Nonperturbative quantum de Sitter universe

@article{Ambjorn2008NonperturbativeQD,
  title={Nonperturbative quantum de Sitter universe},
  author={Jan Ambjorn and Andrzej Goerlich and Jerzy Jurkiewicz and R. Loll},
  journal={Physical Review D},
  year={2008},
  volume={78},
  pages={063544}
}
The dynamical generation of a four-dimensional classical universe from nothing but fundamental quantum excitations at the Planck scale is a long-standing challenge to theoretical physicists. A candidate theory of quantum gravity which achieves this goal without invoking exotic ingredients or excessive fine-tuning is based on the nonperturbative and background-independent technique of causal dynamical triangulations. We demonstrate in detail how in this approach a macroscopic de Sitter universe… 

The self-organized de Sitter universe

We propose a theory of quantum gravity which formulates the quantum theory as a nonperturbative path integral, where each space–time history appears with the weight exp(iSEH), with SEH the

Renormalization in Quantum Theories of Geometry

A hallmark of non-perturbative theories of quantum gravity is the absence of a fixed background geometry, and therefore the absence in a Planckian regime of any notion of length or scale that is

How round is the quantum de Sitter universe?

We investigate the quantum Ricci curvature, which was introduced in earlier work, in full, four-dimensional quantum gravity, formulated nonperturbatively in terms of Causal Dynamical Triangulations

Lattice Quantum Gravity - an Update

We advocate lattice methods as the tool of choice to constructively define a backgroundindependent theory of Lorentzian quantum gravity and explore its physical properties in the Planckian regime.

Scales and Hierachies in Asymptotically Safe Quantum Gravity: A Review

The asymptotic safety program strives for a consistent description of gravity as a non-perturbatively renormalizable quantum field theory. In this framework the gravitational interactions are encoded

Causal dynamical triangulations and the quest for quantum gravity

This work is the only approach to have demonstrated that a classical universe can be generated dynamically from Planckian quantum fluctuations, and allows for the explicit evaluation of expectation values of invariants characterizing the highly nonclassical, short-distance behaviour of spacetime.

Nonperturbative quantum gravity

CDT - an Entropic Theory of Quantum Gravity

In these lectures we describe how a theory of quantum gravity may be constructed in terms of a lattice formulation based on so-called causal dynamical triangulations (CDT). We discuss how the

Spectral geometry as a probe of quantum spacetime

Employing standard results from spectral geometry, we provide strong evidence that in the classical limit the ground state of three-dimensional causal dynamical triangulations is de Sitter spacetime.
...

References

SHOWING 1-10 OF 68 REFERENCES

Planckian birth of a quantum de sitter universe.

We show that the quantum universe emerging from a nonperturbative, Lorentzian sum over geometries can be described with a high accuracy by a four-dimensional de Sitter spacetime. By a scaling

The self-organized de Sitter universe

We propose a theory of quantum gravity which formulates the quantum theory as a nonperturbative path integral, where each space–time history appears with the weight exp(iSEH), with SEH the

Reconstructing the universe

We provide detailed evidence for the claim that nonperturbative quantum gravity, defined through state sums of causal triangulated geometries, possesses a large-scale limit in which the dimension of

Dynamically Triangulating Lorentzian Quantum Gravity

Semiclassical universe from first principles

(2+1)-dimensional quantum gravity as the continuum limit of Causal Dynamical Triangulations

We perform a non-perturbative sum over geometries in a (2+1)-dimensional quantum gravity model given in terms of Causal Dynamical Triangulations. Inspired by the concept of triangulations of product

Nonlocal effective gravitational field equations and the running of Newton's constant G

Non-perturbative studies of quantum gravity have recently suggested the possibility that the strength of gravitational interactions might slowly increase with distance. Here a set of generally
...