We are proposing a new, falsifiable physical model describing the ultra-thin gas. It takes into account the quantum mechanical effect of spreading of the wave function at the level of individual gas particles with realistic nonlocality assumed. The solution of the Schrödinger equation for a free particle is applied to each gas particle independently – during its free time between successive collisions. One of predictions of this model is that such a gas can get almost completely transparent to light and hardly reacts electromagnetically with other physical objects. However, it retains its mass and therefore interacts gravitationally. Such properties make it a candidate to be a component of Dark matter.
An experiment proposed to falsify the theory was conducted. It’s based on the prediction that the measured optical transmittance depends, among others, on the size of the detector used and the duration of the particles mean free time. The classical approach to gas transmittance (the Beer-Lambert law) does not predict the dependence on any of those factors. In the experiment water vapor transmittance was measured simultaneously with two detectors of different size. The experiment was to determine whether the transmittance measured with the smaller detector is greater than the transmittance measured with the larger detector. The objective was achieved with >5σ statistical significance. The fact of observing a non-obvious phenomenon predicted by the theory is a very strong premise for its validity. As far as we know there is no other gas transmittance model predicting such results. Besides, this is an important voice in the discussion on the interpretations of quantum mechanics. In particular it contradicts interpretations postulating localized particles e.g., the pilot wave interpretations.