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Related papers: Loop quantum $f(R)$ theories

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We describe a deformation of the observable algebra of quantum gravity in which the loop algebra is extended to framed loops. This allows an alternative nonperturbative quantization which is suitable for describing a phase of quantum…

General Relativity and Quantum Cosmology · Physics 2009-09-25 Seth Major , Lee Smolin

The problem of finding the quantum theory of the gravitational field, and thus understanding what is quantum spacetime, is still open. One of the most active of the current approaches is loop quantum gravity. Loop quantum gravity is a…

General Relativity and Quantum Cosmology · Physics 2016-10-19 Carlo Rovelli

In this thesis we consider the problem of dynamics in canonical loop quantum gravity, primarily in the context of deparametrized models, in which a scalar field is taken as a physical time variable for the dynamics of the gravitational…

General Relativity and Quantum Cosmology · Physics 2021-01-01 Ilkka Mäkinen

Loop Quantum Gravity heavily relies on a connection formulation of General Relativity such that 1. the connection Poisson commutes with itself and 2. the corresponding gauge group is compact. This can be achieved starting from the Palatini…

General Relativity and Quantum Cosmology · Physics 2013-02-13 Norbert Bodendorfer , Thomas Thiemann , Andreas Thurn

On the basis of dynamic quantization method we build in this paper a new mathematically correct quantization scheme of gravity. In the frame of this scheme we develop a canonical formalism in tetrad-connection variables in 4-D theory of…

General Relativity and Quantum Cosmology · Physics 2016-08-31 S. N. Vergeles

Aspects of the full theory of loop quantum gravity can be studied in a simpler context by reducing to symmetric models like cosmological ones. This leads to several applications where loop effects play a significant role when one is…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Martin Bojowald

After a brief chronological sketch of developments in non-perturbative canonical quantum gravity, some of the recent mathematical results are reviewed. These include: i) an explicit construction of the quantum counterpart of Wheeler's…

General Relativity and Quantum Cosmology · Physics 2008-02-03 Abhay Ashtekar

General Relativity is an extremely successful theory, at least for weak gravitational fields, however, it breaks down at very high energies, such as in correspondence of the initial singularity. Quantum Gravity is expected to provide more…

General Relativity and Quantum Cosmology · Physics 2023-04-20 Ana Rita Ribeiro , Daniele Vernieri , Francisco S. N. Lobo

In a natural extension of the relativity principle we argue that a quantum theory of gravity involves two fundamental scales associated with both dynamical space-time as well as dynamical momentum space. This view of quantum gravity is…

High Energy Physics - Theory · Physics 2015-06-19 Laurent Freidel , Robert G. Leigh , Djordje Minic

We examine the singularity resolution issue in quantum gravity by studying a new quantization of standard Friedmann-Robertson-Walker geometrodynamics. The quantization procedure is inspired by the loop quantum gravity programme, and is…

General Relativity and Quantum Cosmology · Physics 2009-11-10 V. Husain , O. Winkler

We present a systematic approach to the kinematics of quantum-reduced loop gravity, a model originally proposed by Alesci and Cianfrani as an attempt to probe the physical implications of loop quantum gravity. We implement the quantum…

General Relativity and Quantum Cosmology · Physics 2024-12-03 Ilkka Mäkinen

A generalized quantization principle is considered, which incorporates nontrivial commutation relations of the components of the variables of the quantized theory with the components of the corresponding canonical conjugated momenta…

General Physics · Physics 2016-09-02 Martin Kober

Recently a class of alternative theories of gravity which goes under the name f(R) gravity, has received considerable attention, mainly due to its interesting applications in cosmology. However, the phenomenology of such theories is not…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Thomas P. Sotiriou , Stefano Liberati

In recent years, Loop Quantum Gravity has emerged as a solid candidate for a nonperturbative quantum theory of General Relativity. It is a background independent theory based on a description of the gravitational field in terms of…

General Relativity and Quantum Cosmology · Physics 2009-10-16 Guillermo A. Mena Marugan

Using the complex-valued self-dual connection variables, the loop quantum cosmology of a closed Friedmann universe coupled to a massless scalar field is studied. It is shown how the reality conditions can be imposed in the quantum theory by…

General Relativity and Quantum Cosmology · Physics 2016-04-07 Edward Wilson-Ewing

The recently proposed loop representation, used previously to find exact solutions to the quantum constraints of general relativity, is here used to quantize linearized general relativity. The Fock space of graviton states and its…

High Energy Physics - Theory · Physics 2010-11-01 Abhay Ashtekar , Carlo Rovelli , Lee Smolin

We review quantum gravity model building using the new formalism of `quantum Riemannian geometry' to construct this on finite discrete spaces and on fuzzy ones such as matrix algebras. The formalism starts with a `differential structure' as…

General Relativity and Quantum Cosmology · Physics 2022-06-07 J. N. Argota-Quiroz , S. Majid

Within the framework of Quantum Reduced Loop Gravity we quantize the Hamiltonian for a gauge vector field. The regularization can be performed using tools analogous to the ones adopted in full Loop Quantum Gravity, while the matrix elements…

General Relativity and Quantum Cosmology · Physics 2017-06-07 Jakub Bilski , Emanuele Alesci , Francesco Cianfrani , Pietro Donà , Antonino Marciano

We present a straightforward and self-contained introduction to the basics of the loop approach to quantum gravity, and a derivation of what is arguably its key result, namely the spectral analysis of the area operator. We also discuss the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Carlo Rovelli , Peush Upadhya

We relate three-dimensional loop quantum gravity to the combinatorial quantisation formalism based on the Chern-Simons formulation for three-dimensional Lorentzian and Euclidean gravity with vanishing cosmological constant. We compare the…

General Relativity and Quantum Cosmology · Physics 2012-02-07 C. Meusburger , K. Noui