proposes that the true nature of a quantum is a quantized wave interacting at a single spatial point. Based on this premise, the study investigates the vacuum structure and interactions, together with the relationship between wave function collapse and the conservation of physical quantities. The mechanisms underlying the photoelectric effect and quantum tunneling are reexamined, along with the double-slit and delayed-choice quantum eraser experiments. By treating photons and electrons as quantized waves confined to point interactions, this work demonstrates that puzzling quantum behaviors, long considered obstacles to a coherent understanding of quantum mechanics, admit straightforward explanations.
Abstract Quantum interference is often seen as a manifestation of intrinsic wave–particle duality, invoking self-interference and wavefunction superposition. We propose an alternative causal framework where interference arises from interactions between a classical electron and a quantized electromagnetic field. Electrons follow definite, localized trajectories and yield discrete detection events. The wave-like interference pattern emerges statistically from stochastic, nonlocal momentum transfers mediated by quantized field modes. Simulations of double-slit experiments show that dot-like fringes arise without wavefunction collapse or intrinsic wave behavior. Doubling the electron mass narrows fringe spacing in line with de Broglie scaling, suggesting the effective wavelength results dynamically from field coupling, not as an inherent particle trait. This interpretation preserves classical realism while reproducing quantum interference as an emergent, ensemble-level phenomenon. It provides a deterministic account grounded in structured field interactions. In this view, wave–particle duality of electrons reflects the wave nature of photons—the massless U(1) gauge bosons mediating the field—rather than being a fundamental property of matter.
Any discussion of the nature of light must include a reminder that whenever we make the observation of light (photons), we only observe particle-like properties. This paper provides a reiteration that we don't need wave-like properties to scattered photons to describe phenomena such as diffraction or refraction of light. This paper updates the original ideas of Duane, later revived by Lande, which provided a description of light diffraction without making reference to a wave nature. These are updated using terminology more common to quantum electrodynamics which describes the interaction of particles in terms of the exchange of virtual photons. Diffraction is described in terms of an ensemble of distinct, probability weighted paths for the scattered photons. The scattering associated with each path results from the quantized momentum exchange with the scattering lattice attributed to the exchange or reflection of virtual photons. The probability for virtual particle exchange/reflection is dependent upon the allowed momentum states of the lattice determined by a Fourier analysis of the lattice geometry. Any scattered photon will exhibit an apparent wavelength inversely proportional to its momentum. Simplified, particle-like descriptions are developed for Young's double slit diffraction, Fraunhofer diffraction and Fresnel diffraction. This description directly accounts for the quantization of momentum transferred to the scattering lattice and the specific eigenvalues of the lattice based upon the constraints to virtual photon exchange set by the Uncertainty Principle, Δπi = h/ζi.
Arguments about particles or waves gave way to a recognized need for both particles and waves in the description of radiation. The confusion over particle versus wave properties was resolved by Louis de Broglie. He postulated that since light has a dual wave–particle nature, matter also has this nature. The idea was to perform a diffraction experiment with electrons. An interference pattern was demonstrated not only with electrons, but also with many kinds of material particles like protons and neutrons. However, any attempt to observe an interference pattern with neutral atoms was found difficult by the fact that atoms carried no charge as electrons do and could not penetrate through condensate matter like neutrons. The de Broglie wavelength of an electron in the smallest orbit turns out to be exactly equal to the circumference of the orbit predicted by Bohr. The interpretation of the interference phenomenon becomes more subtle when the light beams are replaced by individual photons or particles.
Here, the concept of a wave-particle duality is questioned. First, the experimental proofs existing, respectively, for particles and waves are examined. In the case of particles, no experimental evidence can be found which establishes them; it seems that particles have always been taken for granted. In the case of waves, considerable evidence has accumulated with results on diffraction, interference, and self-interference of larger and larger objects. Then an important remark is made concerning the fact that unlike particles, waves are not observation-dependent: waves existed before observation otherwise the patterns of diffraction or interference would not have been appearing; the wave nature does not depend on the making of a measurement, there is no measurement problem for waves. Consequently, since waves are not observation-dependent, if the objects are demonstrated to be waves, they are only waves. This fact, along with some other evidence, disagrees with the current interpretation of the Wheeler-type delayed-choice experiments, where the absence of interference is interpreted as a particle behavior. Finally, recent works regarding the de Broglie‐Bohm theory are presented, which lead to suggest a new wave-only version of this theory. It is concluded that a wave-only view might be worth considering instead of the wave-particle duality view which has prevailed so far.