A discussion on some simple epidemiological models

The present text discusses some basic considerations on the dynamics of the coronavirus pandemic, in particular in France. The goal is not to make accurate predictions, which is probably impossible, but to illustrate some general qualitative behaviors which may be observed. The conclusions of the text only correspond to consequences of the models discussed here, where the parameters are roughly estimated as a function of the evolution of the number of deaths due to COVID-19. They are of course not definitive and are subject to possibly important modifications, due to new information or applications of less simplistic models.