English
Related papers

Related papers: Comments on area spectra in Loop Quantum Gravity

200 papers

The role of fermionic matter in the spectrum of the area operator is analyzed using the Baez--Krasnov framework for quantum fermions and gravity. The result is that the fermionic contribution to the area of a surface $S$ is equivalent to…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Merced Montesinos , Carlo Rovelli

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

This is the first of two papers which study the behavior of the SU(2) holonomies of loop quantum gravity (LQG), when they are acted upon by a unidirectional, plane gravity wave. Initially, the LQG flux-holonomy variables are treated as…

General Relativity and Quantum Cosmology · Physics 2014-11-12 Donald E. Neville

We give a prescription to define in Loop Quantum Gravity the electric field operator related to the scale factor of an homogeneous and isotropic cosmological space-time. This procedure allows to link the fundamental theory with its…

General Relativity and Quantum Cosmology · Physics 2014-11-21 Francesco Cianfrani , Giovanni Montani

Introducing a new method, we demonstrate how the action of reduced operators can be derived without resorting to a recoupling theory and how they exactly reproduce the results obtained in the standard approach of Quantum Reduced Loop…

General Relativity and Quantum Cosmology · Physics 2020-07-07 Jakub Bilski , Antonino Marciano

The non-factorizing nature of the Hilbert space in Loop Quantum Gravity (LQG) due to gauge invariance requires a generalized definition of entanglement entropy. This work employs the framework of von Neumann algebras to investigate the…

General Relativity and Quantum Cosmology · Physics 2025-11-04 Muxin Han

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 introduce a new operator in Loop Quantum Gravity - the 3D curvature operator - related to the 3-dimensional scalar curvature. The construction is based on Regge Calculus. We define it starting from the classical expression of the Regge…

General Relativity and Quantum Cosmology · Physics 2014-06-25 Emanuele Alesci , Mehdi Assanioussi , Jerzy Lewandowski

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

This article is an extended version of the peer-reviewed publication; Moffat and Wang, J Phys Math 2018, 9:4 DOI: 10.4172/2090-0902.1000289 The article sets out to address a number of issues concerning Loop Quantum Gravity raised by…

General Physics · Physics 2019-03-12 James Moffat , Charles H-T Wang

Several conceptual aspects of quantum gravity are studied on the example of the homogeneous isotropic LQC model. In particular: $(i)$ The proper time of the co-moving observers is showed to be a quantum operator {and} a quantum spacetime…

General Relativity and Quantum Cosmology · Physics 2009-01-27 Wojciech Kaminski , Jerzy Lewandowski , Tomasz Pawlowski

We argue that String Theory and Loop Quantum Gravity can be thought of as describing different regimes of a single unified theory of quantum gravity. LQG can be thought of as providing the pre-geometric exoskeleton out of which macroscopic…

General Relativity and Quantum Cosmology · Physics 2018-01-09 Deepak Vaid

An open issue in loop quantum gravity (LQG) is the introduction of a non-vanishing cosmological constant $\Lambda$. In 3d, Chern-Simons theory provides some guiding lines: $\Lambda$ appears in the quantum deformation of the gauge group. The…

General Relativity and Quantum Cosmology · Physics 2014-12-03 Maïté Dupuis , Florian Girelli

Covariant Loop Quantum Gravity (CLQG) is a tentative background-independent and non-perturbative theory of quantum gravity which has emerged from a number of different research directions. Recently, this theory has been applied to the…

General Relativity and Quantum Cosmology · Physics 2020-01-15 Fabio D'Ambrosio

In this paper we summarize "loop quantum gravity" (LQG) and we show how ideas developed in LQG can solve the black hole singularity problem when applied to a minisuperspace model.

High Energy Physics - Theory · Physics 2007-05-23 Leonardo Modesto

Suppose that there is a quantum operator that describes the horizon area of a black hole. Then what would be the form of the ensuing quantum spectrum? In this regard, it has been conjectured that the characteristic frequencies of the black…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. J. M. Medved

Quantum field theory provides us with the means to calculate scattering amplitudes. In recent years a dramatic new development has lead to great simplification of such calculations. This is based on the discovery of the``amplituhedron'' in…

High Energy Physics - Theory · Physics 2022-08-24 Deepak Vaid , Devadharshini Suresh

We extend the definition of the "flipped" loop-quantum-gravity vertex to the case of a finite Immirzi parameter. We cover the Euclidean as well as the Lorentzian case. We show that the resulting dynamics is defined on a Hilbert space…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Jonathan Engle , Etera Livine , Roberto Pereira , Carlo Rovelli

We present a concrete and explicit construction of a new scalar constraint operator for loop quantum gravity. The operator is defined on the recently introduced space of partially diffeomorphism invariant states, and this space is preserved…

General Relativity and Quantum Cosmology · Physics 2015-08-26 Mehdi Assanioussi , Jerzy Lewandowski , Ilkka Mäkinen

We explore the constraints following from requiring the Area Law in the entanglement entropy in the context of loop quantum gravity. We find a unique solution to the single link wave-function in the large j limit, believed to be appropriate…

General Relativity and Quantum Cosmology · Physics 2018-04-04 Alioscia Hamma , Ling-Yan Hung , Antonino Marciano , Mingyi Zhang