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Related papers: Bianchi spacetimes in noncommutative phase-space

200 papers

We have studied particle motion in generalized forms of noncommutative phase space, that simulate monopole and other forms of Berry curvature, that can be identified as effective internal magnetic fields, in coordinate and momentum space.…

High Energy Physics - Theory · Physics 2008-11-26 B. Basu , Subir Ghosh , S. Dhar

We study the effects produced by nonlinear electrodynamics in spacetimes conformal to Bianchi metrics. In the presence of Born-Infeld type fields these models accelerate, expand and isotropize. This effect is compared with the corresponding…

High Energy Physics - Theory · Physics 2009-11-07 Ricardo Garcia-Salcedo , Nora Breton

A two-component formulation of the Klein-Gordon equation is used to investigate the cyclic and noncyclic adiabatic geometric phases due to spatially homogeneous (Bianchi) cosmological models. It is shown that no adiabatic geometric phases…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. Mostafazadeh

We construct algebra with noncommutativity of coordinates and noncommutativity of momenta which is rotationally invariant and equivalent to noncommutative algebra of canonical type. Influence of noncommutativity on the energy levels of…

Quantum Physics · Physics 2017-09-15 Kh. P. Gnatenko , V. M. Tkachuk

Space-times which allow a slicing into homogeneous spatial hypersurfaces generalize the usual Bianchi models. One knows already that in these models the Bianchi type may change with time. Here we show which of the changes really appear. To…

General Relativity and Quantum Cosmology · Physics 2009-10-28 M. Rainer , H. -J. Schmidt

In the last decades, noncommutative spacetimes and their deformed relativistic symmetries have usually been studied in the context of field theory, replacing the ordinary Minkowski background with an algebra of noncommutative coordinates.…

High Energy Physics - Theory · Physics 2017-08-21 Alessandro Moia

The dynamics of a class of cosmological models with collisionless matter and four Killing vectors is studied in detail and compared with that of corresponding perfect fluid models. In many cases it is possible to identify asymptotic states…

General Relativity and Quantum Cosmology · Physics 2009-10-31 A. D. Rendall , K. P. Tod

The set of coherent states for a noncommutative quantum Bianchi I anisotropic cosmology were built to circumvent the absence of a simultaneous set of configuration observables. By extending known methods of path integrals with coherent…

General Relativity and Quantum Cosmology · Physics 2014-03-13 Román Juárez , David Martínez

We study the anisotropic Bianchi I loop quantum cosmology in 2+1 dimensions. Both the $\mubar$ and $\mubar'$ schemes are considered in the present paper and the following expected results are established: (i) the massless scalar field again…

General Relativity and Quantum Cosmology · Physics 2020-10-23 You Ding , Xiangdong Zhang

In this thesis we study different aspects of noncommutativity in quantum mechanics, field theory and gravity. We give particular emphasis on the underlying symmetries of these theories. Deformations of usual symmetries like the external…

High Energy Physics - Theory · Physics 2010-06-08 Saurav Samanta

The comprehensive formulation for loop quantum cosmology in the spatially flat, isotropic model was recently constructed. In this paper, the methods are extended to the anisotropic Bianchi I cosmology. Both the precursor and the improved…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Dah-Wei Chiou

We study properties of a scalar quantum field theory on two-dimensional noncommutative space-times. Contrary to the common belief that noncommutativity of space-time would be a key to remove the ultraviolet divergences, we show that field…

High Energy Physics - Theory · Physics 2007-05-23 M. Chaichian , A. Demichev , P. Presnajder

For stationary vacuum spacetimes the Bianchi identities of the second kind equate the Simon tensor to the Simon-Mars tensor, the latter having a clear geometrical interpretation. The equivalence of these two tensors is broken in the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Donato Bini , Robert T. Jantzen

Einstein's field equations with variable gravitational and cosmological ``constant'' are considered in presence of perfect fluid for Bianchi type-I spacetime. Consequences of the four cases of the phenomenological decay of $\Lambda$ have…

General Relativity and Quantum Cosmology · Physics 2008-11-26 J. P. Singh , A. Pradhan , A. K. Singh

The global counterpart of infinitesimal symmetries of noncommutative space-time is discussed.

High Energy Physics - Theory · Physics 2009-11-11 C. Gonera , P. Kosinski , P. Maslanka , S. Giller

Fluctuation terms and higher moments of a quantum state imply corrections to the classical equations of motion that may have implications in early-universe cosmology, for instance in the state-dependent form of effective potentials. In…

General Relativity and Quantum Cosmology · Physics 2023-07-10 Martin Bojowald , Freddy Hancock

In this work, we are investigating the problem of integrability of Bianchi class A cosmological models. This class of systems is reduced to the form of Hamiltonian systems with exponential potential forms. The dynamics of Bianchi class A…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Andrzej J. Maciejewski , Marek Szydlowski

In this work, the effects of non-commutative and commutative vacua on the phase space generated by a scalar field in a scalar torsion scenario are investigated. For both classical and quantum regimes, the commutative and non-commutative…

General Relativity and Quantum Cosmology · Physics 2016-02-02 Haidar Sheikhahmadi , Ali Aghamohammadi , Khaled Saaidi

All diagonal proper Bianchi I space-times are determined which admit certain important symmetries. It is shown that for Homotheties, Conformal motions and Kinematic Self-Similarities the resulting space-times are defined explicitly in terms…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Michael Tsamparlis , Pantelis S. Apostolopoulos

The mathematical structure of higher-dimensional physical phase spaces of the nondiagonal Bianchi IX model is analyzed in the neighborhood of the cosmological singularity by using dynamical system methods. Critical points of the Hamiltonian…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Ewa Czuchry , Wlodzimierz Piechocki