Causal Set Phenomenology in Friedmann-Robertson-Walker Spacetime

The causal set approach to quantum gravity states that spacetime is not a continuous Lorenztian manifold but a causal set composed of discrete spacetime elements together with their causal relations. It is argued that using only causality and discreteness, one can recover a more fundamental theory of gravitation with interesting qualities. Though the theory is incomplete, some phenomenological models have been developed, one of which is discussed here. Since discrete spacetime is locally finite, there are a finite number of paths a free massive particle can take. It will be forced to deviate from its classical geodesic path through a process known as swerving. This model was been developed for Minkowski spacetime, and in this paper we attempt to generalise the model to Friedmann-Robertson-Walker spacetime which is used in cosmology.