  The structure of simplicial manifolds in a model of Causal Dynamical
Triangulations in 3+1 dimensions with the spatial topology of a 3-torus is
analyzed with the help of topological observables, such as loops with nonzero
winding numbers and coordinates based on scalar fields with jumps at the
boundaries of the elementary cell of the torus. The results are given an
interpretation and used in the measurements of a more local observable that is
the quantum Ricci curvature. We moreover analyze the influence of scalar matter
fields on the geometry of CDT spacetimes.
