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Related papers: Quantum $R^2$ Gravity in Two Dimensions

200 papers

We derive curvature counterterms in two-dimensional gravity coupled to conformal matter up to infinite order. By construction the higher-order action is equivalent to a finite first-order theory with auxiliary scalar. Due to this…

High Energy Physics - Theory · Physics 2009-10-22 Thomas T. Burwick

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

It is well known that the quantum double structure plays an important role in three dimensional quantum gravity coupled to matter field. In this paper, we show how this algebraic structure emerges in the context of three dimensional…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Karim Noui

Over the last two years, the canonical approach to quantum gravity based on connections and triads has been put on a firm mathematical footing through the development and application of a new functional calculus on the space of gauge…

High Energy Physics - Theory · Physics 2015-06-26 Abhay Ashtekar

A quadratic semiclassical theory, regarding the interaction of gravity with a massive scalar quantum field, is considered in view of the renormalizable energy-momentum tensor in a multi-dimensional curved spacetime. According to it, a…

High Energy Physics - Theory · Physics 2009-11-07 K. Kleidis , A. Kuiroukidis , D. B. Papadopoulos

Quantum-gravity renders the space-time dimension to depend on the size of region; it monotonically increases with the size of region and asymptotically approaches four for large distances. This effect was discovered in numerical simulations…

High Energy Physics - Theory · Physics 2010-02-17 Michael Maziashvili

A new functional calculus, developed recently for a fully non-perturbative treatment of quantum gravity, is used to begin a systematic construction of a quantum theory of geometry. Regulated operators corresponding to areas of 2-surfaces…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Abhay Ashtekar , Jerzy Lewandowski

There ought to exist a reformulation of quantum mechanics which does not refer to an external classical spacetime manifold. Such a reformulation can be achieved using the language of noncommutative differential geometry. A consequence which…

General Relativity and Quantum Cosmology · Physics 2008-11-26 T. P. Singh

More than three decades ago quadratic gravity was found to present a perturbative, renormalizable and asymptotically free theory of quantum gravity. Unfortunately the theory appeared to have problems with a spin-2 ghost. In this essay we…

High Energy Physics - Theory · Physics 2016-11-15 Bob Holdom , Jing Ren

In the framework of the two-form gravity, which is classically equivalent to the Einstein gravity, the one-loop effective potential for the conformal factor of metric is calculated in the finite volume and in the finite temperature by…

High Energy Physics - Theory · Physics 2015-06-26 Miyuki KATSUKI , Shin'ichi NOJIRI , Akio SUGAMOTO

Non-perturbative theories of quantum gravity inevitably include configurations that fail to resemble physically reasonable spacetimes at large scales. Often, these configurations are entropically dominant and pose an obstacle to obtaining…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Graham Brightwell , Joe Henson , Sumati Surya

We consider a discrete model of euclidean quantum gravity in four dimensions based on a summation over random simplicial manifolds. The action used is the Einstein-Hilbert action plus an $R^2$-term. The phase diagram as a function of the…

High Energy Physics - Theory · Physics 2009-10-22 J. Ambjorn , J. Jurkiewicz , C. F. Kristjansen

In the present article, we construct a 2D formulation of quantum gravity in the framework of a deterministic theory. In this context, a Quantum stationary Hamilton-Jacobi equation is derived from the Klein- Gordon equation written in the…

High Energy Physics - Theory · Physics 2007-05-23 T. Djama

In these lectures we review our present understanding of the fractal structure of two-dimensional Euclidean quantum gravity coupled to matter.

High Energy Physics - Theory · Physics 2015-06-17 J. Ambjorn , T. Budd

The two-dimensional theory of gravity describing a graviton-dilaton system is considered. The graviton-dilaton coupling can be fixed such that the quantum theory remains free of the conformal anomaly for any conformal dimension of the…

High Energy Physics - Theory · Physics 2009-10-22 T. T. Burwick , A. H. Chamseddine

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 type introduced previously, we impose an…

High Energy Physics - Theory · Physics 2008-11-26 D. Benedetti , R. Loll , F. Zamponi

We discuss the renormalizability of quantum gravity near two dimensions based on the results obtained by a computation of the BRST-antibracket cohomology in the space of local functionals of the fields and antifields. We justify the…

High Energy Physics - Theory · Physics 2009-10-30 Yoshihisa Kitazawa , Rie Kuriki , Katsumi Shigura

Recent numerical results on the fractal structure of two-dimensional quantum gravity coupled to $c=-2$ matter are reviewed. Analytic derivation of the fractal dimensions based on the Liouville theory and diffusion equation is also…

High Energy Physics - Theory · Physics 2007-05-23 Noboru Kawamoto

The metric of two-dimensional quantum gravity interacting with conformal matter is believed to collapse to a branched polymer metric when the central charge c>1. We show analytically that the spectral dimension of such a branched polymer…

High Energy Physics - Lattice · Physics 2009-10-30 Thordur Jonsson , John F. Wheater

A recently introduced model of dually weighted planar graphs is solved in terms of an elliptic parametrization for some particular collection of planar graphs describing the 2D $R^2$ quantum gravity. Along with the cosmological constant…

High Energy Physics - Theory · Physics 2007-05-23 V. A. Kazakov