Fig. 1: Modelling PMD processes.
From: Implementing quantum dimensionality reduction for non-Markovian stochastic simulation
A PMD process with period N can be exactly modelled with N memory states. At each time step, the process either “survives” (no tick occurs) and the model advances to the next state or undergoes a tick event, and the model moves to a reset state. Due to the N-periodic nature of the conditional statistics, the model also returns to the reset state after surviving N timesteps, leading to the clock-like structure of the model dynamics as depicted.
