English
Related papers

Related papers: Lyman-Alpha Spectroscopy in Non-Commutative Space-…

200 papers

We study cosmological consequences of the noncommutative approach to the standard model. Neglecting the nonminimal coupling of the Higgs field to the curvature, noncommutative corrections to Einstein's equations are present only for…

High Energy Physics - Theory · Physics 2010-05-12 William Nelson , Mairi Sakellariadou

The world-sheet quantum conformal invariance can be realized in the presence of the conformal factor $F$, by inclusion of Liouville term. In the background with linear dilaton field, $\Phi(x)=\Phi_0+a_\mu x^\mu$, the field $F$ becomes a new…

High Energy Physics - Theory · Physics 2010-05-11 B. Nikolic , B. Sazdovic

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

In this work we carry out a noncommutative analysis of several Friedmann-Robert-Walker models, coupled to different types of perfect fluids and in the presence of a cosmological constant. The classical field equations are modified, by the…

High Energy Physics - Theory · Physics 2015-06-03 E. M. C. Abreu , M. V. Marcial , A. C. R. Mendes , W. Oliveira , G. Oliveira-Neto

The efforts in this contribution consist in reassessing a modified Dirac equation that incorporates a $\gamma^0 \gamma_5$-Lorentz-symmetry violating (LSV) term induced as a Loop Quantum Gravity (LQG) effect. Originally, this equation has…

High Energy Physics - Theory · Physics 2024-09-19 João Paulo S. Melo , Mario J. Neves , Jefferson M. A. Paixão , José A. Helayël-Neto

Large surveys for Lyman-alpha emitting (LAE) galaxies have been proposed as a new method for measuring clustering of the galaxy population at high redshift with the goal of determining cosmological parameters. However, Lyman-alpha radiative…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Bradley Greig , Eiichiro Komatsu , J. Stuart B. Wyithe

The connection between Lorentz invariance violation and noncommutativity of fields in a quantum field theory is investigated. A new dispersion relation for a free field theory with just one additional noncommutative parameter is obtained.…

High Energy Physics - Theory · Physics 2009-11-07 J. M. Carmona , J. L. Cortes , J. Gamboa , F. Mendez

We show that the cosmological constant appears as a Lagrange multiplier if nature is described by a canonical noncommutative spacetime. It is thus an arbitrary parameter unrelated to the action and thus to vacuum fluctuations. The…

High Energy Physics - Theory · Physics 2008-11-26 Xavier Calmet

We consider a charged particle moving in a two dimensional plane in the presence of a background magnetic field perpendicular to the plane, i.e. the Landau system in a phase-space where the coordinates and momenta both follow canonical…

High Energy Physics - Theory · Physics 2017-01-04 Sunandan Gangopadhyay , Anirban Saha , Aslam Halder

Starting with the first-order singular Lagrangian containing the redundant variables, the noncommutative quantum mechanics on a curved space is investigated by the constraint star-product quantization formalism of the projection operator…

High Energy Physics - Theory · Physics 2016-10-06 M. Nakamura

The possibility of detecting noncommutative space relics is analyzed using the Aharonov-Bohm effect. We show that, if space is noncommutative, the holonomy receives non-trivial kinematical corrections that will produce a diffraction pattern…

High Energy Physics - Theory · Physics 2009-11-07 H. Falomir , J. Gamboa , M. Loewe , F. Mendez , J. C. Rojas

In this paper we endeavour to determine the energy levels of an atom by virtue of the modified Dirac equation. It has been found that the energy levels contain an extra term in the expression which accounts for the {\it zitterbewegung}…

General Physics · Physics 2017-05-05 A. Das , B. G. Sidharth

By the large and small wave-function components approach we achieved the nonrela-tivistic limit of the Dirac equation in interaction with an electromagnetic potential in noncommutative phase-space, and we tested the effect of the…

Quantum Physics · Physics 2018-09-18 Ilyas Haouam

We discuss the asymmetry of cosmic background evolution in time with respect to the quantum bounce in the Loop Quantum Cosmology (LQC), employing the value of scalar field at the bounce $\phi_{\rm B}$. We use the Chaotic and the $R^2$…

General Relativity and Quantum Cosmology · Physics 2019-07-03 Wen-Hsuan Lucky Chang , Jiun-Huei Proty Wu

We investigate the impact of modified-gravity models on the Lyman-$\alpha$ power spectrum. Building a simple analytical modeling, based on a truncated Zeldovich approximation, we estimate the intergalactic medium power spectrum and the…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-30 Philippe Brax , Patrick Valageas

We extend our earlier work of revealing both space-space and space-time noncommuting structures in various models in particle mechanics exhibiting reparametrisation symmetry. We show explicitly (in contrast to the earlier results in our…

High Energy Physics - Theory · Physics 2008-11-26 Sunandan Gangopadhyay

We study single field inflation in noncommutative spacetime and compute two-point and three-point correlation functions for the curvature perturbation. We find that both power spectrum and bispectrum for comoving curvature perturbation are…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-20 Akhilesh Nautiyal

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

The Lyman-alpha forest is a portion of the observed light spectrum of distant galactic nuclei which allows us to probe remote regions of the Universe that are otherwise inaccessible. The observed Lyman-alpha forest of a quasar light…

We study the physical properties of the persistent charged current in a metal ring on a noncommutative phase space, and temperature dependence of the noncommutative corrections are also analyzed. We find that the coordinate noncommutativity…

High Energy Physics - Theory · Physics 2018-06-13 Kai Ma , Ya-Jie Ren , Ya-Hui Wang