Test of a theory of the Mott quantum-measurement problem

TL;DR

This paper investigates whether a quantum-mechanical mechanism can explain the formation of non-spherical tracks from spherically symmetric nuclear decays, testing a theoretical 1/R^2 law against cloud chamber data.

Contribution

It proposes and tests a quantum-mechanical explanation for the Mott problem, connecting theory with experimental cloud chamber observations.

Findings

The 1/R^2 probability law is supported by data within a factor of 2.

The estimated proportionality constant aligns with theoretical predictions.

The approach links quantum scattering theory with observable track patterns.

Abstract

The Mott problem asks: Is there a microphysical mechanism - based only on Schroedinger's equation - that explains why an alpha particle emitted in a spherically symmetric nuclear decay produces a non-spherically-symmetric single track in a cloud chamber? This is a variant of the more general quantum measurement problem. Earlier, I proposed such a mechanism, drawing on quantum-mechanical Coulomb scattering and the thermal behavior of supersaturated vapors. I found that the probability that a track originates at distance R from the decay source is proportional to 1/R^2, with a proportionality constant that I expressed in terms of more fundamental parameters but was unable to estimate at the time. I tested the 1/R^2 law opportunistically using cloud chamber video from the Internet. Here, I draw on chemical physics to independently estimate the proportionality constant. The estimate is within a factor 1-2 of a value extracted directly from the data.