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Related papers: Noncommutative Mixmaster Cosmologies

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We revisit spatially flat, anisotropic cosmologies within the framework of mini-superspace. Putting special emphasis on the symmetries of the mini-superspace action and on the associated conservation laws, we unveil a new class of rotating…

High Energy Physics - Theory · Physics 2022-10-26 Alberto Nicolis , Federico Piazza , Kenza Zeghari

We investigate the appearance of the classical anisotropic universe from the no-boundary quantum state according to the prescription proposed by Hartle, Hawking and Hertog. Our model is homogeneous, anisotropic, closed universes with a…

General Relativity and Quantum Cosmology · Physics 2009-09-02 Kazuya Fujio , Toshifumi Futamase

We find transformation matrices allowing to express non-commutative three dimensional harmonic oscillator in terms of an isotropic commutative oscillator, following ``philosophy of simplicity'' approach. Non-commutative parameters have…

High Energy Physics - Theory · Physics 2009-11-07 A. Smailagic , E. Spallucci

In this work, we examine the dynamical aspects of the cosmological Mixmaster model within the framework of non-commutative generalized uncertainty principle (GUP) theories. The theory is formulated classically by introducing a well-defined…

General Relativity and Quantum Cosmology · Physics 2025-04-04 Sebastiano Segreto , Giovanni Montani

The appearance of noncommuting spatial coordinates is studied in quantum systems containing a magnetic monopole and under the influence of a radial potential. We derive expressions for the commutators of the coordinates that have been…

High Energy Physics - Theory · Physics 2010-01-26 Jan Govaerts , Sean Murray

Inflationary cosmologies, regarded as dynamical systems, have rather simple asymptotic behavior, insofar as the cosmic baldness principle holds. Nevertheless, in the early stages of an inflationary process, the dynamical behavior may be…

General Relativity and Quantum Cosmology · Physics 2009-10-22 E. Calzetta , C. El Hasi

Classical spectral theory gives a complete description of a single normal operator, but it fails for noncommuting operators, where no canonical joint spectrum or simultaneous diagonalization exists. Existing approaches provide only partial…

Category Theory · Mathematics 2026-01-27 Shih-Yu Chang

We analyze the semiclassical and quantum behavior of the Bianchi IX Universe in the Polymer Quantum Mechanics framework, applied to the isotropic Misner variable, linked to the space volume of the model. The study is performed both in the…

General Relativity and Quantum Cosmology · Physics 2018-11-06 Chiara Crinò , Giovanni Montani , Giorgio Pintaudi

We review the noncommutative spectral geometry, a gravitational model that combines noncommutative geometry with the spectral action principle, in an attempt to unify General Relativity and the Standard Model of electroweak and strong…

High Energy Physics - Theory · Physics 2014-03-25 Mairi Sakellariadou

Non-Hermitian systems have been discussed mostly in the context of open systems and nonequilibrium. Recent experimental progress is much from optical, cold-atomic, and classical platforms due to the vast tunability and clear identification…

Mesoscale and Nanoscale Physics · Physics 2024-01-25 Xiao-Xiao Zhang , Naoto Nagaosa

We present preliminary results on a new family of distribution functions that are able to generate axisymmetric, truncated (i.e., finite size) stellar dynamical models characterized by toroidal shapes. The relevant distribution functions…

Astrophysics · Physics 2009-11-10 L. Ciotti , G. Bertin , P. Londrillo

These lectures deal mainly with solitons in three-dimensional Moyal-deformed sigma models. The topics are: static and moving (multi-)solitons of the (integrable) Ward sigma model, with space-space and time-space noncommutativity, their…

High Energy Physics - Theory · Physics 2017-08-23 Olaf Lechtenfeld

We demonstrate that a class of modulation spaces are examples of a smooth structure on the noncommutative 2-torus in the sense of recent developments in KK-theory. In addition, we prove that this class of modulation spaces can be…

Operator Algebras · Mathematics 2019-06-06 Are Austad , Franz Luef

Quantum dynamics of a collection of atoms subjected to phase modulation has been carefully revisited. We present an exact analysis of the evolution of a two-level system (represented by a spinor) under the action of a time-dependent matrix…

Quantum Physics · Physics 2024-11-20 Rahul Gupta , Manan Jain , Sudhir R. Jain

We study polarized Gowdy cosmologies on the three torus coupled to a massive scalar field. The phase space of the model admits a simple splitting between homogeneous and inhomogeneous sectors after a suitable gauge fixing. The presence of…

General Relativity and Quantum Cosmology · Physics 2021-12-28 Javier Olmedo

The relation between symmetry breaking in non-commutative cut-off field theories and transitions to inhomogeneous phases in condensed matter is discussed. The non-commutative dynamics can be regarded as an effective description of the…

High Energy Physics - Theory · Physics 2009-11-10 Paolo Castorina , Giuseppe Riccobene , Dario Zappala'

We study the isospectral deformations of the Eguchi-Hanson spaces along a torus isometric action in the noncompact noncommutative geometry. We concentrate on locality, smoothness and summability conditions of the nonunital spectral triples,…

Operator Algebras · Mathematics 2009-11-13 C. Yang

Low energy effective actions arising from string theory typically contain many scalar fields, some with a very complicated potential and others with no potential at all. The evolution of these scalars is of great interest. Their late time…

High Energy Physics - Theory · Physics 2008-11-26 Brian Greene , Simon Judes , Janna Levin , Scott Watson , Amanda Weltman

The pseudo-spectral method is proposed for following the evolution of density and velocity fluctuations at the weakly non-linear stage in the expanding universe with a good accuracy. In this method, the evolution of density and velocity…

Astrophysics · Physics 2017-02-01 Naoteru Gouda

We discuss the asymptotic dynamical evolution of spatially homogeneous brane-world cosmological models close to the initial singularity. We find that generically the cosmological singularity is isotropic in Bianchi type IX brane-world…

High Energy Physics - Theory · Physics 2010-04-06 A. Coley