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Related papers: Fractal Structure of Loop Quantum Gravity

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When gauge field theory coherent states for loop quantum gravity (LQG) were introduced, an optimized semiclassical proper length emerged, corresponding to the edge length $\epsilon$ of a graph embedded in a given classical geometry. Here…

General Relativity and Quantum Cosmology · Physics 2014-02-20 Paul G. N. de Vegvar

We study the fractal structure of space-time of two-dimensional quantum gravity coupled to c=-2 conformal matter by means of computer simulations. We find that the intrinsic Hausdorff dimension d_H = 3.58 +/- 0.04. This result supports the…

High Energy Physics - Lattice · Physics 2009-10-30 J. Ambjorn , K. N. Anagnostopoulos , T. Ichihara , L. Jensen , N. Kawamoto , Y. Watabiki , K. Yotsuji

This paper is concerned with computing the spectral dimension of 2d-Liouville quantum gravity. As a warm-up, we first treat the simple case of boundary Liouville quantum gravity. We prove that the spectral dimension is 1 via an exact…

Probability · Mathematics 2015-06-15 Rémi Rhodes , Vincent Vargas

Quantum field theory (QFT) on fractal spacetimes is a program aiming at quantizing the gravitational interaction consistently at all energy scales thanks to an intrinsically or dynamically induced multiscale or multifractal-like spacetime…

High Energy Physics - Theory · Physics 2026-03-26 Fabio Briscese , Gianluca Calcagni

The problem of finding the quantum theory of the gravitational field, and thus understanding what is quantum spacetime, is still open. One of the most active of the current approaches is loop quantum gravity. Loop quantum gravity is a…

General Relativity and Quantum Cosmology · Physics 2016-10-19 Carlo Rovelli

We measure the spectral dimension of universes emerging from nonperturbative quantum gravity, defined through state sums of causal triangulated geometries. While four-dimensional on large scales, the quantum universe appears two-dimensional…

High Energy Physics - Theory · Physics 2010-04-06 J. Ambjorn , J. Jurkiewicz , R. Loll

We propose an approach which, by combining insights from Loop Quantum Gravity (LQG), Topos theory, Non-commutative Geometry \`a la Connes, and spacetime relationalism, provides fertile ground for the search of an adequate spacetime picture…

General Relativity and Quantum Cosmology · Physics 2021-03-12 Alejandro Ascárate

We study a c=-2 conformal field theory coupled to two-dimensional quantum gravity by means of dynamical triangulations. We define the geodesic distance r on the triangulated surface with N triangles, and show that dim[r^{d_H}]= dim[N],…

High Energy Physics - Lattice · Physics 2019-08-15 J. Ambjorn , K. N. Anagnostopoulos , T. Ichihara , L. Jensen , N. Kawamoto , Y. Watabiki , K. Yotsuji

We show that the spectral dimension d_s of two-dimensional quantum gravity coupled to Gaussian fields is two for all values of the central charge c <= 1. The same arguments provide a simple proof of the known result d_s= 4/3 for branched…

High Energy Physics - Theory · Physics 2010-02-03 J. Ambjorn , D. Boulatov , J. L. Nielsen , J. Rolf , Y. Watabiki

Loop Quantum Gravity (LQG) is one of the leading approaches to unify quantum physics and General Relativity (GR). The Hilbert space of LQG is spanned by spin-networks which describe the local geometry of quantum space-time. Simulation of…

General Relativity and Quantum Cosmology · Physics 2021-12-21 Swapnil Nitin Shah

We couple c=-2 matter to 2-dimensional gravity within the framework of dynamical triangulations. We use a very fast algorithm, special to the c=-2 case, in order to test scaling of correlation functions defined in terms of geodesic distance…

High Energy Physics - Lattice · Physics 2009-10-30 J. Ambjorn , K. N. Anagnostopoulos , T. Ichihara , L. Jensen , N. Kawamoto , Y. Watabiki , K. Yotsuji

We describe a theory of quantum gravity which is based on the assumption that the spacetime structure at small distances is given by a piecewise linear (PL) 4-manifold corresponding to a triangulation of a smooth 4-manifold. The fundamental…

General Relativity and Quantum Cosmology · Physics 2018-07-18 Aleksandar Mikovic , Marko Vojinovic

Loop Quantum Gravity (LQG) is a promising approach to quantum gravity, in particular because it is based on a rigorous quantization of the kinematics of gravity. A difficult and still open problem in the LQG program is the construction of…

General Relativity and Quantum Cosmology · Physics 2013-03-01 Tim Koslowski

A manifestly Lorentz-covariant formulation of Loop Quantum Gravity (LQG) is given in terms of finite-dimensional representations of the Lorentz group. The formulation accounts for discrete symmetries, such as parity and time-reversal, and…

General Relativity and Quantum Cosmology · Physics 2021-12-08 Francesco Cianfrani

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 spacetime is four and the dynamics of the…

High Energy Physics - Theory · Physics 2010-04-06 J. Ambjorn , J. Jurkiewicz , R. Loll

We compute the intrinsic Hausdorff dimension of spacetime at the infrared fixed point of the quantum conformal factor in 4D gravity. The fractal dimension is defined by the appropriate covariant diffusion equation in four dimensions and is…

High Energy Physics - Theory · Physics 2009-10-31 Ignatios Antoniadis , Pawel O. Mazur , Emil Mottola

A semifinite spectral triple for an algebra canonically associated to canonical quantum gravity is constructed. The algebra is generated by based loops in a triangulation and its barycentric subdivisions. The underlying space can be seen as…

High Energy Physics - Theory · Physics 2009-04-08 Johannes Aastrup , Jesper M. Grimstrup , Ryszard Nest

Studies of the effective regime of loop quantum gravity (LQG) revealed that, in the limit of Planckian curvature scales, spacetime may undergo a transition from the Lorentzian to Euclidean signature. This effect is a consequence of quantum…

High Energy Physics - Theory · Physics 2017-07-21 Jakub Mielczarek , Tomasz Trześniewski

We study the fractal structure of the surface in two-dimensional quantum Regge calculus by performing Monte Carlo simulation with up to 200,000 triangles. The result can be compared with the universal scaling function obtained analytically…

High Energy Physics - Lattice · Physics 2009-10-22 Jun Nishimura , Masaki Oshikawa

We study the spectrum of the length and area operators in Lorentzian loop quantum gravity, in 2+1 spacetime dimensions. We find that the spectrum of spacelike intervals is continuous, whereas the spectrum of timelike intervals is discrete.…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Laurent Freidel , Etera R. Livine , Carlo Rovelli