English
Related papers

Related papers: On propagation in Loop Quantum Gravity

200 papers

If one replaces the constraints of the Ashtekar-Barbero $SU(2)$ gauge theory formulation of Euclidean gravity by their $U(1)^3$ version, one arrives at a consistent model which captures significant structure of its $SU(2)$ version. In…

General Relativity and Quantum Cosmology · Physics 2021-12-21 Sepideh Bakhoda , Thomas Thiemann

We study a type of geometric theory with a non-dynamical one-form field. Its dynamical variables are an $su(2)$ gauge field and a triad of $su(2)$ valued one-forms. Hamiltonian decomposition reveals that the theory has a true Hamiltonian,…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Jack Gegenberg , Viqar Husain

In the Hamiltonian formulation, Quantum Field Theory calculations scale exponentially with spatial volume, making real-time simulations intractable on classical computers and motivating quantum computation approaches. In Hamiltonian…

High Energy Physics - Lattice · Physics 2025-11-03 Zong-Gang Mou , Bipasha Chakraborty

The G -->0 limit of Euclidean gravity introduced by Smolin is described by a generally covariant U(1)xU(1)xU(1) gauge theory. The Poisson bracket algebra of its Hamiltonian and diffeomorphism constraints is isomorphic to that of gravity.…

General Relativity and Quantum Cosmology · Physics 2015-01-30 Casey Tomlin , Madhavan Varadarajan

Spin networks in loop quantum gravity provide a kinematical picture of quantum geometry but lack a natural mechanism for dynamical Dirac-type evolution, while the Wheeler--DeWitt equation typically enters only as an imposed constraint. We…

General Relativity and Quantum Cosmology · Physics 2025-11-04 Partha Nandi , Partha Ghose , Francesco Petruccione

We focus on three-dimensional QRLG with the purpose of shedding light on the link between reduced LQG and LQC in four space-time dimensions. Considering homogeneous three-dimensional LQG, the theory simplifies to QRLG. We then implement…

General Relativity and Quantum Cosmology · Physics 2017-07-06 Jakub Bilski , Antonino Marciano

In this paper, I investigate the quantisation of length in euclidean quantum gravity in three dimensions. The starting point is the classical hamiltonian formalism in a cylinder of finite radius. At this finite boundary, a counter term is…

General Relativity and Quantum Cosmology · Physics 2018-04-06 Wolfgang Wieland

This paper deals with several technical issues of non-perturbative four-dimensional Lorentzian canonical quantum gravity in the continuum that arose in connection with the recently constructed Wheeler-DeWitt quantum constraint operator. 1)…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Thomas Thiemann

In loop quantum gravity (LQG), states of the gravitational field are represented by labeled graphs called spin networks. Their dynamics can be described by a Hamiltonian constraint, { which acts on the spin network states modifying both…

General Relativity and Quantum Cosmology · Physics 2025-11-27 Thiago L. M. Guedes , Guillermo A. Mena Marugán , Francesca Vidotto , Markus Müller

A manifestly Lorentz-covariant formulation of Loop Quantum Gravity (LQG) is given in terms of finite-dimensional representations of the Lorentz group. The formulation accounts for discrete symmetries, such as parity and time-reversal, and…

General Relativity and Quantum Cosmology · Physics 2021-12-08 Francesco Cianfrani

We propose a new, discretized model for the study of 3+1-dimensional canonical quantum gravity, based on the classical $SL(2,\C)$-connection formulation. The discretization takes place on a topological $N^3$- lattice with periodic boundary…

General Relativity and Quantum Cosmology · Physics 2010-11-01 R. Loll

After short historical overview we describe the difficulties with application of standard QFT methods in quantum gravity (QG). The incompatibility of QG with the use of classical continuous space-time required conceptually new approach. We…

High Energy Physics - Theory · Physics 2014-12-01 Jerzy Lukierski

Lattice gauge theories in varying dimensions, lattice volumes, and truncations offer a rich family of targets for Hamiltonian simulation on quantum devices. In return, formulating quantum simulations can provide new ways of thinking about…

A crucial problem in quantum cosmology is a careful analysis of the one-loop semiclassical approximation for the wave function of the universe, after an appropriate choice of mixed boundary conditions. The results for Euclidean quantum…

High Energy Physics - Theory · Physics 2007-05-23 Giampiero Esposito , Alexander Yu. Kamenshchik

We develop in a companion article the kinematics of three-dimensional loop quantum gravity in Euclidean signature and with a negative cosmological constant, focusing in particular on the spinorial representation which is well-known at zero…

General Relativity and Quantum Cosmology · Physics 2022-10-05 Valentin Bonzom , Maïté Dupuis , Qiaoyin Pan

The utility of the U(1)$^3$ model as a test laboratory for quantum gravity has recently been emphasized in a recent series of papers due to Varadarajan et al. The simplification from SU(2) to U(1)$^3$ can be performed simply by hand within…

General Relativity and Quantum Cosmology · Physics 2021-12-21 Sepideh Bakhoda , Thomas Thiemann

Recently the Master Constraint Programme (MCP) for Loop Quantum Gravity (LQG) was launched which replaces the infinite number of Hamiltonian constraints by a single Master constraint. The MCP is designed to overcome the complications…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Thomas Thiemann

Different versions of consistent canonical realizations of hypersurface deformations of spherically symmetric space-times have been derived in models of loop quantum gravity, modifying the classical dynamics and sometimes also the structure…

General Relativity and Quantum Cosmology · Physics 2020-02-13 Martin Bojowald , Suddhasattwa Brahma , Ding Ding , Michele Ronco

The G-->0 limit of Euclidean gravity introduced by Smolin is described by a generally covariant U(1)xU(1)xU(1) gauge theory. In an earlier paper, Tomlin and Varadarajan constructed the quantum Hamiltonian constraint of density weight 4/3…

General Relativity and Quantum Cosmology · Physics 2015-01-30 Madhavan Varadarajan

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