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Related papers: Loop quantum cosmology of Bianchi type IX models

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Loop quantum cosmology is an application of recent developments for a non-perturbative and background independent quantization of gravity to a cosmological setting. Characteristic properties of the quantization such as discreteness of…

Astrophysics · Physics 2009-11-13 Martin Bojowald

We present a gauge-invariant treatment of singularity resolution using loop quantum gravity techniques with respect to local SU(2) transformations. Our analysis reveals many novel features of quantum geometry which were till now hidden in…

General Relativity and Quantum Cosmology · Physics 2020-03-31 Klaus Liegener , Parampreet Singh

The dynamics and evolution of Bianchi type I space-times is considered in the framework of the four-dimensional truncation of a reduced theory obtained from the N=2,D=5 supergravity. The general solution of the gravitational field equations…

High Energy Physics - Theory · Physics 2009-10-31 Chiang-Mei Chen , T. Harko , M. K. Mak

Different regularizations of the Hamiltonian constraint in loop quantum cosmology yield modified loop quantum cosmologies, namely mLQC-I and mLQC-II, which lead to qualitatively different Planck scale physics. We perform a comprehensive…

General Relativity and Quantum Cosmology · Physics 2019-05-24 Sahil Saini , Parampreet Singh

The dynamics of the general Bianchi IX spacetime, near the gravitational singularity, underlies the Belinskii, Khalatnikov and Lifshitz scenario. Asymptotically, near the singularity, the oscillations of the directional scale factors…

General Relativity and Quantum Cosmology · Physics 2017-05-12 Andrzej Góźdź , Włodzimierz Piechocki , Grzegorz Plewa

We take the general quantum constraints of N=1 supergravity in the special case of a Bianchi metric, with gravitino fields constant in the invariant basis. We construct the most general possible wave function which solves the Lorentz…

General Relativity and Quantum Cosmology · Physics 2009-10-28 A. D. Y. Cheng , P. D. D'Eath

We study the dynamics of the Bianchi I universe in modified loop quantum cosmology (mLQC-I) and uncover a robust mechanism for isotropization: the shear is dynamically suppressed after the bounce and decays rapidly in the quantum…

General Relativity and Quantum Cosmology · Physics 2026-05-26 Wen-Cong Gan , Leila L. Graef , Rudnei O. Ramos , Gustavo S. Vicente , Anzhong Wang

We study the dynamics of the vacuum Bianchi IX model with timelike singularity and compare it with the dynamics of the Bianchi IX model with cosmological singularity. We show that differences in the signs of some terms in the set of…

General Relativity and Quantum Cosmology · Physics 2017-06-27 S. L. Parnovsky , W. Piechocki

Canonical quantum gravity provides insights into the quantum dynamics as well as quantum geometry of space-time by its implications for constraints. Loop quantum gravity in particular requires specific corrections due to its quantization…

General Relativity and Quantum Cosmology · Physics 2015-05-14 Martin Bojowald

We analyze the quantum dynamics of the Bianchi Type IX model, as described in the so-called polymer representation of quantum mechanics, to characterize the modifications that a discrete na- ture in the anisotropy variables of the Universe…

General Relativity and Quantum Cosmology · Physics 2013-12-24 Orchidea Maria Lecian , Giovanni Montani , Riccardo Moriconi

We use the vacuum Bianchi I model as an example to investigate the concept of physical evolution in Loop Quantum Cosmology (LQC) in the absence of the massless scalar field which has been used so far in the literature as an internal time.…

General Relativity and Quantum Cosmology · Physics 2009-11-05 Mercedes Martin-Benito , Guillermo A. Mena Marugan , Tomasz Pawlowski

We describe the quantum evolution of the vacuum Bianchi II universe in terms of the transition amplitude between two asymptotic quantum Kasner-like states. For large values of the momentum variable the classical and quantum calculations…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Hervé Bergeron , Orest Hrycyna , Przemysław Małkiewicz , Włodzimierz Piechocki

Loop quantum cosmology is a symmetry reduced quantization of cosmological spacetimes based on loop quantum gravity. While it has been successful in resolution of various cosmological singularities and connecting Planck scale physics to…

General Relativity and Quantum Cosmology · Physics 2019-12-25 Klaus Liegener , Parampreet Singh

In this paper we analyse the Bianchi IX Universe dynamics within the corner region associated to the potential term which the spatial curvature induces in the Minisuperspace. The study is done in the vacuum and in the presence of a massless…

General Relativity and Quantum Cosmology · Physics 2020-10-21 Roberta Chiovoloni , Giovanni Montani , Valerio Cascioli

In the last decade, progress on quantization of homogeneous cosmological spacetimes using techniques of loop quantum gravity has led to insights on various fundamental questions and has opened new avenues to explore Planck scale physics.…

General Relativity and Quantum Cosmology · Physics 2016-12-06 Ivan Agullo , Parampreet Singh

Some long standing issues concerning the quantum nature of the big bang are resolved in the context of homogeneous isotropic models with a scalar field. Specifically, the known results on the resolution of the big bang singularity in loop…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Abhay Ashtekar , Tomasz Pawlowski , Parampreet Singh

Canonical quantization of general relativity does not yield a unique quantum theory for gravity. This is in part due to operator ordering ambiguities. In this paper, we investigate the role of different operator orderings on the question of…

General Relativity and Quantum Cosmology · Physics 2019-08-21 Thibaut Demaerel , Ward Struyve

We develop a relativistic framework to investigate the evolution of cosmological structures from the initial density perturbations to the highly nonlinear regime. Our approach involves proposing a procedure to match ``best-fit", exact…

General Relativity and Quantum Cosmology · Physics 2024-04-29 Przemyslaw Malkiewicz , Jan J. Ostrowski , Ismael Delgado Gaspar

To inherit more features of full loop quantum Brans-Dicke theory, the Euclidean and Lorentzian terms of the Hamiltonian constraint are quantized independently in loop quantum Brans-Dicke cosmology. An alternative Hamiltonian constraint…

General Relativity and Quantum Cosmology · Physics 2020-07-15 Shupeng Song , Cong Zhang , Yongge Ma

We present a new cosmological model derived from Loop Quantum Gravity. The formulation is based on a projection of the kinematical Hilbert space of the full theory down to a subspace representing the proper arena for an inhomogeneous…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Emanuele Alesci , Francesco Cianfrani