A Lorentzian Cure for Euclidean Troubles

  title={A Lorentzian Cure for Euclidean Troubles},
  author={Jan Ambjorn and Ananda Dasgupta and Jerzy Jurkiewicz and R Loll},

A hexagon model for 3-d Lorentzian quantum cosmology

We formulate a dynamically triangulated model of three-dimensional Lorentzian quantum gravity whose spatial sections are flat two tori. It is shown that the combinatorics involved in evaluating the

A discrete history of the Lorentzian path integral

In these lecture notes, I describe the motivation behind a recent formulation of a non-perturbative gravitational path integral for Lorentzian (instead of the usual Euclidean) space-times, and give a

Asymptotic safety and quantum gravity amplitudes

Quantum Gravity via Causal Dynamical Triangulations

Causal dynamical triangulations (CDT ) represent a lattice regularization of the sum over spacetime histories, providing us with a nonperturbative formulation of quantum gravity. The ultraviolet

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

Gauge fixing in Causal Dynamical

We relax the definition of the Ambjørn-Loll causal dynamical triangulation model in 1 + 1 dimensions to allow for a varying lapse. We show that, as long as the spatially averaged lapse is constant in

The emergence of spacetime or quantum gravity on your desktop

Is there an approach to quantum gravity which is conceptually simple, relies on very few fundamental physical principles and ingredients, emphasizes geometric (as opposed to algebraic) properties,

Nonperturbative quantum gravity

Detailed Derivation of 1+1 Dimensional Causal Dynamical Triangulations without Preferred Foliation

This paper provides a detailed derivation of one candidate theory of Quantum Gravity: Causal Dynamical Triangulations without preferred foliation in 1+1 dimensions. First, we recover the exact



Nonperturbative lorentzian path integral for gravity

A well-defined regularized path integral is constructed for Lorentzian quantum gravity in terms of dynamically triangulated causal space-times, where the degenerate geometric phases found in dynamicallyTriangulated Euclidean gravity are not present.

Non-perturbative 3d Lorentzian quantum gravity

The phase structure of the Wick-rotated path integral in three dimensions with the aid of computer simulations is investigated, finding a whole range of the gravitational coupling constant k{sub 0} for which the functional integral is dominated by nondegenerate three-dimensional space-times.

Phys. Rev. Lett. Nucl. Phys

  • Phys. Rev. Lett. Nucl. Phys
  • 2000

A.Dasgupta and R.Loll,Nucl.Phys.B606

  • Nucl. Phys. B (Proc. Suppl.)
  • 2001

Phys. Rev

  • Phys. Rev
  • 2001

D i pl om a T hesi s, U ni versi ty of H am burg

    Nucl. Phys. B (Proc. Suppl.)

    • Nucl. Phys. B (Proc. Suppl.)
    • 2001