English
Related papers

Related papers: Weaving a classical geometry with quantum threads

200 papers

In a remarkable paper, T. Koslowski introduced kinematical representations for loop quantum gravity in which there is a non-degenerate spatial background metric present. He also considered their properties, and showed that Gauss and…

General Relativity and Quantum Cosmology · Physics 2010-10-27 Hanno Sahlmann

We compute the two-point correlation function of the area operator for semiclassical states of loop quantum gravity in the limit of large spins. The cases of intrinsic and extrinsic coherent states are considered, along with a new class of…

General Relativity and Quantum Cosmology · Physics 2025-10-29 Filipe H. C. Menezes , Nelson Yokomizo

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 construct in this article a new realization of quantum geometry, which is obtained by quantizing the recently-introduced flux formulation of loop quantum gravity. In this framework, the vacuum is peaked on flat connections, and states…

General Relativity and Quantum Cosmology · Physics 2021-06-18 Benjamin Bahr , Bianca Dittrich , Marc Geiller

We construct a canonical quantization of the two dimensional theory of a parametrized scalar field on noncompact spatial slices. The kinematics is built upon generalized charge-network states which are labelled by smooth embedding…

General Relativity and Quantum Cosmology · Physics 2014-04-09 Sandipan Sengupta

Within the context of loop quantum gravity there are several operators which measure geometry quantities. This work examines two of these operators, volume and angle, to study quantum geometry at a single spin network vertex - ``an atom of…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Seth A. Major , Michael D. Seifert

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

We show that, apart from the usual area operator of non-perturbative quantum gravity, there exists another, closely related, operator that measures areas of surfaces. Both corresponding classical expressions yield the area. Quantum…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Kirill Krasnov

Exactly soluble models can serve as excellent tools to explore conceptual issues in non-perturbative quantum gravity. In perturbative approaches, it is only the two radiative modes of the linearized gravitational field that are quantized.…

General Relativity and Quantum Cosmology · Physics 2022-11-04 Abhay Ashtekar

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 investigate up to which extend the kinematic setting of loop quantum gravity can be fit into a diffeomorphism invariant setting of algebraic QFT generalizing the Haag-Kastler setting of Wightman type QFT. The net of local (Weyl-)algebras…

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

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

This series of lectures gives a simple and self-contained introduction to the non-perturbative and background independent loop approach of canonical quantum gravity. The Hilbert space of kinematical quantum states is constructed and a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Marcus Gaul , Carlo Rovelli

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

Lattice Gauge Theories form a very successful framework for studying nonperturbative gauge field physics, in particular in Quantum Chromodynamics. Recently, their quantum simulation on atomic and solid-state platforms has been discussed,…

Quantum Physics · Physics 2020-03-04 Erez Zohar

Quantum gravity is studied nonperturbatively in the case in which space has a boundary with finite area. A natural set of boundary conditions is studied in the Euclidean signature theory, in which the pullback of the curvature to the…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Lee Smolin

The scaling properties of quantum gravity are discussed by employing a class of proper-time regulators in the functional flow equation for the conformal factor within the formalism of the background field method. Renormalization group…

High Energy Physics - Theory · Physics 2013-12-10 Alfio Bonanno , Filippo Guarnieri

Local observables in (perturbative) quantum gravity are notoriously hard to define, since the gauge symmetry of gravity -- diffeomorphisms -- moves points on the manifold. In particular, this is a problem for backgrounds of high symmetry…

General Relativity and Quantum Cosmology · Physics 2023-11-14 Markus B. Fröb , Albert Much , Kyriakos Papadopoulos

The notion of quantum embedding is considered for two classes of examples: quantum coadjoint orbits in Lie coalgebras and quantum symplectic leaves in spaces with non-Lie permutation relations. A method for constructing irreducible…

Quantum Algebra · Mathematics 2007-05-23 M. V. Karasev

Trying to connect a fundamentally non-commutative spacetime with the conservative perturbative approach to quantum gravity, we are led to the natural question: are non-commutative geometrical effects already present in the regime where…

General Relativity and Quantum Cosmology · Physics 2023-04-20 Markus Fröb , Albert Much , Kyriakos Papadopoulos