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Related papers: Reality Conditions and Ashtekar Variables: a Diffe…

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We show how to treat the constraints and reality conditions in the $SO(3)$-ADM (Ashtekar) formulation of general relativity, for the case of a vacuum spacetime with a cosmological constant. We clarify the difference between the reality…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Gen Yoneda , Hisaaki Shinkai

We examine the advantages of the SO(3)-ADM (Ashtekar) formulation of general relativity, from the point of following the dynamics of the Lorentzian spacetime in direction of applying this into numerical relativity. We describe our strategy…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Hisa-aki Shinkai , Gen Yoneda

I suggest in this letter a new strategy to attack the problem of the reality conditions in the Ashtekar approach to classical and quantum general relativity. By writing a modified Hamiltonian constraint in the usual $SO(3)$ Yang-Mills phase…

General Relativity and Quantum Cosmology · Physics 2017-03-24 J. Fernando Barbero

We show that the reality conditions to be imposed on Ashtekar variables to recover real gravity can be implemented as second class constraints a la Dirac. Thus, counting gravitational degrees of freedom follows accordingly. Some constraints…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Hugo A. Morales-Tecotl , Luis F. Urrutia , J. David Vergara

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

We review the classical formulation of general relativity 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), and we add some new observations…

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

I show in this letter that it is possible to solve some of the constraints of the $SO(3)$-ADM formalism for general relativity by using an approach similar to the one introduced by Capovilla, Dell and Jacobson to solve the vector and scalar…

General Relativity and Quantum Cosmology · Physics 2017-03-24 J. Fernando Barbero

I show in this letter that it is possible to construct a Hamiltonian description for Lorentzian General Relativity in terms of two real $SO(3)$ connections. The constraints are simple polynomials in the basic variables. The present…

General Relativity and Quantum Cosmology · Physics 2017-03-24 J. Fernando Barbero

For various theories, in particular gauge field theories, the algebraic form of the Hamiltonian simplifies considerably if one writes it in terms of certain complex variables. Also general relativity when written in the new canonical…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Thomas Thiemann

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

We present a new $BF$-type action for complex general relativity with or without a cosmological constant resembling Plebanski's action, which depends on an SO(3,$\mathbb{C}$) connection, a set of 2-forms, a symmetric matrix, and a 4-form.…

General Relativity and Quantum Cosmology · Physics 2016-05-31 Mariano Celada , Diego González , Merced Montesinos

Using Ashtekar variables, we analyze Lorentzian and Euclidean gravity in vacuum up to a constant conformal transformation. We prove that the reality conditions are invariant under a Wick rotation of the time, and show that the compatibility…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Guillermo A. Mena Marugan

We perform the canonical analysis of the Holst action for general relativity with a cosmological constant without introducing second-class constraints. Our approach consists in identifying the dynamical and nondynamical parts of the…

General Relativity and Quantum Cosmology · Physics 2020-04-08 Merced Montesinos , Jorge Romero , Mariano Celada

We examine the constraints and the reality conditions that have to be imposed in the canonical theory of 4--d gravity formulated in terms of Ashtekar variables. We find that the polynomial reality conditions are consistent with the…

High Energy Physics - Theory · Physics 2010-04-06 Giorgio Immirzi

One can simplify the triad formulations of canonical gravity by abandoning any relation to a fixed coordinate system. That means in case of the \ADM formalism that one can determine the momentum by direct derivation of the Lagrange-3-form…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Joachim Schirmer

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

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

An action principle is described which unifies general relativity and topological field theory. An additional degree of freedom is introduced and depending on the value it takes the theory has solutions that reduce it to 1) general…

High Energy Physics - Theory · Physics 2007-05-23 Lee Smolin , Artem Starodubtsev

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

Related to the classical Ashtekar Hamiltonian, there have been discoveries regarding new classical actions for gravity in (2+1)- and (3+1)-dimensions, and also generalizations of Einstein's theory of gravity. In this review, I will try to…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Peter Peldan
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