The question of how a cell controls its size is an one, which despite decades of research is still timely because the old experiments have been unable to measure the heterogeneity of cell populations which can be measured today in new generations of experiments based on the observation and manipulation of single cells.

We are developing a theoretical framework based on analogies between population genetics and Stochastic Thermodynamics to relate fluctuations at the single cell level to  qprobabilistic behaviour at the level of the population [1]. We use this theory to characterize a statistical bias present in the two levels of description, and some of its consequences in terms of mean division times. From the study of stochastic models, in which cells divide at a rate which may depend on their age or size, we hope to gain some understanding on which factors are relevant in the modelling of cell populations and how to these factors affect the population growth rate.

 [1] Linking lineage and population observables in biological branching processes, R. Garcia-Garcia, A. Genthon and D. Lacoste, Phys. Rev. E, 042413 (2019).