A modelling framework for non-Gaussian transport in complex media

by Dr Vittoria Sposini (DFA UniPD)

Tuesday 14 Jul 2026, 12:00 → 13:00 Europe/Rome

P2A (Dipartimento di Fisica e Astronomia - Edificio Ricci-Curbastro (ex-Paolotti))

The BioSoft@UNIPD seminar series brings together the soft matter and biophysics community of the Department of Physics and Astronomy (DFA) at the University of Padua, focusing on experimental and theoretical advances. Check out the calendar of upcoming seminars here: https://docs.google.com/spreadsheets/d/1Lwer76YmE11IhuvkLbehhgGR4V03mGQwxWAayklhwR0/edit?gid=0#gid=0.  

 

Transport phenomena in soft matter systems play a fundamental role in a wide range of biological and industrial processes. Over the last decades, it has become clear that the motion of diffusive tracers in complex and disordered environments often deviates from classical Gaussian statistics described by standard Brownian motion, instead exhibiting (almost) universally non-Gaussian behaviour. Both analytical and numerical studies have linked non-Gaussian diffusion to sample-to-sample variability and/or spatio-temporal heterogeneity inherent to the system. My talk aims at exploring this phenomenon from two distinct yet complementary perspectives. 

In the first part, I will present a general theoretical framework based on the concept of subordination, which captures the emergence of non-Gaussian diffusion across a broad class of complex systems. I will then focus on a specific case study, investigating how system heterogeneity influences the emergence of non-Gaussian diffusion in the transport of colloidal nanoparticles through a polymeric glassy matrix composed of star polymers. In particular, I will show that the emergence of arrested phase separation in this system interacts with the dynamics of the colloids in a non-trivial manner, leading to complex, multiscale phenomena. Overall, these two perspectives together highlight the importance of system heterogeneity in shaping transport behaviour in complex media.