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Related papers: Ashtekar Variables in Classical General Realtivity

200 papers

This is a review with the ambitious goal of covering the recent progress in: 1) universal relations (in general relativity and alternative theories of gravity), and 2) neutron star models in alternative theories. We also aim to be…

General Relativity and Quantum Cosmology · Physics 2019-03-06 Daniela D. Doneva , George Pappas

Using a key observation due to Thiemann, a generalized Wick transform is introduced to map the constraint functionals of Riemannian general relativity to those of the Lorentzian theory, including matter sources. This opens up a new avenue…

General Relativity and Quantum Cosmology · Physics 2010-01-06 Abhay Ashtekar

General relativity has previously been extended to incorporate degenerate metrics using Ashtekar's hamiltonian formulation of the theory. In this letter, we show that a natural alternative choice for the form of the hamiltonian constraints…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Ted Jacobson , Joseph D. Romano

We show the equivalence of the Lorentz-covariant canonical formulation considered for the Immirzi parameter $\beta=i$ to the selfdual Ashtekar gravity. We also propose to deal with the reality conditions in terms of Dirac brackets derived…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Sergei Alexandrov

This is our reply to "Critical remarks on Finslerian modifications of gravity and cosmology by Zhe Chang and Xin Li", Sergiu I. Vacaru, Phys. Lett. B 690 (2010) 224. It is pointed out that the Finslerian modifications of gravity and…

General Relativity and Quantum Cosmology · Physics 2010-07-23 Xin Li , Zhe Chang

We derive a canonical analysis of a double null 2+2 Hamiltonian description of General Relativity in terms of complex self-dual 2-forms and the associated SO(3) connection variables. The algebra of first class constraints is obtained and…

General Relativity and Quantum Cosmology · Physics 2009-11-11 R. A. d'Inverno , P Lambert , J. A. Vickers

Using self dual Ashtekar variables, we investigate (at the effective level) the spherically symmetry reduced model of loop quantum gravity, both in vacuum and when coupled to a scalar field. Within the real Ashtekar-Barbero formulation, the…

General Relativity and Quantum Cosmology · Physics 2017-07-12 Jibril Ben Achour , Suddhasattwa Brahma , Antonino Marciano

Last years a certain attention was attracted to the statement that Hamiltonian formulations of General Relativity, in which different parametrizations of gravitational variables were used, may not be related by a canonical transformation.…

General Relativity and Quantum Cosmology · Physics 2011-03-28 T. P. Shestakova

We perform canonical quantization of General Relativity, as an effective quantum field theory below the Planck scale, within the BRST-invariant framework. We show that the promotion of constraints to dynamical equations of motion for…

High Energy Physics - Theory · Physics 2024-09-30 Lasha Berezhiani , Gia Dvali , Otari Sakhelashvili

The Hamilton-Jacobi analysis of three dimensional gravity defined in terms of Ashtekar-like variables is performed. We report a detailed analysis where the complete set of Hamilton-Jacobi constraints, the characteristic equations and the…

General Relativity and Quantum Cosmology · Physics 2020-02-28 Alberto Escalante , M. Eduardo Hernández-García

A model is proposed to demonstrate that classical general relativity can emerge from loop quantum gravity, in a relational description of gravitational field in terms of the coordinates given by matter. Local Dirac observables and coherent…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Chun-Yen Lin

I attempt to answer the question of the title by giving an annotated list of the major results achieved, over the last six years, in the program to construct quantum general relativity using the Ashtekar variables and the loop…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Lee Smolin

We propose a naive unification of Electromagnetism and General Relativity based on enlarging the gauge group of Ashtekar's new variables. We construct the connection and loop representations and analyze the space of states. In the loop…

High Energy Physics - Theory · Physics 2009-12-30 R. Gambini , J. Pullin

A new representation for canonical gravity and supergravity is presented, which combines advantages of Ashtekar's and the Wheeler~DeWitt representation: it has a nice geometric structure and the singular metric problem is absent. A formal…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Hans-Juergen Matschull

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

Ashtekar's variables are shown to arise naturally from a 3+1 split of general relativity in the Einstein-Cartan formulation. Thereby spinors are exorcised.

General Relativity and Quantum Cosmology · Physics 2009-06-29 Thomas Schucker

The original Schrodinger's paper is translated and annotated in honour of the 70-th anniversary of his Uncertainty Relation [published also in: Bulg. Journal of Physics,vol.26,no.5/6 (1999) pp.193-203]. In the annotation it is shown that…

Quantum Physics · Physics 2008-05-23 annotated by A. Angelow , M. -C. Batoni

We find a supersymmetrization of the Bianchi IX cosmology in terms of Ashtekar's new variables. This provides a framework for connecting the recent results of Graham and those of Ryan and Moncrief for quantum states of this model. These…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Octavio Obregon , Jorge Pullin , Michael P. Ryan

The favored classical variables that are promoted to quantum operators are divided into three sets that feature constant positive curvatures, constant zero curvatures, as well as constant negative curvatures. This list covers the spin…

General Physics · Physics 2020-11-25 John R. Klauder

This is an introduction to quantum gravity, aimed at a fairly general audience and concentrating on what have historically two main approaches to quantum gravity: the covariant and canonical programs (string theory is not covered). The…

General Relativity and Quantum Cosmology · Physics 2007-05-23 David Wallace