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Related papers: Seeking the Loop Quantum Gravity Barbero-Immirzi P…

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Loop quantum gravity can account for the Bekenstein-Hawking entropy of a black hole provided a free parameter is chosen appropriately. Recently, it was proposed that a new choice of the Immirzi parameter could predict both black hole…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Alejandro Corichi

We review the canonical analysis of the Palatini action without going to the time gauge as in the standard derivation of Loop Quantum Gravity. This allows to keep track of the Lorentz gauge symmetry and leads to a theory of Covariant Loop…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Etera R. Livine

We consider cosmological solution for Einstein gravity with massive fermions with a four-fermion coupling, which emerges from the Holst action and is related to the Barbero-Immirzi (BI) parameter. This gravitational action is an important…

General Relativity and Quantum Cosmology · Physics 2015-06-03 G. de Berredo-Peixoto , L. Freidel , I. L. Shapiro , C. A. de Souza

In the context of the geometrical interpretation of the spin network states of Loop Quantum Gravity, we look at the holonomies of the Ashtekar-Barbero connection on loops embedded in space-like hyperboloids. We use this simple setting to…

General Relativity and Quantum Cosmology · Physics 2015-12-23 Christoph Charles , Etera R. Livine

In this paper we consider the quantization of the 2d BF model coupled to topological matter. Guided by the rigid supersymmetry this system can be viewed as a super-BF model, where the field content is expressed in terms of superfields. A…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Clisthenis P. Constantinidis , Ruan Couto , Ivan Morales , Olivier Piguet

We reexmine some proposals of black hole entropy in loop quantum gravity (LQG) and consider a new possible choice of the Immirzi parameter which has not been pointed out so far. We also discuss that a new idea is inevitable if we regard the…

High Energy Physics - Theory · Physics 2009-11-11 Takashi Tamaki , Hidefumi Nomura

We consider Regge calculus in the representation in terms of area tensors and self- and antiselfdual connections generalised to the case of Holst action that is standard Einstein action in the tetrad-connection variables plus topological…

High Energy Physics - Theory · Physics 2008-04-21 V. M. Khatsymovsky

A general construction of the Holst action is discussed. Based on this, the N = 1, 2, 4, 8 supergravities and N = 1 supergravities with matter coupling are presented. It is shown that in all this cases the Immirzi parameter dose not…

General Relativity and Quantum Cosmology · Physics 2012-03-09 Michal Szczachor

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

Higher-derivative operators are central elements of any effective field theory. In supersymmetric theories, these operators include terms with derivatives in the K\"ahler potential. We develop a toolkit for coupling such supersymmetric…

High Energy Physics - Theory · Physics 2015-05-30 Daniel Baumann , Daniel Green

We construct and study Loop Quantum Cosmology (LQC) when the Barbero-Immirzi parameter takes the complex value $\gamma=\pm i$. We refer to this new quantum cosmology as complex Loop Quantum Cosmology. We proceed in making an analytic…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Jibril Ben Achour , Julien Grain , Karim Noui

A modification of the harmonic superfield formalism in $D=4, N=2$ supergravity using a subsidiary condition of covariance under the background supersymmetry with a central charge ($B$-covariance) is considered. Conservation of analyticity…

High Energy Physics - Theory · Physics 2014-11-18 B. M. Zupnik

We reconsider the Rovelli-Smolin model of gravity coupled to the Klein-Gordon time field with an eye towards capturing the degrees of freedom of the scalar field lost in the framework in which time is deparametrized by the scalar field.…

General Relativity and Quantum Cosmology · Physics 2016-02-03 Jerzy Lewandowski , Hanno Sahlmann

We elaborate a full superfield description of the interacting system of dynamical D=4, N=1 supergravity and dynamical superstring. As far as minimal formulation of the simple supergravity is used, such a system should contain as well the…

High Energy Physics - Theory · Physics 2009-11-10 Igor A. Bandos , Jose M. Isidro

A new framework of loop quantization that assimilates conformal and scale invariance is constructed and is found to be applicable to a large class of physically important theories of gravity and gravity-matter systems. They include general…

General Relativity and Quantum Cosmology · Physics 2019-01-02 Charles H. -T. Wang , Daniel P. F. Rodrigues

We argue for black hole entropy in loop quantum gravity (LQG) by taking into account the interpretation that there is no other side of the horizon. This gives new values for the Barbero-Immirzi parameter which are fairly larger than those…

High Energy Physics - Theory · Physics 2008-11-26 Takashi Tamaki

A derivation of N=1 supergravity action from string theory is presented. Starting from a Nambu-Goto bosonic string, matter field is introduced to obtain a superstring in four dimension. The excitation quanta of this string contain graviton…

High Energy Physics - Theory · Physics 2009-11-11 B. B. Deo

We set up a canonical Hamiltonian formulation for a theory of gravity based on a Lagrangian density made up of the Hilbert-Palatini term and, instead of the Holst term, the Nieh-Yan topological density. The resulting set of constraints in…

General Relativity and Quantum Cosmology · Physics 2009-09-02 Ghanashyam Date , Romesh K. Kaul , Sandipan Sengupta

We recast the finite-region analysis of Einstein's equations that underpins the ER=EPR program into the loop quantum gravity (LQG) framework. By translating curvature-energy uncertainty relations into holonomy-flux kinematics, and by…

General Relativity and Quantum Cosmology · Physics 2025-08-29 Fabrizio Tamburini

We expect quantum field theories for matter to acquire intricate corrections due to their coupling to quantum fluctuations of the gravitational field. This can be precisely worked out in 3d quantum gravity: after integrating out quantum…

High Energy Physics - Theory · Physics 2024-06-06 Etera R. Livine , Valentine Maris