© Paul Coddington, University of Adelaide.

A theory of quantum gravity must explain how the four-dimensional spacetime we inhabit arises. Causal Dynamical Triangulation is an attempt to build four-dimensional spacetime from two-dimensional triangular regions that, when glued together, represent a possible configuration of quantum spacetime fluctuations. Each configuration of triangles, like the one shown above, obeys the postulates of special relativity. The sum of all possible configurations is a spacetime with the same four dimensions in which we live. (Unit: 3)