Light
| Scientific Theory | |
|---|---|
| Name | Light |
| Type | Physical phenomenon and its disputed nature |
| Author(s) | Nature disputed — see the researchers listed below |
| Keywords | light, photon, wave–particle duality, luminic motion, aether, speed of light, Particle Model |
Light is the most contested phenomenon in physics. Everyone agrees on what light does — it propagates, refracts, diffracts, interferes, carries energy in discrete amounts, and travels at a definite speed. What no one has satisfactorily explained is what light is.
Orthodox physics answers with wave–particle duality: light behaves as a wave in some experiments and as a particle in others, and this is declared a fundamental feature of nature rather than a defect in the account. The critical tradition documented on this wiki treats that answer as an evasion. A duality is not an explanation but a contradiction given a name — and the persistence of the contradiction for over a century is read here as evidence that the underlying model is wrong, not that nature is inscrutable.
Accordingly this wiki catalogues a substantial literature offering physically intelligible models of light: accounts in which light is something definite, made of something, moving in a describable way.
The orthodox account
In the standard treatment light is an electromagnetic wave in Maxwell's theory, and simultaneously a stream of quanta — photons — carrying energy E = hν. Quantum electrodynamics computes the outcomes of experiments to extraordinary precision. But QED is explicitly a calculational formalism, not a picture: it declines to say what a photon is between emission and detection, and treats the question as improper. Critics observe that a theory which forbids the question has not answered it.
The particle solutions
Robert de Hilster: luminic motion
In 2015, while trying to describe light waves in terms of particles, the engineer Robert de Hilster proposed a direct resolution of the duality. Light, on his account, is made of waves of particles — successive groups of real particles travelling together at the speed of light, "like successive waves of bombers."
The proposal is attractive because of what it explains without extra assumptions:
- Frequency is the rate at which the groups arrive — a genuine periodicity, requiring no oscillating medium and no field.
- Intensity is the number of particles in each group. This is the point conventional wave models handle awkwardly and pure photon-counting models handle only statistically; here both properties fall out of one picture, because a group of particles has both a spacing and a population.
There is thus no duality to reconcile: light is particles, and the wave is the pattern in which the particles travel. De Hilster named this luminic motion, and it became one of the four universal motions he and his son David de Hilster set out in Principia Mathematica 2 and The Four Universal Motions in Physics. It forms part of the wider Particle Model developed by the two, in which light, gravity and matter are all built from real sub-atomic particles. See also his Light, Gravity, and Mass: A Particle Theory (2015).
David de Hilster: the electromagnetic wave is a graph, not an object
Where Robert de Hilster supplies a positive model, David de Hilster supplies the corresponding critique: that the familiar textbook picture of light — two perpendicular sine waves, electric and magnetic, advancing through space — is a graph of a mathematical relationship dressed up as a physical object. It is a plot of field magnitudes, and a plot is not a thing.
He presses three questions the diagram cannot answer:
- What is each field made of? The picture shows something oscillating "up" and something oscillating "sideways," but never says what is being displaced. A wave is a disturbance of something; the diagram names no medium and no substance.
- What links the two fields? The electric and magnetic components are held to be inseparable and exactly synchronized — but that connection is asserted by the geometry of the drawing, not produced by any stated mechanism.
- Why is there no interference? Countless rays cross the same region of space at every moment without disturbing one another. If light were literally a planar field filling that space, they should interact; the model offers no account of why they do not.
He locates the origin of the problem in Maxwell. Maxwell's equations yielded a propagation speed numerically equal to the measured speed of light, and from that numerical coincidence the conclusion was drawn that light is an electromagnetic oscillation. On this reading Maxwell succeeded in describing relationships between forces — which his equations do superbly — while never establishing what the things themselves are. The description was then mistaken for the object.
The alternative follows the same discipline as the rest of the Particle Model: light is particles in motion rather than a wave in an unnamed medium; magnetism arises from particles spiralling around a conductor; and a "field" is a description of where particles are and how they move, not an invisible entity in its own right. On this account the three questions above do not arise, because nothing is being asked to oscillate except real objects with real trajectories.
See "Electromagnetic Waves" at fourmotions.org.
Other corpuscular accounts
- Robert A Kerr — Light Is Transmitted By Photons, arguing for transmission by real particles rather than field oscillation.
- Zifeng Li — Particle nature of light and the speed of light, connecting a particle account of light to the question of its measured speed.
- Neil E Munch — Possible Nature of Light and other Emissions and The Possible Nature of Light Emissions.
Photon structure models
A second family of work accepts the photon but insists it must have structure — that a particle carrying frequency, polarization and angular momentum cannot be a dimensionless point:
- Chandrasekhar Roychoudhuri — a leading figure in this literature, author of The Nature of Light: What is a Photon? and, with Al F Kracklauer, The Nature of Light.
- Philipp M Kanarev — Photon Model, proposing a definite geometric structure.
- Further proposals catalogued here include A Model of the Photon, Electromechanical Physical Model of the Photon, A Proposal for an Alternative Model of the Photon and A Model for a Classical Photon.
Neither wave nor particle
Some researchers reject both horns of the dilemma. Bill Gaede argues in Light: Neither Particle nor Transverse Wave that light is neither a discrete corpuscle nor a transverse oscillation, and that the standard alternatives are both artefacts of an inadequate mechanical vocabulary.
Others seek a genuine synthesis rather than a choice: Robert E French presents one in Wave Particle Unity and a Physically Realist Interpretation of Light, and Rati Ram Sharma in A New Light on the Nature of Light. Wave and Particle Theory of Light applied to the Photoelectric Effect tests such a unified reading against the experiment usually held to settle the matter in favour of particles.
Propagation and the speed of light
If light is a real thing moving through a real medium, its speed should behave like the speed of anything else — and much work here disputes the claim that it is invariant for all observers:
- Stephan J G Gift — Light Speed Invariance is a Remarkable Illusion.
- Ruyong Wang — proposed crucial experiments to test light-speed constancy directly, including First-Order Fiber-Interferometric Experiments for Crucial Test of Light-Speed Constancy.
- Joseph A Rybczyk — The True Nature of Light Propagation.
- Related papers include Light projection velocity and not light velocity that is measured as constant, Is the Velocity of Light Constant in Time? and The Constancy of the Speed of Light.
This work connects directly to the wider critique of special relativity, whose second postulate is precisely the constancy of c, and to the aether tradition, in which light propagates through a medium that supplies a preferred frame. See also Sagnac Effect and GPS, where the one-way behaviour of light signals is measured directly.
The common thread
The models above disagree sharply with one another — particles, structured photons, neither, both. What unites them is the conviction that "it is both and you may not ask further" is not an answer, and that a phenomenon as ordinary as light ought to admit of a picture a person can hold in mind. That demand for intelligibility, rather than any single model, is what this body of work has in common.
Further material is indexed under Category:Light and Category:Aether.