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Related papers: Bianchi spacetimes in noncommutative phase-space

200 papers

We classify a class of Bianchi type II spacetimes according to their Noether symmetries. We briefly discuss the conservation laws admitted by these Noether symmetries and classify their possible algebras and determine their structures also.

Mathematical Physics · Physics 2015-02-10 Mahmood Rajih Tarayrah , Hassan Azad , Ashfaque H. Bokhari , F. D. Zaman

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

The representations of the algebra of coordinates and momenta of noncommutative phase space are given. We study, as an example, the harmonic oscillator in noncommutative space of any dimension. Finally the map of Sch$\ddot{o}$dinger…

High Energy Physics - Theory · Physics 2009-11-10 Kang Li , Jianhua Wang , Chiyi Chen

The one-loop effective potential for $\phi ^4$ theory on a Bianchi type-I universe is evaluated in the adiabatic approximation. It is used to see the quantum-field effects on symmetry breaking and restoration in anisotropic spacetimes. The…

General Relativity and Quantum Cosmology · Physics 2008-12-24 Wung-Hong Huang

We use our N\"other Symmetry Approach to study the Einstein equations minimally coupled with a scalar field, in the case of Bianchi universes of class A and B. Possible cases, when such symmetries exist, are found and two examples of exact…

General Relativity and Quantum Cosmology · Physics 2011-05-19 Salvatore Capozziello , Giuseppe Marmo , Claudio Rubano , Paolo Scudellaro

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

We introduce the perturbative aspects of noncommutative quantum mechanics. Then we study the Berry's phase in the framework of noncommutative quantum mechanics. The results show deviations from the usual quantum mechanics which depend on…

High Energy Physics - Theory · Physics 2009-11-07 S. A. Alavi

Within the scope of a Bianchi type-II (BII) cosmological model we study the role of a nonlinear spinor field in the evolution of the Universe. The system allows exact solutions only for some special choice of spinor field nonlinearity.

General Relativity and Quantum Cosmology · Physics 2015-05-28 Bijan Saha

We present exact quantum solutions for a noncommutative, multidimensional cosmological model and show that stabilization of extra dimensions sets in with the introduction of noncommutativity between the scale factors. An interpretation is…

General Relativity and Quantum Cosmology · Physics 2008-11-26 N. Khosravi , S. Jalalzadeh , H. R. Sepangi

We study coherent states for Bianchi type I cosmological models, as examples of semiclassical states for time-reparametrization invariant systems. This simple model allows us to study explicitly the relationship between exact semiclassical…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Brett Bolen , Luca Bombelli , Alejandro Corichi

In this work we examine the effect of phase-space noncommutativity on some typically quantum properties such as quantum beating, quantum information, and decoherence. To exemplify these issues we consider the two-dimensional noncommutative…

Quantum Physics · Physics 2015-10-13 Alex E. Bernardini , O. Bertolami

We consider a generalised non-commutative space-time in which non-commutativity is extended to all phase space variables. If strong enough, non-commutativity can affect stability of the system. We perform stability analysis on a couple of…

High Energy Physics - Theory · Physics 2018-08-31 Paolo Castorina , Alfredo Guerrera , Tomislav Prokopec

We formulate non-relativistic classical and quantum mechanics in the non-commutative two dimensional plane. The approach we use is based on the Galilei group, where the non-commutativity is seen as a central extension upon identification of…

Mathematical Physics · Physics 2007-05-23 C. A. Vaquera-Araujo , J. L. Lucio M

Understanding the early evolution of the universe requires models that incorporate possible quantum and anisotropic effects in its dynamics. In this work, we analyze the dynamical evolution of locally rotationally symmetric anisotropic…

General Relativity and Quantum Cosmology · Physics 2025-10-13 G. Oliveira-Neto , Y. Soncco Apaza

We present the classical solutions to the Einstein field equations derived using the WKB-like and Hamilton procedures. The investigation is carried out in the commutative and noncommutative scenario for the Bianchi type I cosmological model…

General Relativity and Quantum Cosmology · Physics 2009-11-13 C. Ortiz , E. Mena-Barboza , M. Sabido , J. Socorro

This paper investigates the possible cosmological implications of the presence of an antisymmetric tensor field related to a lack of commutatitivity of spacetime coordinates at the Planck era. For this purpose, such a field is promoted to a…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Elisabetta Di Grezia , Giampiero Esposito , Agostino Funel , Gianpiero Mangano , Gennaro Miele

Within the scope of Bianchi type-III spacetime we study the role of spinor field on the evolution of the Universe as well as the influence of gravity on the spinor field. In doing so we have considered a polynomial type of nonlinearity. In…

General Relativity and Quantum Cosmology · Physics 2016-03-16 Bijan Saha

The effects of noncommutativity on the phase space of a dilatonic cosmological model is investigated. The existence of such noncommutativity results in a deformed Poisson algebra between the minisuperspace variables and their momenta…

General Relativity and Quantum Cosmology · Physics 2010-04-30 B. Vakili , P. Pedram , S. Jalalzadeh

In this paper, we investigated the Pauli equation in a two-dimensional noncommutative phase-space by considering a constant magnetic field perpendicular to the plane. We mapped the noncommutative problem to the equivalent commutative one…

High Energy Physics - Theory · Physics 2021-10-11 Ilyas Haouam

A Bianchi type-I cosmological model in the presence of a magnetic flux along a cosmological string is considered. The first objective of this study is to investigate Einstein equations using a tractable assumption usually accepted in the…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Victor Rikhvitsky , Bijan Saha , Mihai Visinescu