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Related papers: Discrete Symmetries in Dynamo Reversals

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We present an extension to simple s-d models, aiming at simulating ultrafast magnetization dynamics and spin transport in metallic heterostructures. In particular, we consider an alternative spin dissipation channel due to a finite exchange…

Materials Science · Physics 2023-06-14 Quentin Remy

Using a nonlinear mean-field solar dynamo model, we study relationships between the amplitude of the `extended' mode of migrating zonal flows (`torsional oscillations') and magnetic cycles, and investigate whether properties the torsional…

Solar and Stellar Astrophysics · Physics 2020-09-02 V. V. Pipin , A. G. Kosovichev

Within the framework of the covariant formulation of Light-Front Dynamics, we develop a nonperturbative renormalization scheme in the fermion model supposing that the composite fermion is a superposition of the "bare" fermion and a…

High Energy Physics - Theory · Physics 2009-11-10 V. A. Karmanov , J. -F. Mathiot , A. V. Smirnov

Convection driven geodynamo models in rotating spherical geometry have regimes in which reversals occur. However, reversing dynamo models are usually found in regimes where the kinetic and magnetic energy is comparable, so that inertia is…

Geophysics · Physics 2025-01-22 Chris Jones , Yue-Kin Tsang

In this article we summarize and describe the recently found transforms for theories of connections modulo gauge transformations associated with compact gauge groups. Specifically, we put into a coherent picture the so-called loop…

General Relativity and Quantum Cosmology · Physics 2011-04-15 Thomas Thiemann

We studied dynamical balances in magnetorotational instability (MRI) turbulence with a net vertical field in the shearing box model of disks. Analyzing the turbulence dynamics in Fourier (${\bf k}$-)space, we identified three types of…

Solar and Stellar Astrophysics · Physics 2018-11-21 D. Gogichaishvili , G. Mamatsashvili , W. Horton , G. Chagelishvili

In a recent paper (Phys. Rev. Lett. 94 (2005), 184506; physics/0411050) it was shown that a simple mean-field dynamo model with a spherically symmetric helical turbulence parameter alpha can exhibit a number of features which are typical…

Geophysics · Physics 2007-05-23 Frank Stefani , Gunter Gerbeth , Uwe Guenther , Mingtian Xu

Vertically stratified shearing box simulations of magnetorotational turbulence commonly exhibit a so-called butterfly diagram of quasi-periodic azimuthal field reversals. However, in the presence of hydrodynamic convection, field reversals…

High Energy Astrophysical Phenomena · Physics 2017-03-22 Matthew S. B. Coleman , Evan Yerger , Omer Blaes , Greg Salvesen , Shigenobu Hirose

In this work we study the cancellation of non-perturbative anomalies of gravitational theories with gauge group $\mathbb{Z}_k$ in six dimensions. These subtle anomalies require a classification of deformation classes of manifolds with…

High Energy Physics - Theory · Physics 2025-04-07 Markus Dierigl , Michelangelo Tartaglia

The existence and spatio-temporal patterns of $2\pi$-periodic solutions to second order reversible equivariant autonomous systems with commensurate delays are studied using the Brouwer $O(2) \times \Gamma \times \mathbb Z_2$-equivariant…

Dynamical Systems · Mathematics 2020-08-18 Zalman Balanov , Norimichi Hirano , Wieslaw Krawcewicz , Fangfang Liao , Adrian Murza

We construct a class of fixed-time models in which the commutations relations of a Dirac field with a bosonic field are non-trivial and depend on the choice of a given distribution ("twisting factor"). If the twisting factor is fundamental…

Mathematical Physics · Physics 2024-11-06 Ezio Vasselli

The magnetic structures which endow TbMnO$_3$ with its multiferroic properties have been reassessed on the basis of a comprehensive soft x-ray resonant scattering (XRS) study. The selectivity of XRS facilitated separation of the various…

We study the 2D massive fields in the presence of moving mirrors. We do that for standing mirror and mirror moving with constant velocity. We calculate the modes and commutation relations of the field operator with the corresponding…

High Energy Physics - Theory · Physics 2018-11-08 Lev Astrakhantsev , Oleksandr Diatlyk

The generalized tight-binding model, based on the subenvelope functions of distinct sublattices, is developed to investigate the magnetic quantization in sliding bilayer graphenes. The relative shift of two graphene layers induces a…

Materials Science · Physics 2016-11-18 Yao-Kung Huang , Szu-Chao Chen , Yen-Hung Ho , Chiun-Yan Lin , Ming-Fa Lin

Increasing evidence is becoming available about not only the surface differential rotation of rapidly rotating cool stars but, in a small number of cases, also about temporal variations, which possibly are analogous to the solar torsional…

Astrophysics · Physics 2009-11-10 E. Covas , D. Moss , R. Tavakol

We present a study of several systems in which a large scale field is generated over a turbulent background. These large scale fields usually break a symmetry of the forcing by selecting a direction. Under certain conditions, the large…

Fluid Dynamics · Physics 2015-05-27 Basile Gallet , Johann Herault , Claude Laroche , François Pétrélis , Stéphan Fauve

Non-linear electrodynamics arising in the frames of field theories in noncommutative space-time is examined on the base of quaternion formalism. The problem of form-invariance of the corresponding nonlinear constitutive relations governed…

Mathematical Physics · Physics 2011-09-09 V. M. Red'kov , E. A. Tolkachev

We present a new mechanism for oscillatory or random reversals of the magnetic field that occur from a stationary dynamo state. The basic ingredient is the existence of two nearly critical dynamo eigenmodes, a stable and an unstable one,…

Geophysics · Physics 2008-10-29 F. Petrelis , S. Fauve

We propose a novel strategy for the perturbative resummation of transverse momentum-dependent (TMD) observables, using the $q_T$ spectra of gauge bosons ($\gamma^*$, Higgs) in $pp$ collisions in the regime of low (but perturbative)…

High Energy Physics - Phenomenology · Physics 2018-05-23 Daekyoung Kang , Christopher Lee , Varun Vaidya

In the context of non-commutative geometries, we develop a group Fourier transform for the Lie group SU(2). Our method is based on the Schwinger representation of the Lie algebra su(2) in terms of spinors. It allows us to prove that the…

General Relativity and Quantum Cosmology · Physics 2013-05-30 Maité Dupuis , Florian Girelli , Etera R. Livine