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In a previous paper we formulated axisymmetric general relativity in terms of real Ashtekar--Barbero variables. Here we proceed to quantize the theory. We are able to implement Thiemann's version of the Hamiltonian constraint. We discuss…

General Relativity and Quantum Cosmology · Physics 2020-06-17 Rodolfo Gambini , Esteban Mato , Jorge Pullin

There is a gap that has been left open since the formulation of general relativity in terms of Ashtekar's new variables namely the treatment of asymptotically flat field configurations that are general enough to be able to define the…

General Relativity and Quantum Cosmology · Physics 2010-04-06 T. Thiemann

One of the virtues of the Ashtekar variables is the simplification of the initial value constraints for gravity. In the case of self-dual variables this entails a complexification of the phase space which comes at the expense of having to…

General Relativity and Quantum Cosmology · Physics 2013-11-25 Eyo Eyo Ita

There is a gap that has been left open since the formulation of general relativity in terms of Ashtekar's new variables namely the treatment of asymptotically flat field configurations that are general enough to be able to define the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 T. Thiemann

As basic variables in general relativity (GR) are chosen antisymmetric connection and bivectors - bilinear in tetrad area tensors subject to appropriate (bilinear) constraints. In canonical formalism we get theory with polinomial…

General Relativity and Quantum Cosmology · Physics 2007-05-23 V. Khatsymovsky

We consider the quantization of gravity as an SL(2,C) gauge theory in terms of Ashtekar's selfdual variables and reality conditions for the spatial metric (RCI) and its evolution (RCII). We start from a holomorphic phase space formulation.…

General Relativity and Quantum Cosmology · Physics 2023-10-31 Hanno Sahlmann , Robert Seeger

This paper presents an improvement to the four-dimensional spinfoam model with cosmological constant ($\Lambda$-SF model) in loop quantum gravity. The original $\Lambda$-SF model, defined via ${\rm SL}(2,\mathbb{C})$ Chern-Simons theory on…

General Relativity and Quantum Cosmology · Physics 2025-06-03 Muxin Han , Qiaoyin Pan

The Lagrangian formulation of classical field theories and in particular general relativity leads to a coordinate-free, fully covariant analysis of these constrained systems. This paper applies multisymplectic techniques to obtain the…

General Relativity and Quantum Cosmology · Physics 2010-11-01 G. Esposito , C. Stornaiolo , G. Gionti

A Lorentz and general co-ordinate co-variant form of canonical gravity, using Ashtekar's variables, is investigated. A co-variant treatment due to Crnkovic and Witten is used, in which a point in phase space represents a solution of the…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Brian P. Dolan , Kevin P. Haugh

In order to test the canonical quantization programme for general relativity we introduce a reduced model for a real sector of complexified Ashtekar gravity which captures important properties of the full theory. While it does not…

General Relativity and Quantum Cosmology · Physics 2010-04-06 T. Thiemann

The Immirzi parameter is promoted to be a scalar field and the Hamiltonian analysis of the corresponding dynamical system is performed in the presence of gravity. We identified some SU(2) connections, generalizing Ashtekar-Barbero…

General Relativity and Quantum Cosmology · Physics 2016-09-14 Flavio Bombacigno , Francesco Cianfrani , Giovanni Montani

We quantize the exterior of spherically symmetric vacuum space-times using a midi-superspace reduction within the Ashtekar new variables. Through a partial gauge fixing we eliminate the diffeomorphism constraint and are left with a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Miguel Campiglia , Rodolfo Gambini , Jorge Pullin

In this paper it is implemented how to make compatible the boundary conditions and the gauge fixing conditions for complex general relativity written in terms of Ashtekar variables using the Henneaux-Teitelboim-Vergara approach. Moreover,…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Merced Montesinos , Jose David Vergara

This is a summary of a talk delivered at the workshop ``Quantum gravity in the Southern Cone II''. We present a very brief review of current results on canonical quantization of general relativity using Ashtekar's variables and loop…

General Relativity and Quantum Cosmology · Physics 2011-04-15 Jorge Pullin

In this paper we revisit the nonmanifestly Lorentz-covariant canonical analysis of the Holst action with a cosmological constant. We take a viewpoint close to that of F. Cianfrani and G. Montani [Phys. Rev. Lett. 102, 091301 (2009)] and…

General Relativity and Quantum Cosmology · Physics 2019-03-25 Merced Montesinos , Jorge Romero , Mariano Celada

We investigate the quantum geometry of $2d$ surface $S$ bounding the Cauchy slices of 4d gravitational system. We investigate in detail and for the first time the symplectic current that naturally arises boundary term in the first order…

General Relativity and Quantum Cosmology · Physics 2015-07-10 Laurent Freidel , Alejandro Perez

A new form of the dynamical equations of vacuum general relativity is proposed. This form involves the canonical Hamiltonian structure but non canonical variables. The new field variables are the electric field $E^{a}{}_{i}$ and the…

General Relativity and Quantum Cosmology · Physics 2008-02-07 R Rosas-Rodriguez

From the Holst action in terms of complex valued Ashtekar variables additional reality conditions mimicking the linear simplicity constraints of spin foam gravity are found. In quantum theory with the results of You and Rovelli we are able…

General Relativity and Quantum Cosmology · Physics 2012-01-25 Wolfgang Wieland

Cosmological perturbation equations are derived systematically in a canonical scheme based on Ashtekar variables. A comparison with the covariant derivation and various subtleties in the calculation and choice of gauges are pointed out.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Martin Bojowald , Hector H. Hernández , Mikhail Kagan , Parampreet Singh , Aureliano Skirzewski

We propose an explicit spin-foam amplitude for Lorentzian gravity in three dimensions, allowing for both space- and time-like boundaries. The model is based on two main requirements: that it should be structurally similar to its well-known…

General Relativity and Quantum Cosmology · Physics 2024-09-04 José Diogo Simão