The non-Gaussian tops and tails of diffusing boomerangs

Koens, Lyndon; Lisicki, Maciej; Lauga, Eric

Abstract

Experiments involving the two-dimensional passive diffusion of colloidal boomerangs tracked off their centre of mobility have shown striking non-Gaussian tails in their probability distribution function [Chakrabarty et al., Soft Matter, 2016, 12, 4318]. This in turn can lead to anomalous diffusion characteristics, including mean drift. In this paper, we develop a general theoretical explanation for these measurements. The idea relies on calculating the two-dimensional probability densities at the centre of mobility of the particle, where all distributions are Gaussian, and then transforming them to a different reference point. Our model clearly captures the experimental results, without any fitting parameters, and demonstrates that the one-dimensional probability distributions may also exhibit strongly non-Gaussian tops. These results indicate that the choice of tracking point can cause a considerable departure from Gaussian statistics, potentially causing some common modelling techniques to fail.

Citation

Koens, L., Lisicki, M., & Lauga, E. (2017). The non-Gaussian tops and tails of diffusing boomerangs. Soft matter, 13(16), 2977-2982. https://doi.org/10.1039/c6sm02649d

• Journal Article Type: Article
• Acceptance Date: Mar 24, 2017
• Online Publication Date: Mar 24, 2017
• Publication Date: 2017
• Deposit Date: Jan 25, 2022
• Journal: Soft matter
• Print ISSN: 1744-683X
• Electronic ISSN: 1744-6848
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 13
• Issue: 16
• Pages: 2977-2982
• DOI: https://doi.org/10.1039/c6sm02649d
• Public URL: https://hull-repository.worktribe.com/output/3916592