Delays are an important phenomenon arising in a wide variety of real world systems. They occur in biological models because of diffusion effects or as simplifying modeling elements. We propose here to consider delayed stochastic reaction networks. The difficulty here lies in the fact that the state-space of a delayed reaction network is infinite-dimensional, which makes their analysis more involved. We demonstrate here that a particular class of stochastic time-varying delays, namely those that follow a phase-type distribution, can be exactly implemented in terms of a chemical reaction network. Hence, any delay-free network can be augmented to incorporate those delays through the addition of delay-species and delay-reactions. Hence, for this class of stochastic delays, which can be used to approximate any delay distribution arbitrarily accurately, the state-space remains finite-dimensional and, therefore, standard tools developed for standard reaction network still apply. In particular 查看全文>>