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Related papers: Topological Interpretation of Barbero-Immirzi Para…

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We present the Hamiltonian analysis of the theory of gravity based on a Lagrangian density containing Hilbert-Palatini term along with three topological densities, Nieh-Yan, Pontryagin and Euler. The addition of these topological terms…

General Relativity and Quantum Cosmology · Physics 2012-01-24 Romesh K. Kaul , Sandipan Sengupta

A canonical formulation of the N=1 supergravity theory containing the topological Nieh-Yan term in its Lagrangian density is developed. The constraints are analysed without choosing any gauge. In the time gauge, the theory is shown to be…

High Energy Physics - Theory · Physics 2010-06-01 Sandipan Sengupta , Romesh K. Kaul

The most general gravity Lagrangian in four dimensions contains three topological densities, namely Nieh-Yan, Pontryagin and Euler, in addition to the Hilbert-Palatini term. We set up a Hamiltonian formulation based on this Lagrangian. The…

General Relativity and Quantum Cosmology · Physics 2012-06-01 Sandipan Sengupta

A possible topological interpretation of the Barbero-Immirzi parameter is proposed. Classically, by generalizing the Holst action to torsional spacetimes, we construct a precise analogy between the Barbero--Immirzi parameter and the…

General Relativity and Quantum Cosmology · Physics 2009-04-12 Simone Mercuri

In a classical theory of gravity, the Barbero-Immirzi parameter ($\eta$) appears as a topological coupling constant through the Lagrangian density containing the Hilbert-Palatini term and the Nieh-Yan invariant. In a quantum framework, the…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Sandipan Sengupta

In four dimensional gravity theory, the Barbero-Immirzi parameter has a topological origin, and can be identified as the coefficient multiplying the Nieh-Yan topological density in the gravity Lagrangian, as proposed by Date et al.[1].…

General Relativity and Quantum Cosmology · Physics 2013-07-29 Sandipan Sengupta

Starting from a Lagrangian we perform the full constraint analysis of the Hamiltonian for General relativity in the tetrad-connection formulation for an arbitrary value of the Immirzi parameter and solve the second class constraints,…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Nuno Barros e Sa

We consider gravity in 2+1 space-time dimensions, with negative cosmological constant and a `Barbero-Immirzi' (B-I) like parameter, when the space-time topology is of the form $ T^2 \times \mathbbm{R}$. The phase space structure, both in…

General Relativity and Quantum Cosmology · Physics 2010-05-07 Rudranil Basu , Samir K Paul

We shall here discuss a new spacetime gauge-covariant Lagrangian formulation of General Relativity by means of the Barbero-Immirzi SU(2)-connection on spacetime. To the best of our knowledge the Lagrangian based on SU(2) spacetime fields…

General Relativity and Quantum Cosmology · Physics 2008-11-26 L. Fatibene , M. Francaviglia , C. Rovelli

The Barbero-Immirzi parameter is a one parameter quantization ambiguity underpinning the loop approach to quantum gravity that bears tantalizing similarities to the theta parameter of gauge theories such as Yang-Mills and QCD. Despite the…

High Energy Physics - Theory · Physics 2011-01-17 Simone Mercuri , Andrew Randono

Fermions constitute an important component of matter and their quantization in presence of dynamical gravity is essential for any theory of quantum gravity. We revisit the classical formulation adapted for a background free quantization.…

General Relativity and Quantum Cosmology · Physics 2011-10-18 Ghanashyam Date

We study the role of the Barbero-Immirzi parameter $\gamma$ and the choice of connection in the construction of (a symmetry-reduced version of) loop quantum gravity. We start with the four-dimensional Lorentzian Holst action that we reduce…

General Relativity and Quantum Cosmology · Physics 2015-05-19 Jibril Ben Achour , Marc Geiller , Karim Noui , Chao Yu

We study the Hamiltonian formulation of the generally covariant theory defined by the Lagrangian 4-form L=e_I e_J F^{IJ}(\omega) where e^I is a tetrad field and F^{IJ} is the curvature of a Lorentz connection \omega^{IJ}. This theory can be…

General Relativity and Quantum Cosmology · Physics 2015-03-13 Lihui Liu , Merced Montesinos , Alejandro Perez

In this note, we review the canonical analysis of the Holst action in the time gauge, with a special emphasis on the Hamiltonian equations of motion and the fixation of the Lagrange multipliers. This enables us to identify at the…

General Relativity and Quantum Cosmology · Physics 2014-03-13 Marc Geiller , Karim Noui

We study the coupling of the gravitational action, which is a linear combination of the Hilbert-Palatini term and the quadratic torsion term, to the action of Dirac fermions. The system possesses local Poincare invariance and hence belongs…

General Relativity and Quantum Cosmology · Physics 2013-10-02 Jian Yang , Kinjal Banerjee , Yongge Ma

We present a parameter-free gauge formulation of general relativity in terms of a new set of real spin connection variables. The theory is constructed by extending the phase space of the recently formulated conformal geometrodynamics for…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Charles H. -T. Wang

Spacetime geometry is described by two -- {\em a priori} independent -- geometric structures: the symmetric connection $\Gamma$ and the metric tensor $g$. Metricity condition of $\Gamma$ (i.e. $\nabla g = 0$) is implied by the Palatini…

General Relativity and Quantum Cosmology · Physics 2024-03-15 B. Bąk , J. Kijowski

This letter is a critique of Barbero's constrained Hamiltonian formulation of General Relativity on which current work in Loop Quantum Gravity is based. While we do not dispute the correctness of Barbero's formulation of general relativity,…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Joseph Samuel

The Barbero-Immirzi (BI) parameter is promoted to a field and a canonical analysis is performed when it is coupled with a Nieh-Yan topological invariant. It is shown that, in the effective theory, the BI field is a canonical pseudoscalar…

General Relativity and Quantum Cosmology · Physics 2009-07-24 Gianluca Calcagni , Simone Mercuri

We present the Hamiltonian formulation of General Relativity with the Holst formulation in a generic local Lorentz frame. In particular, we outline that a Gauss constraint is inferred by a proper generalization of Ashtekar-Barbero-Immirzi…

General Relativity and Quantum Cosmology · Physics 2009-04-06 Francesco Cianfrani , Giovanni Montani
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