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Related papers: Approximating Connections in Loop Quantum Gravity

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Working within the framework of Loop Quantum Gravity (LQG), we construct a set of three operators suitable for identifying coordinate-like quantities on a spin-network configuration. In doing so, we rely on known properties of operators for…

High Energy Physics - Theory · Physics 2018-07-19 Suddhasattwa Brahma , Antonino Marcianò , Michele Ronco

The building blocks of a quantum theory of general relativity are expected to be discrete structures. Loop quantum gravity is formulated using a basis of spin networks (wave functions over oriented graphs with coloured edges), thus…

General Relativity and Quantum Cosmology · Physics 2015-06-17 Jacobo Diaz-Polo , Iñaki Garay

In this review, the fundamental structure of loop quantum gravity is presented pedagogically. Our main aim is to help non-experts to understand the motivations, basic structures, as well as general results. It may also be beneficial to…

General Relativity and Quantum Cosmology · Physics 2011-05-16 Muxin Han , Weiming Huang , Yongge Ma

We investigate the Hilbert space in the Lorentz covariant approach to loop quantum gravity. We restrict ourselves to the space where all area operators are simultaneously diagonalizable, assuming that it exists. In this sector quantum…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Sergei Alexandrov

We investigate the quantum area operator in the loop approach based on the Lorentz covariant hamiltonian formulation of general relativity. We show that there exists a two-parameter family of Lorentz connections giving rise to Wilson lines…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Sergei Alexandrov

The recent developments of the ``connection'' and ``loop'' representations have given the possibility to show that the two representation are equivalent and that it is possible to transform any result from one representation into the other.…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Roberto De Pietri

In loop quantum gravity approach to Planck scale physics, quantum geometry is represented by superposition of the so-called spin network states. In the recent literature, a class of spin networks promising from the perspective of quantum…

General Relativity and Quantum Cosmology · Physics 2021-02-17 Grzegorz Czelusta , Jakub Mielczarek

We show that the principal part of the Dirac Hamiltonian in 3+1 dimensions emerges in a semi-classical approximation from a construction which encodes the kinematics of quantum gravity. The construction is a spectral triple over a…

High Energy Physics - Theory · Physics 2011-03-18 Johannes Aastrup , Jesper M. Grimstrup , Mario Paschke

We propose a naive unification of Electromagnetism and General Relativity based on enlarging the gauge group of Ashtekar's new variables. We construct the connection and loop representations and analyze the space of states. In the loop…

High Energy Physics - Theory · Physics 2009-12-30 R. Gambini , J. Pullin

Utilizing the previously established general formalism for quantum symmetry reduction in the framework of loop quantum gravity the spectrum of the area operator acting on spherically symmetric states in 4 dimensional pure gravity is…

High Energy Physics - Theory · Physics 2009-10-31 M. Bojowald , H. A. Kastrup

Within loop quantum gravity we construct a coarse-grained approximation for the Einstein-Maxwell theory that yields effective Maxwell equations in flat spacetime comprising Planck scale corrections. The corresponding Hamiltonian is defined…

High Energy Physics - Theory · Physics 2009-11-07 Jorge Alfaro , Hugo A. Morales-Técotl , Luis F. Urrutia

The search for a quantum theory of gravity is one of the major challenges facing theoretical physics today. While no complete theory exists, a promising avenue of research is the loop quantum gravity approach. In this approach, quantum…

General Relativity and Quantum Cosmology · Physics 2007-05-23 M. Seifert

We present a straightforward and self-contained introduction to the basics of the loop approach to quantum gravity, and a derivation of what is arguably its key result, namely the spectral analysis of the area operator. We also discuss the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Carlo Rovelli , Peush Upadhya

We propose an unified approach to loop quantum gravity and Fedosov quantization of gravity following the geometry of double spacetime fibrations and their quantum deformations. There are considered pseudo-Riemannian manifolds enabled with…

General Relativity and Quantum Cosmology · Physics 2009-11-21 Sergiu I. Vacaru

We propose a new method of unifying gravity and the Standard Model by introducing a spin-foam model. We realize a unification between an SU(2) Yang-Mills interaction and 3D general relativity by considering a Spin(4) Plebanski action. The…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Stephon Alexander , Antonino Marciano , Ruggero Altair Tacchi

We construct a state in the loop quantum gravity theory with zero cosmological constant, which should correspond to the flat spacetime vacuum solution. This is done by defining the loop transform coefficients of a flat connection…

General Relativity and Quantum Cosmology · Physics 2009-01-16 A. Mikovic

In canonical quantum gravity, the presence of spatial boundaries naturally leads to a boundary quantum states, representing quantum boundary conditions for the bulk fields. As a consequence, quantum states of the bulk geometry needs to be…

General Relativity and Quantum Cosmology · Physics 2021-08-11 Qian Chen , Etera R. Livine

Quantum states of geometry in loop quantum gravity are defined as spin networks, which are graph dressed with SU(2) representations. A spin network edge carries a half-integer spin, representing basic quanta of area, and the standard…

General Relativity and Quantum Cosmology · Physics 2019-09-04 Etera R. Livine

We introduce squeezed vacua in loop quantum gravity, a new overcomplete basis of states that contain prescribable correlations between geometric operators. We study the behavior of long-range correlations and discuss the relevance of these…

General Relativity and Quantum Cosmology · Physics 2016-05-19 Eugenio Bianchi , Jonathan Guglielmon , Lucas Hackl , Nelson Yokomizo

A relation between the non-perturbative loop representation space and the semi-classical loop representation space is studied. A sector of (approximate) states and a sector of operators in the non-perturbative loop representation space are…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Junichi Iwasaki