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Related papers: Ambiguity of black hole entropy in loop quantum gr…

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We investigate a compelling model of a rotating black hole that is deformed by the effects of loop quantum gravity (LQG). We present a simplified metric and explore two distinct geometries: one in which the masses of the black hole and…

General Relativity and Quantum Cosmology · Physics 2024-12-24 Jafar Khodagholizadeh , Ghadir Jafari , Alireza Allahyari , Ali Vahedi

In this paper we discuss the entropy of quantum black holes in the LQG formalism when the number of punctures on the horizon is treated as a quantum hair, that is we compute the black hole entropy in the grand canonical (area) ensemble. The…

General Relativity and Quantum Cosmology · Physics 2012-08-30 Kinjalk Lochan , Cenalo Vaz

The black hole entropy calculation for type I isolated horizons, based on loop quantum gravity, is extended to include non-minimally coupled scalar fields. Although the non-minimal coupling significantly modifies quantum geometry, the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Abhay Ashtekar , Alejandro Corichi

The ambiguity in the calculations of one-loop counterterms by the background field method in nonrenormalizable theories of gravity is discussed. Some examples of such ambiguous calculations are given. The non-equivalence of the first and…

High Energy Physics - Theory · Physics 2007-05-23 M. Yu. Kalmykov , P. I. Pronin

Loop quantum gravity is a mature theory. To proceed to explicit calculations in cosmology, it is necessary to make assumptions and simplifications based on the symmetries of the cosmological setting. Symmetry reduction is especially…

General Relativity and Quantum Cosmology · Physics 2016-08-03 Aurélien Barrau , Boris Bolliet

We argue, using methods taken from the theory of noiseless subsystems in quantum information theory, that the quantum states associated with a Schwarzchild black hole live in the restricted subspace of the Hilbert space of horizon boundary…

High Energy Physics - Theory · Physics 2010-04-05 Olaf Dreyer , Fotini Markopoulou , Lee Smolin

Loop Quantum Gravity (LQG) is a promising approach to quantum gravity, in particular because it is based on a rigorous quantization of the kinematics of gravity. A difficult and still open problem in the LQG program is the construction of…

General Relativity and Quantum Cosmology · Physics 2013-03-01 Tim Koslowski

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

This is a (relatively) non -- technical summary of the status of the quantum dynamics in Loop Quantum Gravity (LQG). We explain in detail the historical evolution of the subject and why the results obtained so far are non -- trivial. The…

High Energy Physics - Theory · Physics 2008-11-26 Thomas Thiemann

This is a review of the results on black hole physics in the framework of loop quantum gravity. The key feature underlying the results is the discreteness of geometric quantities at the Planck scale predicted by this approach to quantum…

General Relativity and Quantum Cosmology · Physics 2017-11-22 Alejandro Perez

We portray the structure of quantum gravity emerging from recent progress in understanding the quantum mechanics of an evaporating black hole. Quantum gravity admits two different descriptions, based on Euclidean gravitational path integral…

High Energy Physics - Theory · Physics 2021-03-31 Yasunori Nomura

This is a brief overview of the current status of symmetry reduced models in Loop Quantum Gravity (LQG), focussing on the very early universe. Over the last 3 years or so the subject has matured sufficiently to make direct contact with…

General Relativity and Quantum Cosmology · Physics 2017-06-21 Abhay Ashtekar

We argue that the effective gauge group for {\it pure} four-dimensional loop quantum gravity(LQG) is SO(3) (or $SO(3,C)$) instead of SU(2) (or $SL(2,C)$). As a result, links with half-integer spins in spin network states are not realized…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Chung-Hsien Chou , Yi Ling , Chopin Soo , Hoi-Lai Yu

In this paper we present the spectrum of entropy/area for Kehagias-Sfetsos (KS) black hole in Ho$\check{\textbf{r}}$ava-Lifshitz (HL)gravity via quasi-normal modes (QNM) approach. We show that in the massive case the mass parameter $\mu$…

High Energy Physics - Theory · Physics 2011-02-22 M. R. Setare , D. Momeni

In loop quantum gravity, the number $N_\Gamma(A,\gamma)$ of microstates of a black hole for a given discrete geometry $\Gamma$ depends on the so-called Barbero-Immirzi parameter $\gamma$. Using a suitable analytic continuation of $\gamma$…

General Relativity and Quantum Cosmology · Physics 2014-07-08 Ernesto Frodden , Marc Geiller , Karim Noui , Alejandro Perez

In Loop Quantum Gravity (LQG) the quantisation of General Relativity leads to precise predictions for the eigenvalues of geometrical observables like volume and area, up to the value of the only free parameter of the theory, the…

General Relativity and Quantum Cosmology · Physics 2021-01-01 Cássio Pigozzo , Flora S. Bacelar , Saulo Carneiro

The lack of rotating black hole models, which are typically found in nature, in loop quantum gravity (LQG) substantially hinders the progress of testing LQG from observations. Starting with a non-rotating LQG black hole as a seed metric, we…

General Relativity and Quantum Cosmology · Physics 2021-05-07 Suddhasattwa Brahma , Che-Yu Chen , Dong-han Yeom

We draw parallels between the recently introduced ``Immirzi ambiguity'' of the Ashtekar-like formulation of canonical quantum gravity and other ambiguities that appear in Yang-Mills theories, like the $\theta$ ambiguity. We also discuss…

General Relativity and Quantum Cosmology · Physics 2009-10-31 R. Gambini , O. Obregon , J. Pullin

We investigate the interior structure, perturbations, and the associated quasinormal modes of a quantum black hole model recently proposed by Bodendorfer, Mele, and M\"unch (BMM). Within the framework of loop quantum gravity, the quantum…

General Relativity and Quantum Cosmology · Physics 2020-08-04 Mariam Bouhmadi-López , Suddhasattwa Brahma , Che-Yu Chen , Pisin Chen , Dong-han Yeom

To date, a mathematically consistent construction of effective rotating black hole models in the context of Loop Quantum Gravity (LQG) is still lacking. In this work, we start with the assumption that rotating LQG black hole metrics can be…

General Relativity and Quantum Cosmology · Physics 2022-10-05 Che-Yu Chen