A proposal for the experimental detection of CSL induced random walk

TL;DR

This paper explores experimental methods to detect CSL-induced random walk by analyzing particle diffusion effects, proposing that such effects can be observed at higher pressures than previously thought, using current technology.

Contribution

It revisits prior CSL diffusion analysis, demonstrating that detectable effects occur at higher pressures, and proposes feasible experimental setups for detection.

Findings

CSL diffusion can be observed at pressures around a pico-Torr.

CSL effects dominate environmental noise at low temperatures and pressures.

Proposed experimental setups are feasible with current technology.

Abstract

Continuous Spontaneous Localization (CSL) is one possible explanation for dynamically induced collapse of the wave-function during a quantum measurement. The collapse is mediated by a stochastic non-linear modification of the Schrodinger equation. A consequence of the CSL mechanism is an extremely tiny violation of energy-momentum conservation, which can, in principle, be detected in the laboratory via the random diffusion of a particle induced by the stochastic collapse mechanism. In a paper in 2003, Collett and Pearle investigated the translational CSL diffusion of a sphere, and the rotational CSL diffusion of a disc, and showed that this effect dominates over the ambient environmental noise at low temperatures and extremely low pressures (about ten-thousandth of a pico-Torr). In the present paper, we revisit their analysis and argue that this stringent condition on pressure can be relaxed, and that the CSL effect can be seen at the pressure of about a pico-Torr. A similar analysis is provided for diffusion produced by gravity-induced decoherence, where the effect is typically much weaker than CSL. We also discuss the CSL induced random displacement of a quantum oscillator. Lastly, we propose possible experimental set-ups justifying that CSL diffusion is indeed measurable with the current technology.