Is there any classical model which deals with the birth, life and death of particles? What application could it have?
I am talking about a 'billiard-ball' kind of model, but the kind in which balls keep popping in and out.
What would the configuration space of such a system be like if particle number was not conserved? How would the Hamiltonian evolve with time?
I am not interested in a statistical models.
I can't think of any real world application of such a model. But perhaps there is a mathematical apparatus to deal with the continuous evolution of such systems?