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Related papers: Baby universes in 2d quantum gravity

200 papers

We study 2D quantum gravity on spherical topologies using the Regge calculus approach. Our goal is to shed new light upon the validity of the Regge approach to quantum gravity, which has recently been questioned in the literature. We…

High Energy Physics - Lattice · Physics 2009-10-28 Christian Holm , Wolfhard Janke

We consider a class of spin systems on randomly triangulated surfaces as discrete approximations to conformal matter fields coupled to 2d gravity. On the basis of certain universality assumptions we argue that at critical points with…

High Energy Physics - Theory · Physics 2009-10-28 B. Durhuus

Topological defects in the framework of effective quantum gravity model are investigated, based on the hypothesis of an effective fractal dimension of the universe. This is done by using Caputo fractional derivatives to determine the…

General Relativity and Quantum Cosmology · Physics 2023-12-29 Sebastien Fumeron , Malte Henkel , Alexander Lopez

A potentially powerful approach to quantum gravity has been developed over the last few years under the name of Causal Dynamical Triangulations. Numerical simulations have given very interesting results in the cases of two, three and four…

General Relativity and Quantum Cosmology · Physics 2007-09-05 Dario Benedetti

We study 2D quantum gravity on spherical topologies employing the Regge calculus approach with the dl/l measure. Instead of the normally used fixed non-regular triangulation we study random triangulations which are generated by the standard…

High Energy Physics - Lattice · Physics 2009-10-31 Christian Holm , Wolfhard Janke

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

Causal dynamical triangulations (CDT) can be used as a regularization of quantum gravity. In two dimensions the theory can be solved anlytically, even before the cut-off is removed and one can study in detail how to take the continuum…

High Energy Physics - Theory · Physics 2014-11-20 J. Ambjorn , R. Loll , Y. Watabiki , W. Westra , S. Zohren

A classical two dimensional theory of gravity which has a number of interesting features (including a Newtonian limit, black holes and gravitational collapse) is quantized using conformal field theoretic techniques. The critical dimension…

High Energy Physics - Theory · Physics 2009-10-22 R. B. Mann

We study quantum gravitational effect on a two-dimensional open universe with one particle by means of a string bit model. We find that matter is necessarily homogeneously distributed if the influence of the particle on the size of the…

High Energy Physics - Theory · Physics 2009-11-10 C. -W. H. lee , R. B. Mann

The main results for the two-dimensional quantum gravity, conjectured from the matrix model or integrable approach, are presented in the form to be compared with the world-sheet or Liouville approach. In spherical limit the integrable side…

High Energy Physics - Theory · Physics 2009-07-22 A. Marshakov

String theory provides the only consistent framework so far that unifies all interactions including gravity. We discuss gravity and cosmology in string theory. Conventional notions from general relativity like geometry, topology etc. are…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Elias Kiritsis , Costas Kounnas

Despite their diversity, many of the most prominent candidate theories of quantum gravity share the property to be effectively lower-dimensional at small scales. In particular, dimension two plays a fundamental role in the finiteness of…

High Energy Physics - Theory · Physics 2015-03-17 Gianluca Calcagni

Most of the approaches to the construction of a theory of quantum gravity share some principles which do not have specific experimental support up to date. Two of these principles are relevant for our discussion: (i) the gravitational field…

General Relativity and Quantum Cosmology · Physics 2015-02-18 Raúl Carballo-Rubio , Carlos Barceló , Luis J. Garay

The 2-point function is the natural object in quantum gravity for extracting critical behavior: The exponential fall off of the 2-point function with geodesic distance determines the fractal dimension $d_H$ of space-time. The integral of…

High Energy Physics - Theory · Physics 2016-09-06 J. Ambjorn , Y. Watabiki

We propose a new type of gauge in two-dimensional quantum gravity. We investigate pure gravity in this gauge, and find that the system reduces to quantum mechanics of loop length $l$. Furthermore, we rederive the $c\!=\!0$ string field…

High Energy Physics - Theory · Physics 2009-10-22 M. Fukuma , N. Ishibashi , H. Kawai , M. Ninomiya

The geometry of 4D simplicial quantum gravity with a U(1) gauge field is studied numerically. The phase diagram shows a continuous transition when gravity is coupled with a U(1) gauge field. At the critical point measurements of the…

High Energy Physics - Lattice · Physics 2009-10-31 H. S. Egawa , S. Horata , T. Yukawa

I discuss the impact of gauge-gravity duality on our understanding of two classes of systems: conformal quantum matter and compressible quantum matter. The first conformal class includes systems, such as the boson Hubbard model in two…

Strongly Correlated Electrons · Physics 2012-04-12 Subir Sachdev

In type IIB string theory, we consider fractional D3-branes in the orbifold background dual to four-dimensional N=2 supersymmetric Yang-Mills theory. We find the gravitational dual description of the generation of a non-trivial field theory…

High Energy Physics - Theory · Physics 2008-11-26 Paolo Merlatti

We study primordial perturbations generated from quantum fluctuations of an inflaton based on the formalism of stochastic gravity. Integrating out the degree of freedom of the inflaton field, we analyze the time evolution of the correlation…

High Energy Physics - Theory · Physics 2008-11-26 Yuko Urakawa , Kei-ichi Maeda

We discuss scaling relations in four dimensional simplicial quantum gravity. Using numerical results obtained with a new algorithm called ``baby universe surgery'' we study the critical region of the theory. The position of the phase…

High Energy Physics - Theory · Physics 2009-07-09 Jan Ambjorn , Jerzy Jurkiewicz