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Related papers: Bianchi IX model: Reducing phase space

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The system of two-dimensional damped harmonic oscillator is revisited in the extended phase space. It is an old problem already addressed by many authors that we present here in some fresh points of view and carry on smoothly a whole…

Mathematical Physics · Physics 2018-11-09 Laure Gouba

In the present work we develop a strictly Hamiltonian approach to Thermodynamics. A thermodynamic description based on symplectic geometry is introduced, where all thermodynamic processes can be described within the framework of Analytic…

High Energy Physics - Theory · Physics 2016-08-02 M. C. Baldiotti , R. Fresneda , C. Molina

Bianchi VIII vacuum solutions to Einstein's equations are causally geodesically complete to the future, given an appropriate time orientation, and the objective of this article is to analyze the asymptotic behaviour of solutions in this…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Hans Ringstrom

In this paper, we investigate a non-canonical scalar field model in the background dynamics of anisotropic Locally Rotationally Symmetric (LRS) Bianchi type I universe where gravity is coupled minimally to scalar field which is taken as…

General Relativity and Quantum Cosmology · Physics 2023-11-17 Sujoy Bhanja , Goutam Mandal , Abdulla Al Mamon , Sujay Kr. Biswas

In the present work we revisit the axisymmetric Bianchi VIII and IX models. At the classical level we reproduce the known analytic solution, in a novel way making use of two quadratic integrals of motion, the constraint equation, as well as…

General Relativity and Quantum Cosmology · Physics 2019-04-10 A. Karagiorgos , T. Pailas , N. Dimakis , G. O. Papadopoulos , Petros A. Terzis , T. Christodoulakis

In this work, the quantization of the most general Bianchi Type I geometry, with and without a cosmological constant, is considered. In the spirit of identifying and subsequently removing as many gauge degrees of freedom as possible, a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 T. Christodoulakis , T. Gakis , G. O. Papadopoulos

The non-diagonal Bianchi models are studied in the loop framework for their classical and quantum formulation. The expressions of the Ashtekar-Barbero-Immirzi variables and their properties are found to provide a loop quantization of these…

General Relativity and Quantum Cosmology · Physics 2023-06-19 Matteo Bruno , Giovanni Montani

An operator-valued quantum phase space formula is constructed. The phase space formula of Quantum Mechanics provides a natural link between first and second quantization, thus contributing to the understanding of quantization problem. By…

Mathematical Physics · Physics 2017-03-16 Dong-Sheng Wang

Time-dependent potentials are common in galactic systems that undergo significant evolution, interactions, or encounters with other galaxies, or when there are dynamic processes like star formation and merging events. Recent studies show…

Astrophysics of Galaxies · Physics 2025-02-04 Eduárd Illés , Dániel Jánosi , Tamás Kovács

In this paper we study the evolution of spatially homogeneous and anisotropic Bianchi type-I Universe models with the cosmological constant, \Lambda, and filled with nonlinear viscous fluid. The dynamical equations for these models are…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Nouraddin Mostafapoor , Oyvind Gron

We use a dynamical systems approach based on the method of orthonormal frames to study the dynamics of a non-tilted Bianchi Type IX cosmological model with a bulk and shear viscous fluid source. We begin by completing a detailed fix-point…

General Relativity and Quantum Cosmology · Physics 2014-04-03 Ikjyot Singh Kohli , Michael C. Haslam

We use the expansion-normalized variables approach to study the dynamics of a non-tilted Bianchi Type I cosmological model with both a homogeneous magnetic field and a viscous fluid. In our model the perfect magnetohydrodynamic…

General Relativity and Quantum Cosmology · Physics 2014-02-26 Ikjyot Singh Kohli , Michael C. Haslam

We begin with a review of the statements of non-linear, linear and mode stability of autonomous dynamical systems in classical mechanics, using symplectic geometry. We then discuss what the phase space and the Hamiltonian of general…

General Relativity and Quantum Cosmology · Physics 2020-08-10 Prashant Kocherlakota , Pankaj S. Joshi

We consider a quantization of the Bianchi IX cosmological model based on taking the constraint to be a self-adjoint operator in an auxiliary Hilbert space. Using a WKB-style self-consistent approximation, the constraint chosen is shown to…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Donald Marolf

A detailed qualitative analysis and numerical modeling of the evolution of cosmological models based on nonlinear classical and phantom scalar fields with self-action are performed. Complete phase portraits of the corresponding dynamical…

General Relativity and Quantum Cosmology · Physics 2019-05-03 Yu. G. Ignat'ev , A. A. Agathonov

For an arbitrary possibly non-Hermitian matrix Hamiltonian H, that might involve exceptional points, we construct an appropriate parameter space M and the lines bundle L^n over M such that the adiabatic geometric phases associated with the…

Quantum Physics · Physics 2009-11-13 H. Mehri-Dehnavi , A. Mostafazadeh

We consider the Bianchi I geometry coupled to several species of comoving barotropic perfect fluids with a linear equation of state in the context of general relativity. The solution of the dynamics can be reduced to a quadrature, which can…

General Relativity and Quantum Cosmology · Physics 2024-10-29 David Brizuela , Sara F. Uria

We investigate the classical limit of non-Hermitian quantum dynamics arising from a coherent state approximation, and show that the resulting classical phase space dynamics can be described by generalised "canonical" equations of motion,…

Quantum Physics · Physics 2010-02-08 Eva-Maria Graefe , Michael Hoening , Hans Juergen Korsch

We study Hamiltonian flows in a real separable Hilbert space endowed with a symplectic structure. Measures on the Hilbert space that are invariant with respect to the flows of completely integrable Hamiltonian systems are investigated.…

Mathematical Physics · Physics 2024-10-10 Vladimir Glazatov , Vsevolod Sakbaev

The Bianchi IX cosmological model is analyzed in a generalized uncertainty principle framework. The Arnowitt-Deser-Misner reduction of the dynamics is performed and a time-coordinate, namely the volume of the Universe, naturally arises.…

General Relativity and Quantum Cosmology · Physics 2009-11-13 Marco Valerio Battisti , Giovanni Montani