English

The effective action in 4-dim CDT. The transfer matrix approach

High Energy Physics - Theory 2015-04-02 v2 General Relativity and Quantum Cosmology High Energy Physics - Lattice

Abstract

We measure the effective action in all three phases of 4-dimensional Causal Dynamical Triangulations (CDT) using the transfer matrix method. The transfer matrix is parametrized by the total 3-volume of the CDT universe at a given (discrete) time. We present a simple effective model based on the transfer matrix measured in the de Sitter phase. It allows us to reconstruct the results of full CDT in this phase. We argue that the transfer matrix method is valid not only inside the de Sitter phase ('C') but also in the other two phases. A parametrization of the measured transfer matrix / effective action in the 'A' and 'B' phases is proposed and the relation to phase transitions is explained. We discover a potentially new 'bifurcation' phase separating the de Sitter phase ('C') and the 'collapsed' phase ('B').

Cite

@article{arxiv.1403.5940,
  title  = {The effective action in 4-dim CDT. The transfer matrix approach},
  author = {Jan Ambjorn and Jakub Gizbert-Studnicki and Andrzej Görlich and Jerzy Jurkiewicz},
  journal= {arXiv preprint arXiv:1403.5940},
  year   = {2015}
}

Comments

33 pages, 24 figures

R2 v1 2026-06-22T03:32:48.299Z