English
Related papers

Related papers: Approximating Connections in Loop Quantum Gravity

200 papers

We show that the path integral for the three-dimensional SU(2) BF theory with a Wilson loop or a spin network function inserted can be understood as the Rovelli-Smolin loop transform of a wavefunction in the Ashtekar connection…

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

Spin network states are a powerful tool for constructing the $SU(2)$ gauge theories on a graph. In loop quantum gravity (LQG), they have yielded many promising predictions, although progress has been limited by the computational challenge…

General Relativity and Quantum Cosmology · Physics 2023-04-10 Grzegorz Czelusta , Jakub Mielczarek

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

An exposition of Vassiliev invariants is given in terms of the simplest approach to the functional integral construction of link invariants from Chern-Simons theory. This approach gives the top row evaluations of Vassiliev invariants for…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Louis H. Kauffman

In three dimensional ${\cal N}=4$ Chern-Simons-matter theories two independent fermionic Wilson loop operators can be defined, which preserve half of the supersymmetry charges and are cohomologically equivalent at classical level. We…

High Energy Physics - Theory · Physics 2016-09-21 Marco S. Bianchi , Luca Griguolo , Matias Leoni , Andrea Mauri , Silvia Penati , Domenico Seminara

We study the operator that corresponds to the measurement of volume, in non-perturbative quantum gravity, and we compute its spectrum. The operator is constructed in the loop representation, via a regularization procedure; it is finite,…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Carlo Rovelli , Lee Smolin

These notes are a didactic overview of the non perturbative and background independent approach to a quantum theory of gravity known as loop quantum gravity. The definition of real connection variables for general relativity, used as a…

General Relativity and Quantum Cosmology · Physics 2009-09-29 Alejandro Perez

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 introduce a new technique for dealing with the matrix elements of the Hamiltonian operator in loop quantum gravity, based on the use of intertwiners projected on coherent states of angular momentum. We give explicit expressions for the…

General Relativity and Quantum Cosmology · Physics 2016-10-26 Emanuele Alesci , Jerzy Lewandowski , Ilkka Mäkinen

In this article we summarize and describe the recently found transforms for theories of connections modulo gauge transformations associated with compact gauge groups. Specifically, we put into a coherent picture the so-called loop…

General Relativity and Quantum Cosmology · Physics 2011-04-15 Thomas 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

A coarse-graining of spin networks is expressed in terms of partial tracing, thus allowing to use tools of quantum information theory. This is illustrated by the analysis of a simple black hole model, where the logarithmic correction of the…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Daniel R. Terno

Loop quantum gravity is a physical theory which aims at unifying general relativity and quantum mechanics. It takes general relativity very seriously and modifies it via a quantisation. General relativity describes gravity in terms of…

General Relativity and Quantum Cosmology · Physics 2022-02-02 J. Manuel García-Islas

A spin network is a generalization of a knot or link: a graph embedded in space, with edges labelled by representations of a Lie group, and vertices labelled by intertwining operators. Such objects play an important role in 3-dimensional…

General Relativity and Quantum Cosmology · Physics 2010-07-27 John C. Baez

We construct a quantum kinematics for asymptotically flat spacetimes based on the Koslowski-Sahlmann (KS) representation. The KS representation is a generalization of the representation underlying Loop Quantum Gravity (LQG) which supports,…

General Relativity and Quantum Cosmology · Physics 2015-06-17 Miguel Campiglia , Madhavan Varadarajan

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 define a simplified version of Regge quantum gravity where the link lengths can take on only two possible values, both always compatible with the triangle inequalities. This is therefore equivalent to a model of Ising spins living on the…

High Energy Physics - Lattice · Physics 2009-10-22 Tom Fleming , Mark Gross , Ray Renken

We investigate some properties of geometric operators in canonical quantum gravity in the connection approach \`a la Ashtekar, which are associated with volume, area and length of spatial regions. We motivate the construction of analogous…

General Relativity and Quantum Cosmology · Physics 2009-10-28 R. Loll

For quantum lattice systems with local interactions, the Lieb-Robinson bound acts as an alternative for the strict causality of relativistic systems and allows to prove many interesting results, in particular when the energy spectrum…

A Josephson junction made of a generic magnetic material sandwiched between two conventional superconductors is studied in the ballistic semi-classic limit. The spectrum of Andreev bound states is obtained from the single-valuedness of a…

Superconductivity · Physics 2016-06-10 François Konschelle , F. Sebastián Bergeret , Ilya V. Tokatly