Gribbin (1990: 172-3):

In the simplest experiment with two holes, the interference of probabilities can be interpreted as if the electron that leaves the gun vanishes once it is out of sight, and is replaced by an array of ghost electrons that each follows a different path to the detector screen. The ghosts interfere with one another, and when we look at the way the electrons are detected by the screen we then find the traces of this interference, even if we deal only with one "real" electron at a time. However, this array of ghost electrons only describes what happens when we are not looking; when we look, all of the ghosts except one vanish, and one of the ghosts solidifies as a real electron. In terms of Schrödinger's wave equation, each of the "ghosts" corresponds to a wave, or rather a packet of waves, the waves that Born interpreted as a measure of probability.

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*(Note that here the author, like many physicists, in saying what happens when we are not looking, unwittingly violates the Copenhagen Interpretation of Quantum Physics. As Feynman cautioned, this is to produce an error.)*

From the perspective of Systemic Functional Linguistic theory, the interference of probabilities construes the **potential** of the system, as instantiated by the statistical distribution of particles.

When the electron is out of sight, it does not "vanish"; the electron, as an instance of meaning, is simply no longer being construed. Nor is the electron replaced by an array of ghost electrons taking different paths to the detector; the notion of an 'array of ghost electrons' misconstrues the **potential** of the probabilistic system (wave) as statistical instances (particles). Nor, therefore, do 'the ghosts interfere with one another', and 'the traces of interference' construes the statistical distribution of particles that instantiates the probabilities of the system as potential.

When we look, therefore, there is no vanishing of ghosts, and no solidifying of one ghost as a real electron. In looking, experience is being construed as meaning: as one instance (particle) of the system as potential (wave of probability).