• processi stocastici
• teoria di campo.
• Fisica Matematica

The aim of the project is to devise a general method to characterise the stationary state in finite systems, subjected to particular microscopic, local dynamics.
Specifically, we have investigated, by means of field-theoretic techniques, the non-universal properties of a single species reaction-diffusion system.
To make the stochastic process accessible to field-theoretic methods we have taken the Doi-Peliti formalism, which provides an exact description of the process in terms of a field theory. Furthermore, alongside the analytical approach we have investigated the system by means of Monte Carlo simulations in C.
Field-theoretical techniques, usually used for the computation of universal quantities at criticality, have been employed for the characterisation of non-universal properties of the stationary state.
A general definition of the stationary state in terms of a field theory has been given
and a strong agreement between analytical results and Monte Carlo simulations has been found, near and away from the critical domain.