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We show that it is possible to construct a quantum field theory that is invariant under the translation of the noncommutative parameter $\theta_{\mu\nu}$. This is realized in a noncommutative cohomological field theory. As an example, a…

High Energy Physics - Theory · Physics 2009-11-07 Tomomi Ishikawa , Shin-Ichiro Kuroki , Akifumi Sako

In this article an energy correction is calculated in the time independent perturbation setup using a regularised ultraviolet finite Hamiltonian on the noncommutative Minkowski space. The correction to the energy is invariant under rotation…

High Energy Physics - Theory · Physics 2008-11-26 Marcel Kossow

We present a first-quantized formulation of the quadratic non-commutative field theory in the background of abelian (gauge) field. Even in this simple case the Hamiltonian of a propagating particle depends non-trivially on the momentum…

High Energy Physics - Theory · Physics 2009-11-07 A. Dymarsky

We discuss non-commutative field theories in coordinate space. To do so we introduce pseudo-localized operators that represent interesting position dependent (gauge invariant) observables. The formalism may be applied to arbitrary field…

High Energy Physics - Theory · Physics 2007-05-23 David Berenstein , Robert G. Leigh

We study classical and quantum noncommutative cosmology with a Liouville-type scalar degree of freedom. The noncommutativity is imposed on the minisuperspace variables through a deformation of the Poisson algebra. In this paper, we…

General Relativity and Quantum Cosmology · Physics 2020-07-17 Nahomi Kan , Masashi Kuniyasu , Kiyoshi Shiraishi , Kohjiroh Takimoto

We compute the static potential in a non-commutative theory including a term due to UV/IR-mixing. As a result, the potential decays exponentially fast with distance rather than like a power law Coulomb type potential due to the exchange of…

High Energy Physics - Theory · Physics 2009-04-30 Robert C. Helling , Jiangyang You

Non locality appearing in QFT during the free evolution of localized field states and in the Feynman propagator function is analyzed. It is shown to be connected to the initial non local properties present at the level of quantum states and…

Quantum Physics · Physics 2009-04-28 Fabrizio Buscemi , Giuseppe Compagno

We discuss astrophysical implications of $\kappa$-Minkowski space-time, in which there appears space-time noncommutativity. We first derive a velocity formula for particles based on the motion of a wave packet. The result is that a massless…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Takashi Tamaki , Tomohiro Harada , Umpei Miyamoto , Takashi Torii

We consider simple extensions of noncommutativity from flat to curved spacetime. One possibility is to have a generalization of the Moyal product with a covariantly constant noncommutative tensor $\theta^{\mu\nu}$. In this case the…

High Energy Physics - Theory · Physics 2009-11-11 E. Harikumar , Victor O. Rivelles

In this paper, we further develop the analysis started in an earlier paper on the inequivalence of certain quantum field theories on noncommutative spacetimes constructed using twisted fields. The issue is of physical importance. Thus it is…

High Energy Physics - Theory · Physics 2010-04-22 A. P. Balachandran , A. Ibort , G. Marmo , M. Martone

This paper examines the causal structure of the commutator of two string fields, in free light-cone string field theory. By treating the commutator as a distribution on infinite dimensional loop space, it is shown that the commutator…

High Energy Physics - Theory · Physics 2009-10-22 D. A. Lowe

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

We clarify the relation between noncommutative spacetimes and multifractional geometries, two quantum-gravity-related approaches where the fundamental description of spacetime is not given by a classical smooth geometry. Despite their…

High Energy Physics - Theory · Physics 2017-02-06 Gianluca Calcagni , Michele Ronco

Interaction of linearized gravitational waves with a otherwise free particle has been studied quantum mechanically in a noncommutative phase-space to examine whether the particle's response to the gravitational wave gets modified due to…

General Relativity and Quantum Cosmology · Physics 2014-01-28 Sunandan Gangopadhyay , Anirban Saha , Swarup Saha

We examine noncommutative linear sigma models with U(N) global symmetry groups at the one-loop quantum level, and contrast the results with our previous study of the noncommutative O(N) linear sigma models where we have shown that…

High Energy Physics - Theory · Physics 2009-11-07 Bruce A. Campbell , Kirk Kaminsky

Landau system in noncommutative space has been considered. To take into account the issue of gauge invariance in noncommutative space, we incorporate the Seiberg-Witten map in our analysis. Generalised Bopp-shift transformation is then used…

High Energy Physics - Theory · Physics 2017-04-05 Aslam Halder , Sunandan Gangopadhyay

We study field theories on the noncommutative Minkowski space with noncommuting time. The focus lies on dispersion relations in quantized interacting models in the Yang-Feldman formalism. In particular, we compute the two-point correlation…

High Energy Physics - Theory · Physics 2007-07-17 Jochen Zahn

Irreducibility of the set of quantum field operators has been proved in noncommutative quantum field theory in the general case when time does not commute with spatial variables.

Mathematical Physics · Physics 2013-11-06 M. N. Mnatsakanova , Yu. S. Vernov

In this paper, we study the corrections to tree level scattering that arise due to noncommutative deformations of cubic scalar field theory through implementation of the Groenewald-Moyal(GM) product. The additional noncommutative refinement…

High Energy Physics - Theory · Physics 2018-06-29 Nikhil Kalyanapuram

We study the asymptotic stability of de Sitter spacetime with respect to non-linear perturbations, by considering second order perturbations of a flat Robertson-Walker universe with dust and a positive cosmological constant. Using the…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Marco Bruni , Filipe C. Mena , Reza Tavakol