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Related papers: Magnetic topology in fluids

200 papers

Magnetic reconnection is a fundamental plasma process that converts magnetic energy into bulk flow energy, thermal energy, and nonthermal particle acceleration. Despite its importance, the statistical properties of the turbulent…

Astrophysics of Galaxies · Physics 2025-12-16 Yue Hu , Luca Comisso , Lorenzo Sironi , Siyao Xu

There is a reformulation of magnetohydrodynamics in which the fundamental dynamical quantities are the positions and velocities of the lines of magnetic flux in the plasma, which turn out to obey equations of motion very much like ideal…

Astrophysics · Physics 2009-10-31 Mattias Christensson , Mark Hindmarsh

A topological flux function is introduced to quantify the topology of magnetic braids: non-zero line-tied magnetic fields whose field lines all connect between two boundaries. This scalar function is an ideal invariant defined on a…

Plasma Physics · Physics 2015-06-15 A. R. Yeates , G. Hornig

Motivated by the notion that the mathematics of gravity can be reproduced from a statistical requirement of maximal entropy, we study the consequence of introducing an entropic source term in the Einstein-Hilbert action. For a spatially…

General Relativity and Quantum Cosmology · Physics 2024-03-20 Soumya Chakrabarti

Turbulence in a conducting plasma can amplify seed magnetic fields in what is known as the turbulent, or small-scale, dynamo. The associated growth rate and emergent magnetic-field geometry depend sensitively on the material properties of…

High Energy Astrophysical Phenomena · Physics 2022-10-17 Alisa K. Galishnikova , Matthew W. Kunz , Alexander A. Schekochihin

Recent fully nonlinear, kinetic three-dimensional simulations of magnetic reconnection [Daughton et al. 2011] evolve structures and exhibit dynamics on multiple scales, in a manner reminiscent of turbulence. These simulations of…

Plasma Physics · Physics 2015-06-15 E. Leonardis , S. C. Chapman , W. Daughton , V. Roytershteyn , H. Karimabadi

Magnetic helicity is an invariant of ideal magnetohydrodynamics (MHD) that encodes information on the topology of magnetic field lines. It has long been appreciated that magnetic topology is an important constraint for the evolution of…

Solar and Stellar Astrophysics · Physics 2020-09-25 David MacTaggart , Chris Prior

We present a simple method to efficiently compute a lower limit of the topological entropy and its spatial distribution for two-dimensional mappings. These mappings could represent either two-dimensional time-periodic fluid flows or…

Plasma Physics · Physics 2017-10-19 Simon Candelaresi , David Ian Pontin , Gunnar Hornig

Kinematic dynamo in incompressible isotropic turbulent flows with high magnetic Prandtl number is considered. The approach interpreting an arbitrary magnetic field distribution as a superposition of localized perturbations (blobs) is…

Fluid Dynamics · Physics 2023-10-26 A. S. Il'yn , A. V. Kopyev , V. A. Sirota , K. P. Zybin

Aims: To investigate the relationship between surges and magnetic reconnection during the emergence of small-scale active regions. In particular, to examine how the large-scale geometry of the magnetic field, shaped by different phases of…

Solar and Stellar Astrophysics · Physics 2015-06-23 David MacTaggart , Salvo Guglielmino , Andrew Haynes , Radostin Simitev , Francesca Zuccarello

We analyze an axisymmetric magnetohydrodynamics configuration, describing the morphology of a purely differentially rotating thin plasma disk, in which linear and non-linear perturbations are triggered associated with microscopic magnetic…

Solar and Stellar Astrophysics · Physics 2018-10-02 Giovanni Montani , Mariachiara Rizzo , Nakia Carlevaro

Random magnetic field configurations are ubiquitous in nature. Such fields lead to a variety of dynamical phenomena, including localization and glassy physics in some condensed matter systems and novel transport processes in astrophysical…

High Energy Physics - Theory · Physics 2024-09-11 Tian-Gang Zhou , Michael Winer , Brian Swingle

This paper is the first in a series aimed at understanding the long-term evolution of neutron star magnetic fields. We model the stellar matter as an electrically neutral and lightly ionized plasma composed of three moving particle species:…

Astrophysics · Physics 2009-11-13 J. Hoyos , A. Reisenegger , J. A. Valdivia

Predicting the final state of turbulent plasma relaxation is an important challenge, both in astrophysical plasmas such as the Sun's corona and in controlled thermonuclear fusion. Recent numerical simulations of plasma relaxation with…

Plasma Physics · Physics 2015-05-11 A. R. Yeates , A. J. B. Russell , G. Hornig

In paper I, we obtained an equation for the evolution of density inhomogeneities in a radiation dominated universe when they are affected by magnetic fields. In this second paper we apply this equation to the case in which the subjacent…

Astrophysics · Physics 2016-08-30 E. Florido , E. Battaner

In this paper, the generation of magnetic fields in a nonuniformly rotating layer of finite thickness of an electrically conducting fluid by thermomagnetic (TM) instability. This instability arises due to the temperature gradient $\nabla…

Fluid Dynamics · Physics 2021-04-23 M. I. Kopp , K. N. Kulik , A. V. Tur , V. V. Yanovsky

In helical hydromagnetic turbulence with an imposed magnetic field (which is constant in space and time) the magnetic helicity of the field within a periodic domain is no longer an invariant of the ideal equations. Alternatively, there is a…

Astrophysics · Physics 2009-11-07 Axel Brandenburg , William H. Matthaeus

In the present work the instability of a flat horizontal thin layer of a magnetic fluid (the depth of no more than 50 \mum) under the action of a uniform magnetic field is studied experimentally. It was revealed that the development of…

Fluid Dynamics · Physics 2017-04-28 Arthur Zakinyan , Levon Mkrtchyan , Yuri Dikansky

This work examines the effect of the embedded magnetic field strength on the non-linear development of the magnetic Rayleigh-Taylor Instability (RTI) (with a field-aligned interface) in an ideal gas close to the incompressible limit in…

Solar and Stellar Astrophysics · Physics 2017-09-20 Jack Carlyle , Andrew Hillier

The nonlinear coupling between spacetime geometry and matter in the early Universe remains a frontier in theoretical cosmology. By introducing a novel gravitomagnetic-hydrodynamic framework, we reveal a fundamental analogy between…

General Relativity and Quantum Cosmology · Physics 2025-10-28 Jiaxiang Liang , Peng Xu , Minghui Du , Yifu Cheng , Zhan Wang , Ziren Luo , Manjia Liang