English
Related papers

Related papers: Taming Thiemann's Hamiltonian constraint in canoni…

200 papers

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

This is the second paper in the series to introduce a graphical method to loop quantum gravity. We employ the graphical method as a powerful tool to calculate the actions of the Euclidean Hamiltonian constraint operator and the so-called…

General Relativity and Quantum Cosmology · Physics 2016-02-25 Jinsong Yang , Yongge Ma

A new symmetric Hamiltonian constraint operator is proposed for loop quantum gravity, which is well defined in the Hilbert space of diffeomorphism invariant states up to non-planar vertices with valence higher than three. It inherits the…

General Relativity and Quantum Cosmology · Physics 2015-12-04 Jinsong Yang , Yongge Ma

We present an explicit computation of matrix elements of the hamiltonian constraint operator in non-perturbative quantum gravity. In particular, we consider the euclidean term of Thiemann's version of the constraint and compute its action…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Roumen Borissov , Roberto De Pietri , Carlo Rovelli

In the model of a fermion field coupled to loop quantum gravity, we consider the Gauss and the Hamiltonian constraints. According to the explicit solutions to the Gauss constraint, the fermion spins and the gravitational spin networks…

General Relativity and Quantum Cosmology · Physics 2022-06-14 Jerzy Lewandowski , Cong Zhang

We discretize the Hamiltonian scalar constraint of three-dimensional Riemannian gravity on a graph of the loop quantum gravity phase space. This Hamiltonian has a clear interpretation in terms of discrete geometries: it computes the…

General Relativity and Quantum Cosmology · Physics 2011-09-12 Valentin Bonzom , Laurent Freidel

This work introduces a new space $\T'_*$ of `vertex-smooth' states for use in the loop approach to quantum gravity. Such states provide a natural domain for Euclidean Hamiltonian constraint operators of the type introduced by Thiemann (and…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Jerzy Lewandowski , Donald Marolf

We study a generalized version of the Hamiltonian constraint operator in nonperturbative loop quantum gravity. The generalization is based on admitting arbitrary irreducible SU(2) representations in the regularization of the operator, in…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Marcus Gaul , Carlo Rovelli

Loop quantum gravity in its Hamiltonian form relies on a connection formulation of the gravitational phase space with three key properties: 1.) a compact gauge group, 2.) real variables, and 3.) canonical Poisson brackets. In conjunction,…

General Relativity and Quantum Cosmology · Physics 2024-12-09 Norbert Bodendorfer , Konstantin Eder , Xiangdong Zhang

In this thesis we consider the problem of dynamics in canonical loop quantum gravity, primarily in the context of deparametrized models, in which a scalar field is taken as a physical time variable for the dynamics of the gravitational…

General Relativity and Quantum Cosmology · Physics 2021-01-01 Ilkka Mäkinen

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

In this article we examine a Hamiltonian constraint operator governing the dynamics of simple quantum states, whose graph consists of a single six-valent vertex, in quantum-reduced loop gravity. To this end, we first derive the action of…

General Relativity and Quantum Cosmology · Physics 2025-05-01 Ilkka Mäkinen

We perform the Hamiltonian constraint analysis for a wide class of gravity theories that are invariant under spatial diffeomorphism. With very general setup, we show that different from the general relativity, the primary and secondary…

General Relativity and Quantum Cosmology · Physics 2014-11-26 Xian Gao

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

One of the hardest problems to tackle in the dynamics of canonical approaches to quantum gravity is that of the Hamiltonian constraint. We investigate said problem in the context of formal geometric quantization. We study the implications…

General Relativity and Quantum Cosmology · Physics 2013-04-19 Vasudev Shyam

We analyze the issue of anomaly-free representations of the constraint algebra in Loop Quantum Gravity (LQG) in the context of a diffeomorphism-invariant gauge theory in three spacetime dimensions. We construct a Hamiltonian constraint…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Adam Henderson , Alok Laddha , Casey Tomlin

Spinfoam models provide a covariant formulation of the dynamics of loop quantum gravity. They are non-perturbatively defined in the group field theory (GFT) framework: the GFT partition function defines the sum of spinfoam transition…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Etera R. Livine , Daniele Oriti , James P. Ryan

The Hamiltonian formulation of scalar-tensor theories of gravity is derived from their Lagrangian formulation by Hamiltonian analysis. The Hamiltonian formalism marks off two sectors of the theories by the coupling parameter $\omega(\phi)$.…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Xiangdong Zhang , Yongge Ma

In [1] we initiated an approach towards quantizing the Hamiltonian constraint in Loop Quantum Gravity (LQG) by requiring that it generates an anomaly-free representation of constraint algebra off-shell. We investigated this issue in the…

General Relativity and Quantum Cosmology · Physics 2014-11-13 Adam Henderson , Alok Laddha , casey Tomlin

Although an important issue in canonical quantization, the problem of representing the constraint algebra in the loop representation of quantum gravity has received little attention. The only explicit computation was performed by Gambini,…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Bernd Bruegmann
‹ Prev 1 2 3 10 Next ›