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Related papers: Spectrum of the Volume Operator in Quantum Gravity

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2+1 gravity coupled to a massless scalar field has an initial singularity when the spatial slices are compact. The quantized model is used here to investigate several issues of quantum gravity. The spectrum of the volume operator is studied…

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

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

We develop the first steps towards an analysis of geometry on the quantum spacetime proposed in [1]. The homogeneous elements of the universal differential algebra are naturally identified with operators living in tensor powers of Quantum…

High Energy Physics - Theory · Physics 2015-03-17 Dorothea Bahns , Sergio Doplicher , Klaus Fredenhagen , Gherardo Piacitelli

We introduce a quantum volume operator $K$ in three--dimensional Quantum Gravity by taking into account a symmetrical coupling scheme of three SU(2) angular momenta. The spectrum of $K$ is discrete and defines a complete set of eigenvectors…

General Relativity and Quantum Cosmology · Physics 2009-11-07 G. Carbone , M. Carfora , A. Marzuoli

We present a generalization of the quantum volume operator quantifying the volume in curved three-dimensional discrete geometries. In its standard form, the quantum volume operator is constructed from tetrahedra whose faces are endowed with…

General Relativity and Quantum Cosmology · Physics 2024-10-22 Alexander Hahn , Sebastian Murk , Sukhbinder Singh , Gavin K. Brennen

We derive a closed formula for the matrix elements of the volume operator for canonical Lorentzian quantum gravity in four spacetime dimensions in the continuum in a spin-network basis. We also display a new technique of regularization…

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

A new alternative volume operator is constructed for loop quantum gravity by using the so-called cotriad operators as building blocks. It is shown that the new volume operator shares the same qualitative properties with the standard volume…

General Relativity and Quantum Cosmology · Physics 2016-08-04 Jinsong Yang , Yongge Ma

An angular momentum operator in loop quantum gravity is defined using spherically symmetric states as a non-rotating reference system. It can be diagonalized simultaneously with the area operator and has the familiar spectrum. The operator…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Martin Bojowald

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

A previous paper constructed a kinematic basis for spin networks with planar or cylindrical symmetry and arbitrary polarization. This paper imposes a constraint which limits the gravitational wave to a single polarization. The spectrum of…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Donald E. Neville

This paper constructs a kinematic basis for spin networks with planar or cylindrical symmetry, by exploiting the fact that the basis elements are representations of an O(3) subgroup of O(4). The action of the volume operator on this basis…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Donald E. Neville

The volume operator plays a pivotal role for the quantum dynamics of Loop Quantum Gravity (LQG), both in the full theory and in truncated models adapted to cosmological situations coined Loop Quantum Cosmology (LQC). It is therefore crucial…

General Relativity and Quantum Cosmology · Physics 2008-12-09 C. Flori , T. Thiemann

The symplectic eigenvalues play a significant role in finite mode quantum information theory, and Williamson normal form proves to be a valuable tool in this area. Understanding the symplectic spectrum of a Gaussian Covariance Operator is a…

Spectral Theory · Mathematics 2023-08-01 V. B. Kiran Kumar , Anmary Tonny

This study considers the operator $\hat{T}$ corresponding to the classical spacetime four-volume $\tilde{T}$ (on-shell) of a finite patch of spacetime in the context of Unimodular Loop Quantum Cosmology for the homogeneous and isotropic…

General Relativity and Quantum Cosmology · Physics 2017-01-18 Joseph Bunao

In a previous article we have introduced an operator representing the three-dimensional scalar curvature in loop quantum gravity. In this article we examine the new curvature operator in the setting of quantum-reduced loop gravity. We…

General Relativity and Quantum Cosmology · Physics 2024-12-03 Jerzy Lewandowski , Ilkka Mäkinen

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

We describe a deformation of the observable algebra of quantum gravity in which the loop algebra is extended to framed loops. This allows an alternative nonperturbative quantization which is suitable for describing a phase of quantum…

General Relativity and Quantum Cosmology · Physics 2009-09-25 Seth Major , Lee Smolin

A functional calculus on the space of (generalized) connections was recently introduced without any reference to a background metric. It is used to continue the exploration of the quantum Riemannian geometry. Operators corresponding to…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Abhay Ashtekar , Jerzy Lewandowski

We examine spectrum of the physical volume operator within the non-standard loop quantum cosmology. The spectrum is discrete with equally distant levels defining a quantum of the volume. The discreteness may imply a foamy structure of…

General Relativity and Quantum Cosmology · Physics 2009-10-26 Przemyslaw Malkiewicz , Wlodzimierz Piechocki

In this paper we introduce the n-dimensional hypersurface quantum volume operator by using the n-dimensional holonomy variation formula. Instead of trying to construct the n-dimensional hypersurface volume operator by using the n-1…

General Relativity and Quantum Cosmology · Physics 2018-06-26 Leonid Perlov