Author/Authors :
J. Ambjorn، نويسنده , , A. G?rlich، نويسنده , , J. Jurkiewicz، نويسنده , , R. Loll، نويسنده , , J. Gizbert-Studnicki، نويسنده , , T. Trze?niewski، نويسنده ,
Abstract :
Previous work has shown that the macroscopic structure of the theory of quantum gravity defined by causal dynamical triangulations (CDT) is compatible with that of a de Sitter universe. After emphasizing the strictly nonperturbative nature of this semiclassical limit we present a detailed study of the three-volume data, which allows us to re-confirm the de Sitter structure, exhibit short-distance discretization effects, and make a first detailed investigation of the presence of higher-order curvature terms in the effective action for the scale factor. Technically, we make use of a novel way of fixing the total four-volume in the simulations.