English
Related papers

Related papers: A second-order phase transition in CDT

200 papers

Causal dynamical triangulations (CDT) constitute a background independent, nonperturbative approach to quantum gravity, in which the gravitational path integral is approximated by the weighted sum over causally well-behaving simplicial…

High Energy Physics - Theory · Physics 2011-02-24 T. Trzesniewski

We review some recent results from the causal dynamical triangulation (CDT) approach to quantum gravity. We review recent observations of dimensional reduction at a number of previously undetermined points in the parameter space of CDT, and…

General Relativity and Quantum Cosmology · Physics 2015-10-13 Jan Ambjorn , Daniel Coumbe , Jakub Gizbert-Studnicki , Jerzy Jurkiewicz

We calculate the spectral dimension for a nonperturbative lattice approach to quantum gravity, known as causal dynamical triangulations (CDT), showing that the dimension of spacetime smoothly decreases from approximately 4 on large distance…

High Energy Physics - Theory · Physics 2015-04-21 D. N. Coumbe , J. Jurkiewicz

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…

High Energy Physics - Theory · Physics 2011-05-09 J. Ambjorn , A. Gorlich , J. Jurkiewicz , R. Loll , J. Gizbert-Studnicki , T. Trzesniewski

Motivated by the search for new observables in nonperturbative quantum gravity, we consider Causal Dynamical Triangulations (CDT) in 2+1 dimensions with the spatial topology of a torus. This system is of particular interest, because one can…

High Energy Physics - Theory · Physics 2013-07-11 T. G. Budd , R. Loll

We reinvestigate the recently discovered bifurcation phase transition in Causal Dynamical Triangulations (CDT) and provide further evidence that it is a higher order transition. We also investigate the impact of introducing matter in the…

High Energy Physics - Lattice · Physics 2017-06-21 J. Ambjorn , D. Coumbe , J. Gizbert-Studnicki , A. Gorlich , J. Jurkiewicz

Causal Dynamical Triangulations is a non-perturbative quantum gravity model, defined with a lattice cut-off. The model can be viewed as defined with a proper time but with no reference to any three-dimensional spatial background geometry.…

High Energy Physics - Theory · Physics 2019-06-26 Jan Ambjørn , Zbigniew Drogosz , Jakub Gizbert-Studnicki , Andrzej Görlich , Jerzy Jurkiewicz

We compare the effective action of the scale factor obtained from lattice quantum gravity (in the form of Causal Dynamical Triangulations (CDT)) to the corresponding effective action obtained from the simplest Functional Renormalization…

High Energy Physics - Lattice · Physics 2025-09-26 Jan Ambjørn , Jakub Gizbert-Studnicki , Andrzej Gőrlich , Dániel Németh

We show recent results of the application of spectral analysis in the setting of the Monte Carlo approach to Quantum Gravity known as Causal Dynamical Triangulations (CDT), discussing the behavior of the lowest lying eigenvalues of the…

High Energy Physics - Lattice · Physics 2019-12-25 Giuseppe Clemente , Massimo D'Elia , Alessandro Ferraro

To facilitate the search for a continuum limit of causal dynamical triangulations, Ambjorn, Coumbe, Gizbert-Studnicki, and Jurkiewicz recently reported measurements of the lattice spacing as a function of the bare couplings. Although these…

General Relativity and Quantum Cosmology · Physics 2016-04-08 Joshua H. Cooperman

Asymptotic safety describes a scenario in which general relativity can be quantized as a conventional field theory, despite being nonrenormalizable when expanding it around a fixed background geometry. It is formulated in the framework of…

High Energy Physics - Theory · Physics 2013-02-06 J. Ambjorn , A. Goerlich , J. Jurkiewicz , R. Loll

The role of topology change in a fundamental theory of quantum gravity is still a matter of debate. However, when regarding string theory as two-dimensional quantum gravity, topological fluctuations are essential. Here we present a third…

High Energy Physics - Theory · Physics 2008-02-08 J. Ambjorn , R. Loll , Y. Watabiki , W. Westra , S. Zohren

We extend the 2 dimensional Causal Dynamical Triangulation (CDT) model from the usual model of closed string to the one of open-closed string. The matrix-vector model describing the loop gas model is modified so as to possess the nature of…

High Energy Physics - Theory · Physics 2014-01-16 Hiroshi Kawabe

A major unsolved problem in theoretical physics is to reconcile the classical theory of general relativity with quantum mechanics. These lectures will deal with an attempt to describe quantum gravity as a path integral over geometries known…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Jan Ambjorn , Jerzy Jurkiewicz , Renate Loll

We study matter with central charge $c >1$ coupled to two-dimensional (2d) quantum gravity, here represented as causal dynamical triangulations (CDT). 2d CDT is known to provide a regularization of (Euclidean) 2d Ho\v{r}ava-Lifshitz quantum…

General Relativity and Quantum Cosmology · Physics 2015-04-15 Jan Ambjørn , Andrzej Görlich , Jerzy Jurkiewicz , Hongguang Zhang

The two-dimensional causal dynamical triangulations ($2$d CDT) is a lattice model of quantum geometry. In $2$d CDT, one can deal with the quantum effects analytically and explore the physics through the continuum limit. The continuum theory…

High Energy Physics - Theory · Physics 2025-06-02 Yuki Sato

We introduce a new matrix model that describes Causal Dynamical Triangulations (CDT) in two dimensions. In order to do so, we introduce a new, simpler definition of 2D CDT and show it to be equivalent to the old one. The model makes use of…

High Energy Physics - Theory · Physics 2009-06-28 Dario Benedetti , Joe Henson

3+1 dimensional Causal Dynamical Triangulations (CDT) describe a quantum theory of fluctuating geometries without the introduction of a background geometry. If the topology of space is constrained to be that of a three-dimensional torus we…

High Energy Physics - Theory · Physics 2017-09-13 Jan Ambjørn , Jakub Gizbert-Studnicki , Andrzej Görlich , Kevin Grosvenor , Jerzy Jurkiewicz

We construct a 2-dimensional Causal Dynamical Triangulation (CDT) model from a matrix model which represents the loop gas model of closed string. The target-space index is reinterpreted as time or geodesic distance. We apply stochastic…

High Energy Physics - Theory · Physics 2013-02-07 Hiroshi Kawabe

We provide a hands-on introduction to Monte Carlo simulations in nonperturbative lattice quantum gravity, formulated in terms of Causal Dynamical Triangulations (CDT). We describe explicitly the implementation of Monte Carlo moves and the…

High Energy Physics - Theory · Physics 2023-10-26 Joren Brunekreef , Andrzej Görlich , Renate Loll