Discrete gravity from effective spin foam models

Recently, a new and `effective’ family of spin foam models describing quantum gravity dynamics with discrete area spectrum have been introduced. These models are built directly from the geometrical variables of spacetime and have been shown to be amenable to numerical computations. The simplicity of these models allows to clarify some issues appearing in semi classical analysis of generic spin foam models. I will describe first steps toward testing quantum gravity equations from these models on non-trivial spacetime boundaries. The numerical evaluations reveal a very rich structure of amplitudes and also the expectation values of certain observables results from an interplay between various parameters of the model.