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Related papers: Noncommutative Mixmaster Cosmologies

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I will summarize Noncommutative Geometry Spectral Action, an elegant geometrical model valid at unification scale, which offers a purely gravitational explanation of the Standard Model, the most successful phenomenological model of particle…

High Energy Physics - Theory · Physics 2011-05-24 Mairi Sakellariadou

We propose a cosmological model that describes isotropic expansion of inhomogeneous universe. The energy-momentum tensor that creates the spatial inhomogeneity may not affect the uniform expansion scaling factor $a(t)$ in the FLRW-like…

High Energy Physics - Theory · Physics 2014-10-15 Wei-Jian Geng , H. Lu

Within the scope of a Bianchi type-I (BI) cosmological model we study the interacting system of spinor and electromagnetic fields and its role in the evolution of the Universe. In some earlier studies it was found that in case of a pure…

General Relativity and Quantum Cosmology · Physics 2023-07-21 Bijan Saha

We study in detail the structure of phase space in the neighborhood of stable periodic orbits in a rotating 3D potential of galactic type. We have used the color and rotation method to investigate the properties of the invariant tori in the…

Chaotic Dynamics · Physics 2017-01-09 M. Katsanikas , P. A. Patsis

An integrable Hamiltonian system presents monodromy if the action-angle variables cannot be defined globally. As a prototype of classical monodromy with azimuthal symmetry, we consider a linear molecule interacting with external fields and…

Mathematical Physics · Physics 2022-04-06 Juan J. Omiste , Rosario González-Férez , Rafael Ortega

Composite system is studied in noncommutative phase space with preserved rotational symmetry. We find conditions on the parameters of noncommutativity on which commutation relations for coordinates and momenta of the center-of-mass of…

Quantum Physics · Physics 2018-02-27 Kh. P. Gnatenko , V. M. Tkachuk

Partial dynamical symmetry describes a situation in which some eigenstates have a symmetry which the quantum Hamiltonian does not share. This property is shown to have a classical analogue in which some tori in phase space are associated…

chao-dyn · Physics 2009-10-28 A. Leviatan , N. D. Whelan

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 investigate the possible effects on the evolution of perturbations in the inflationary epoch due to short distance physics. We introduce a suitable non local action for the inflaton field, suggested by Noncommutative Geometry, and…

High Energy Physics - Theory · Physics 2009-11-07 Fedele Lizzi , Gianpiero Mangano , Gennaro Miele , Marco Peloso

Active colloidal particles provide versatile model systems for exploring non-equilibrium physics in motile matter. To date, most experimental realizations have focused on spherical particles, largely due to fabrication constraints. However,…

Soft Condensed Matter · Physics 2026-04-10 Mengshi Wei , Daniela J. Kraft

In this work, we conduct a noncommutative analysis of a Bianchi I model coupled to a reduced relativistic gas. The classical field equations are modified by introducing noncommutativity through a generalized symplectic formalism. We observe…

General Relativity and Quantum Cosmology · Physics 2025-05-13 Thiago Moralles de Abreu , Gil de Oliveira Neto , Albert Carlo Rodrigues Mendes , Simpliciano Castardelli dos Reis

A short introduction on elements of noncommutative geometry, which offers a purely geometric interpretation of the Standard Model and implies a higher derivative gravitational theory, is presented. Physical consequences of almost…

High Energy Physics - Theory · Physics 2016-05-13 Mairi Sakellariadou

We investigate the effects of noncommutativity between the position-position, position-momentum and momentum-momentum of a phase space corresponding to a modified cosmological model. We show that the existence of such noncommutativity…

General Relativity and Quantum Cosmology · Physics 2015-06-23 B. Malekolkalami , K. Atazadeh , B. Vakili

We provide a Hamiltonian analysis of the Mixmaster Universe dynamics on the base of a standard Arnowitt-Deser-Misner Hamiltonian approach, showing the covariant nature of its chaotic behaviour with respect to the choice of any time…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Giovanni Imponente , Giovanni Montani

We derive the path integral action for a particle moving in three dimensional fuzzy space. From this we extract the classical equations of motion. These equations have rather surprising and unconventional features: They predict a cut-off in…

High Energy Physics - Theory · Physics 2018-12-05 FG Scholtz

Cosmological consequences of the noncommutative geometry spectral action are presented. Neglecting the nonminimal coupling of the Higgs field to the curvature, background cosmology remains unchanged, and only the inhomogeneous perturbations…

High Energy Physics - Theory · Physics 2015-05-14 Mairi Sakellariadou

We analyze the leading terms of the spectral action for a model of noncommutative geometry, which is a product of $4$-dimensional Riemannian manifold with a two-point space exploring the previously neglected case when the metrics over each…

Mathematical Physics · Physics 2019-12-17 Andrzej Sitarz

Current observational data is consistent with the universe being slightly closed. We investigate families of singular and non-singular closed instantons that could describe the beginning of a closed inflationary universe. We calculate the…

Astrophysics · Physics 2009-11-07 Steven Gratton , Antony Lewis , Neil Turok

The "central" region of moduli space of M- and string theories is where the string coupling is about unity and the volume of compact dimensions is about the string volume. Here we argue that in this region the non-perturbative potential…

High Energy Physics - Theory · Physics 2009-11-07 R. Brustein , S. P. de Alwis , E. G. Novak

We analyze a new class of time-periodic nonreciprocal dynamics in interacting chaotic classical spin systems, whose equations of motion are conservative (phase-space-volume-preserving) yet possess no symplectic structure. As a result, the…

Statistical Mechanics · Physics 2023-11-09 Adam J. McRoberts , Hongzheng Zhao , Roderich Moessner , Marin Bukov