CSL reduction rate for rigid bodies

TL;DR

This paper analyzes the CSL collapse rate for rigid bodies, demonstrating that continuous mass distribution approximations are accurate and revealing a novel mass difference effect influencing the reduction rate.

Contribution

It provides a detailed comparison of exact and approximate CSL collapse rates, introducing the concept of a mass difference effect and its relation to the layering effect.

Findings

Continuous mass distribution accurately reproduces the exact collapse rate.

Identification of a mass difference effect influencing the reduction rate.

Link between the layering effect and the mass difference effect.

Abstract

In the context of spontaneous wave function collapse models, we investigate the properties of the Continuous Spontaneous Localization (CSL) collapse rate for rigid bodies. By exploiting the Euler-Maclaurin formula, we show that for standard matter the rate for a continuous mass distribution accurately reproduces the exact rate (i.e. the one for a point-like distribution). We compare the exact rate with previous estimates in the literature and we asses their validity. We find that the reduction rate displays a peculiar mass difference effect, which we investigate and describe in detail. We show that the recently proposed layering effect is a consequence of the mass difference effect.