Mean field mutation dynamics and the continuous Luria-Delbr\"uck distribution

The Luria-Delbr"uck mutation model has a long history and has been mathematically formulated in several different ways. Here we tackle the problem in the case of a continuous distribution using some mathematical tools from nonlinear statistical physics. Starting from the classical formulations we derive the corresponding differential models and show that under a suitable mean field scaling they correspond to generalized Fokker-Planck equations for the mutants distribution whose solutions are given by the corresponding Luria-Delbr"uck distribution. Numerical results confirming the theoretical analysis are also presented.