Hybrid Semantics of Stochastic Programs with Dynamic Reconfiguration

We begin by reviewing a technique to approximate the dynamics of stochastic programs—written in a stochastic process algebra—by a hybrid system, suitable to capture a mixed discrete/continuous evolution. In a nutshell, the discrete dynamics is kept stochastic while the continuous evolution is given in terms of ODEs, and the overall technique, therefore, naturally associates a Piecewise Deterministic Markov Process with a stochastic program.The specific contribution in this work consists in an increase of the flexibility of the translation scheme, obtained by allowing a dynamic reconfiguration of the degree of discreteness/continuity of the semantics.We also discuss the relationships of this approach with other hybrid simulation strategies for biochemical systems.