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We study the effect of noncommutativity of space on the physics of a quantum interferometer located in a rotating disk in a gauge field background. To this end, we develop a path-integral approach which allows defining an effective action…

High Energy Physics - Theory · Physics 2010-11-19 H. R. Christiansen , F. A. Schaposnik

Deformed dispersion relations are considered in the study of equations of state of Fermi gas with applications to compact objects. Different choices of deformed energy relations are used in the formulation of our model. As a first test, we…

General Physics · Physics 2021-10-27 Luis C. N. Santos , Clésio E. Mota , Franciele M. da Silva , Guilherme Grams , I. P. Lobo

We consider the effects of noncommutativity and the generalized uncertainty principle on the FRW cosmology with a scalar field. We show that, the cosmological constant problem and removability of initial curvature singularity find natural…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. Bina , K. Atazadeh , S. Jalalzadeh

We consider the evolution of white dwarfs with compact object companions (specifically black holes with masses up to 10^6 solar masses, neutron stars, and other white dwarfs). We suppose that the orbits are initially quite elliptical and…

Astrophysics · Physics 2009-11-10 Yasser Rathore , Roger D. Blandford , Avery E. Broderick

We construct high-precision models of the Universe that contain radiation, a cosmological constant, and periodically distributed inhomogeneous matter. The density contrasts in these models are allowed to be highly non-linear, and the…

General Relativity and Quantum Cosmology · Physics 2017-02-24 Viraj A. A. Sanghai , Timothy Clifton

We discuss the propagation of dark matter perturbations with non-zero velocity dispersion in cosmological models. In particular a non-zero massive neutrino component may well have a significant effect on the matter power spectrum and cosmic…

Astrophysics · Physics 2009-11-07 Antony Lewis , Anthony Challinor

We consider a problem of the consistent deformation of physical system introducing a new features, but preserving its fundamental properties. In particular, we study how to implement the noncommutativity of space-time without violation of…

High Energy Physics - Theory · Physics 2014-09-15 V. G. Kupriyanov

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

Based on Berenstein and Retakh's notion of noncommutative polygons we introduce and study noncommutative frieze patterns. We generalize several notions and fundamental properties from the classic (commutative) frieze patterns to…

Combinatorics · Mathematics 2024-04-05 Michael Cuntz , Thorsten Holm , Peter Jorgensen

Using a fully-fledged formulation of gauge field theory deformed by the spacetime noncommutativity, we study its impact on relic neutrino direct detection, as proposed recently by the PTOLEMY experiment. The noncommutative background tends…

High Energy Physics - Phenomenology · Physics 2017-06-21 Raul Horvat , Josip Trampetic , Jiangyang You

A self-consistent theory for the classical description of the interaction of light and matter at the nano-scale is presented, which takes into account spatial dispersion. Up to now, the Maxwell equations in nanostructured materials with…

Optics · Physics 2020-10-07 J. V. Alvarez , Bahram Djafari-Rouhani , Dani Torrent

We propose a time-varying cosmological constant with a fixed equation of state, which evolves mainly through its interaction with the background during most of the long history of the universe. However, such interaction does not exist in…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-18 Murli Manohar Verma

We propose that the size of the universe and its rate of expansion cannot be simultaneously specified with arbitrary precision, a quantum mechanical statement encoded in a deformed commutation relation for the scale factor. The deformation…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-15 Savvas M. Koushiappas

Using the scalar and tensor virial equations, the Lane-Emden equation expressing the hydrostatic equilibrium and small oscillations around the equilibrium, we show how the cosmological constant $\Lambda$ affects various astrophysical…

Astrophysics · Physics 2009-11-13 A. Balaguera-Antolinez , M. Nowakowski

In this letter we study the effects of a noncommutative in the phase space of an empty (4+1) Kaluza-Klein universe with cosmological constant. We analyze the effects of the noncommutative deformations on the cosmological constant. Finally…

High Energy Physics - Theory · Physics 2013-07-09 E. Mena , S. Pérez-Payán , M. Sabido

The Newton equation describing the particle motion in constant external field force on canonical, Lie-algebraic and quadratic space-time is investigated. We show that for canonical deformation of space-time the dynamical effects are absent,…

Mathematical Physics · Physics 2009-01-27 Marcin Daszkiewicz , Cezary J. Walczyk

In the study of degenerate plasmas contained within compact astrophysical objects, both special relativity and general relativity play important roles. After reviewing the existing treatment in the literature, here we employ the methods of…

High Energy Astrophysical Phenomena · Physics 2022-01-20 Golam Mortuza Hossain , Susobhan Mandal

We study the impact of non-local modifications of General Relativity on stellar structure. In particular, assuming an analytic distortion function and specific equations of state, we made use of remnant stars to put qualitative constraints…

General Relativity and Quantum Cosmology · Physics 2023-01-23 Grigoris Panotopoulos , Javier Rubio , Ilídio Lopes

The quantum dynamics of nonrelativistic single particle systems involving noncommutative coordinates, usually referred to as noncommutative quantum mechanics, has lately been the object of several investigations. In this note we pursue…

Quantum Physics · Physics 2009-11-11 F. S. Bemfica , H. O. Girotti

Quantum corrections can be important for diffusion and the melting temperature of dense plasmas in compact astrophysical objects, particulary white dwarfs and neutron stars. Typically ions in these systems are modeled classically, but…

Solar and Stellar Astrophysics · Physics 2015-03-19 Justin Mason