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Related papers: Polyhedra in loop quantum gravity

200 papers

A new family of coherent states for all dimensional loop quantum gravity are proposed, which is based on the generalized twisted geometry parametrization of the phase space of $SO(D+1)$ connection theory. We prove that this family of…

General Relativity and Quantum Cosmology · Physics 2022-04-27 Gaoping Long , Xiangdong Zhang , Cong Zhang

In the presence of spacetime boundaries, diffeomorphisms in gravitational theories can become physical and acquire non-vanishing Noether charges. These charges obey an algebra which, within the extended phase-space formalism, faithfully…

High Energy Physics - Theory · Physics 2026-03-24 Ludovic Varrin

Spinor structure and internal symmetries are considered within one theoretical framework based on the generalized spin and abstract Hilbert space. Complex momentum is understood as a generating kernel of the underlying spinor structure. It…

Mathematical Physics · Physics 2015-12-07 V. V. Varlamov

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

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

Spin Foam and Loop approaches to Quantum Gravity reformulate Einstein's theory of relativity in terms of connection variables. The metric properties are encoded in face bivectors/conjugate fluxes that are required to satisfy certain…

General Relativity and Quantum Cosmology · Physics 2019-05-17 Vadim Belov

We study the "improved dynamics" for the treatment of spherically symmetric space-times in loop quantum gravity introduced by Chiou {\em et al.} in analogy with the one that has been constructed by Ashtekar, Pawlowski and Singh for the…

General Relativity and Quantum Cosmology · Physics 2020-10-28 R. Gambini , J. Olmedo , J. Pullin

We use the recently introduced U(N) framework for loop quantum gravity to study the dynamics of spin network states on the simplest class of graphs: two vertices linked with an arbitrary number N of edges. Such graphs represent two regions,…

General Relativity and Quantum Cosmology · Physics 2011-03-28 Enrique F. Borja , Jacobo Diaz-Polo , Iñaki Garay , Etera R. Livine

We investigate the canonical quantization in the framework of N=1 simple supergravity for the case of a very simple gravitational midisuperspace described by Gowdy $T^3$ cosmological models. We consider supersymmetric quantum cosmology in…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Alfredo Macias , Abel Camacho , Jutta Kunz , Claus Laemmerzahl

Given a real-analytic manifold M, a compact connected Lie group G and a principal G-bundle P -> M, there is a canonical `generalized measure' on the space A/G of smooth connections on P modulo gauge transformations. This allows one to…

General Relativity and Quantum Cosmology · Physics 2010-11-01 John C. Baez

Non-perturbative approaches to quantum gravity call for a deep understanding of the emergence of geometry and locality from the quantum state of the gravitational field. Without background geometry, the notion of distance should entirely…

General Relativity and Quantum Cosmology · Physics 2016-03-23 Alexandre Feller , Etera R. Livine

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 explicitly solved the anomaly-free quantum constraints proposed by Tomlin and Varadarajan for the weak Euclidean model of canonical loop quantum gravity, in a large subspace of the model's kinematic Hilbert space which is the space of…

General Relativity and Quantum Cosmology · Physics 2018-07-24 Jerzy Lewandowski , Chun-Yen Lin

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

Spinors have played an essential but enigmatic role in modern physics since their discovery. Now that quantum-gravitational theories have started to become available, the inclusion of a description of spin in the development is natural and…

Mathematical Physics · Physics 2007-05-23 Daniel C. Galehouse

The discrete picture of geometry arising from the loop representation of quantum gravity can be extended by a quantum deformation. The operators for area and volume defined in the q-deformation of the theory are partly diagonalized. The…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Roumen Borissov , Seth Major , Lee Smolin

A new set of twisted geometric variables is introduced to parametrize the holonomy-flux phase space in loop quantum gravity. It is verified that these new geometric variables, after symplectic reduction with respect to the Gauss constraint,…

General Relativity and Quantum Cosmology · Physics 2024-10-15 Gaoping Long , Hongguang Liu , Cong Zhang

In the last 20 years, loop quantum gravity, a background independent approach to unify general relativity and quantum mechanics, has been widely investigated. The aim of loop quantum gravity is to construct a mathematically rigorous,…

General Relativity and Quantum Cosmology · Physics 2007-06-25 Muxin Han

In gravitational theories with boundaries, diffeomorphisms can become physical and acquire a non-vanishing Noether charge. Using the covariant phase space formalism, on shell of the gravitational constraints, the latter localizes on…

High Energy Physics - Theory · Physics 2025-08-11 Luca Ciambelli , Jerzy Kowalski-Glikman , Ludovic Varrin

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