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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

Conformal loop quantum gravity provides an approach to loop quantization through an underlying conformal structure i.e. conformally equivalent class of metrics. The property that general relativity itself has no conformal invariance is…

General Relativity and Quantum Cosmology · Physics 2017-10-06 Olivier J. Veraguth , Charles H. -T. Wang

A discussion is given of recent developments in canonical gravity that assimilates the conformal analysis of gravitational degrees of freedom. The work is motivated by the problem of time in quantum gravity and is carried out at the metric…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Charles H. -T. Wang

The emergence of loop quantum gravity over the past two decades has stimulated a great resurgence of interest in unifying general relativity and quantum mechanics. Amongst a number of appealing features of this approach are the intuitive…

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

A new canonical transformation is found that enables the direct canonical treatment of the conformal factor in general relativity. The resulting formulation significantly simplifies the previously presented conformal geometrodynamics. It…

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

The Immirzi parameter of loop quantum gravity is a one parameter ambiguity of the theory whose precise interpretation is not universally agreed upon. It is an inherent characteristic of the quantum theory as it appears in the spectra of…

General Relativity and Quantum Cosmology · Physics 2017-06-07 Patrick J. Wong

The 1-parameter family of transformations identified by Barbero and Immirzi plays a significant role in non-perturbative approaches to quantum gravity, among them Loop Quantum Gravity and Spin Foams. It facilitates the loop quantization…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Bianca Dittrich , James P. Ryan

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

The configuration space of the reduced Hamiltonian formulation of quantum gravity has been shown, for non-Ricci flat metrics, to be a higher-dimensional analogue of the Teichm\"{u}ller space of conformal structures on a Riemann surface. In…

General Relativity and Quantum Cosmology · Physics 2012-08-21 James A. Reid , Charles H. -T. Wang

An so(4,C)-covariant hamiltonian formulation of a family of generalized Hilbert-Palatini actions depending on a parameter (the so called Immirzi parameter) is developed. It encompasses the Ashtekar-Barbero gravity which serves as a basis of…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Sergei Alexandrov

We use a canonical parametrization of twisted geometries describing the classical phase space of loop quantum gravity on a fixed graph, and establish its explicit correspondence with the associated frame bases and spinorial descriptions.…

General Relativity and Quantum Cosmology · Physics 2026-04-09 Iñaki Garay , Sergio Rodríguez-González , Raül Vera

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

Barbero has generalized the Ashtekar canonical transformation to a one-parameter scale transformation $U(\iota)$ on the phase space of general relativity. Immirzi has noticed that in loop quantum gravity this transformation alters the…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Carlo Rovelli , Thomas Thiemann

A crucial property of Weyl gravity is its conformal invariance. It is shown how this gauge symmetry is exactly reflected by the two constraints in the Hamiltonian framework. Since the spatial 3-metric is one of the configuration variables,…

General Relativity and Quantum Cosmology · Physics 2018-09-26 Qian Chen , Yongge Ma

We present a new formulation for the canonical approach to conformal (Weyl-squared) gravity and its extension by the Einstein-Hilbert term and a nonminimally coupled scalar field. For this purpose we use a unimodular decomposition of the…

General Relativity and Quantum Cosmology · Physics 2017-04-19 Claus Kiefer , Branislav Nikolic

The Ashtekar-Barbero formulation of general relativity admits a one-parameter family of canonical transformations that preserves the expressions of the Gauss and diffeomorphism constraints. The loop quantization of the connection formalism…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Guillermo A. Mena Marugan

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

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

In this paper explore the relation between covariant and canonical approaches to quantum gravity and $BF$ theory. We will focus on the dynamical triangulation and spin-foam models, which have in common that they can be defined in terms of…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Matthias Arnsdorf

We present a new approach to the covariant canonical formulation of Einstein-Cartan gravity that preserves the full Lorentz group as the local gauge group. The method exploits lessons learned from gravity in 2+1 dimensions regarding the…

General Relativity and Quantum Cosmology · Physics 2008-12-18 Andrew Randono
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