The Dual-Slit Experiment Myth


The results of this classic experiment were garbled long ago. The misinformation has prompted a spurious metaphysical explanation, where mundane physics suffices:-


There are two classic dual-slit experiments. In the first, both slits are illuminated. The second holds that light is made to pass through only one.  The accepted error is that there is no difference between the two respective interference patterns. As will be explained, this is not so.

In the latter, light “quanta” passing through one slit are, perforce, represented as knowing of the presence of the second. Worse, it has become accepted that a “quantum” of light can be in two places at once!

This legacy has engendered much of the illogicality in QM and the “dual nature” of light has acquired near-total credence. Indeed it has become a matter of perverse pride that QM is not logical. A best-selling author wrote:

“Quantum entities not only seem  to be able to pass through both holes at once, but to have an awareness of past and future, so that each can choose to make its own contribution to the interference pattern in just the right place to build the pattern up without destroying it”.


“The quantum entities seem to know when you are watching them and adjust their behaviour accordingly. Each single quantum entity seems to know about the whole experimental set-up, including when and where the observer is choosing to monitor it, and about the past and future of the experiment”.

But the two interference patterns are very different, as made plain by Max Born. In 1935, in his book “Atomic Physics” Blackie and Son, he contrasted the two patterns: the first, with all the maxima “equally bright”, the other, where “their intensity falls off from the middle outwards”.

This mimics pairs of radio antennae. Not surprising. Since both radio and light waves are electromagnetic, both engender interference when two or more sources interact. Radiation diagrams  below show the contrasts at both radio and light frequencies.

Radio and optical interference compared

Radio and optical interference compared

Hence :

1. A wave-front can, at once, impinge on both adjacent slits.
2. Light behaves much like radio waves.
3. Slits and antennae are both resonant elements.
4. Both can absorb and re-radiate incident electromagnetic energy.
5. A slit can behave like a driven antenna element.
6. A slit can also behave like an undriven (parasitic) antenna element.
7. Two adjacent illuminated slits correspond to the two driven antennae of a standard radio interferometer.
8.  Electrons and light “quanta are members of a self-similar fractal hierarchy.


From the radio antenna paradigm:-

Telecomm. technology provides a better explanation of the dual-slit experiment than does the quasi-scientific version.

Slits behave like tuned (resonant) antenna elements.

No evidence is apparent here of particles/photons or of wave/ particle duality. Light is apparent only after the incidence of electromagnetic waves on macro surfaces (groups of atoms).

The purported “awareness” and “consciousness” are neither manifest nor pertinent. Similarly the concept of “Existence through Observation”.

The radio equivalent of an un-illuminated slit is the un-driven, or parasitic, element of the standard Yagi (TV) antenna. As in fig 2b above

The inference is that De Broglie’s quantum frequency changes are more likely than positional jumps,  which also fits in with the idea that the universe is fractally organised.