Causal dynamical triangulation

Summary

Causal dynamical triangulation (CDT) is an approach to quantum gravity. It defines the gravitational path integral as a sum over spacetimes built from flat simplices. The simplices are glued so that the result has a global notion of time. It was developed by Jan Ambjørn, Jerzy Jurkiewicz and Renate Loll from the late 1990s. The causal gluing rule distinguishes it from earlier Euclidean dynamical triangulations. Computer simulations in four dimensions show an extended four-dimensional universe in one of its phases.