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Related papers: Spectral Analysis of the Volume Operator in Loop Q…

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The purpose of this contribution is to give an introduction to quantum geometry and loop quantum gravity for a wide audience of both physicists and mathematicians. From a physical point of view the emphasis will be on conceptual issues…

Mathematical Physics · Physics 2011-04-11 J. Fernando Barbero G.

We introduce semiclassical methods into the study of the volume spectrum in loop gravity. The classical system behind a 4-valent spinnetwork node is a Euclidean tetrahedron. We investigate the tetrahedral volume dynamics on phase space and…

General Relativity and Quantum Cosmology · Physics 2014-02-19 Eugenio Bianchi , Hal M. Haggard

The dual picture of quantum geometry provided by a spin network state is discussed. From this perspective, we introduce a new operator in Loop Quantum Gravity - the length operator. We describe its quantum geometrical meaning and derive…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Eugenio Bianchi

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

The aim of this letter is to indicate the differences between the Rovelli-Smolin quantum volume operator and other quantum volume operators existing in the literature. The formulas for the operators are written in a unifying notation of the…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Jerzy Lewandowski

The framework of quantum symmetry reduction is applied to loop quantum gravity with respect to transitively acting symmetry groups. This allows to test loop quantum gravity in a large class of minisuperspaces and to investigate its features…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Martin Bojowald

In this work, we propose a generalization of the current most widely used quantum computing hardware metric known as the quantum volume. The quantum volume specifies a family of random test circuits defined such that the logical circuit…

Quantum Physics · Physics 2022-07-18 Keith Miller , Charles Broomfield , Ann Cox , Joe Kinast , Brandon Rodenburg

Results that illuminate the physical interpretation of states of nonperturbative quantum gravity are obtained using the recently introduced loop variables. It is shown that: i) While local operators such as the metric at a point may not be…

High Energy Physics - Theory · Physics 2011-04-20 Abhay Ashtekar , Carlo Rovelli , Lee Smolin

Building on a technical result by Brunnemann and Rideout on the spectrum of the Volume operator in Loop Quantum Gravity, we show that the dimension of the space of the quadrivalent, diffeomorphism invariant states with no zero-volume nodes…

General Relativity and Quantum Cosmology · Physics 2018-08-16 Valerio Astuti , Marios Christodoulou , Carlo Rovelli

We construct the regularised Wheeler-De Witt operator demanding that the algebra of constraints of quantum gravity is anomaly free. We find that for a subset of all wavefunctions being integrals of scalar densities this condition can be…

General Relativity and Quantum Cosmology · Physics 2016-08-15 A. Błaut , J. Kowalski-Glikman

We study and compare the spectra of geometric operators (length and area) in the quantum kinematics of two formulations of three-dimensional Lorentzian loop quantum gravity. In the SU(2) Ashtekar-Barbero framework, the spectra are discrete…

General Relativity and Quantum Cosmology · Physics 2014-05-07 Jibril Ben Achour , Marc Geiller , Karim Noui , Chao Yu

We continue the semiclassical analysis of the Loop Quantum Gravity (LQG) volume operator that was started in the companion paper [23]. In the first paper we prepared the technical tools, in particular the use of complexifier coherent states…

General Relativity and Quantum Cosmology · Physics 2009-04-22 Cecilia Flori

Quantum polyhedra constructed from angular momentum operators are the building blocks of space in its quantum description as advocated by Loop Quantum Gravity. Here we extend previous results on the semiclassical properties of quantum…

General Relativity and Quantum Cosmology · Physics 2014-12-31 John Schliemann

We compute the complete spectrum of the area operator in the loop representation of quantum gravity, using recoupling theory. This result extends previous derivations, which did not include the ``degenerate'' sector, and agrees with the…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Simonetta Frittelli , Luis Lehner , Carlo Rovelli

We analyze combinatorial structures which play a central role in determining spectral properties of the volume operator in loop quantum gravity (LQG). These structures encode geometrical information of the embedding of arbitrary valence…

General Relativity and Quantum Cosmology · Physics 2010-11-22 Johannes Brunnemann , David Rideout

We compute the transition amplitude between coherent quantum-states of geometry peaked on homogeneous isotropic metrics. We use the holomorphic representations of loop quantum gravity and the Kaminski-Kisielowski-Lewandowski generalization…

General Relativity and Quantum Cosmology · Physics 2010-10-27 Eugenio Bianchi , Carlo Rovelli , Francesca Vidotto

We construct an operator that measures the length of a curve in four-dimensional Lorentzian vacuum quantum gravity. We work in a representation in which a $SU(2)$ connection is diagonal and it is therefore surprising that the operator…

General Relativity and Quantum Cosmology · Physics 2009-10-28 T. Thiemann

An alternative expression for the length operator in loop quantum gravity is presented. The operator is background independent, symmetric, positive semidefinite, and well defined on the kinematical Hilbert space. The expression for the…

General Relativity and Quantum Cosmology · Physics 2010-06-15 Yongge Ma , Chopin Soo , Jinsong Yang

We review aspects of quantisation of the 11-dimensional supermembrane world volume theory. We explicitly construct vertex operators for the massless states and study interactions of supermembranes. The open supermembrane and its vertex…

High Energy Physics - Theory · Physics 2011-07-19 Arundhati Dasgupta , Hermann Nicolai , Jan Plefka

One of the celebrated results of Loop Quantum Gravity (LQG) is the discreteness of the spectrum of geometrical operators such as length, area and volume operators. This is an indication that Planck scale geometry in LQG is discontinuous…

General Relativity and Quantum Cosmology · Physics 2009-02-10 Bianca Dittrich , Thomas Thiemann