Nico Stollenwerk (Basque Center for Applied Mathematics, BCAM)
Biography
Nico Stollenwerk is a biomathematician specializing in population biology and complex systems. With extensive experience in European projects on influenza and dengue fever, he is currently a Senior Researcher at the Basque Center for Applied Mathematics (BCAM) in Bilbao. He is also an active member of the Basque Modeling Task Force (BMTF), contributing to COVID-19 research and modeling efforts.
"Import driven large fluctuations in critical and subcritical percolation, state of the art and future perspectives"
After introducing the notions of directed percolation (with a prime example in epidemiology being the SIS spatially extended stochastic system at and around the epidemiological threshold) and dynamical isotropic percolation (with the prime example being the SIR system), we show a simple renormalization scheme in the time domain to describe self-similarity at criticality and scaling near criticality. The we will charactrize the large fluctuations in subcritical epidemiological systems, which are driven by small import (in the limit of import vanishing), which is important in practical applications like invasion scenarios of vector-borne diseases [1], as well as prviosuly investigated during the COVID-19 pandemic after lockdown lifiting, avoiding supercitical explosion of infected but approaching the epidemiological threshold [2]. Technical aspects have been tackled since some time [3] (like Fock space representation of stochastic processes and path integrals), but now adjusted to the present scientific questions, relevant for the practical applications and data analysis.
References
[1] Stollenwerk, N., Mateus, L., Steindorf, V., et al. (2024). Evaluating the risk of mosquito-borne diseases in non-endemic regions: A dynamic modeling approach (under review).
[2] Aguiar, M., Bidaurrazaga Van-Dierdonck, J., Mar, J., et al. (2021). Critical fluctuations in epidemic models explain COVID-19 post-lockdown dynamics. Scientific Reports, 11: 13839.
[3] Stollenwerk, N., Jansen, V. (2011). Population Biology and Criticality: From critical birth–death processes to self-organized criticality in mutation pathogen systems. Imperial College Press, World Scientific, London.
