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Related papers: Small-scale dynamo with finite correlation times

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We consider the evolution of arbitrarily large perturbations of a prescribed pure hydrodynamical flow of an electrically conducting fluid. We study whether the flow perturbations as well as the generated magnetic fields decay or grow with…

Fluid Dynamics · Physics 2021-05-04 Itzhak Fouxon , Joshua Feinberg , Michael Mond

We develop the Kazantsev theory of small-scale dynamo generation at small Prandtl numbers near the generation threshold and restore the concordance between the theory and numerical simulations: the theory predicted a power-law decay below…

Fluid Dynamics · Physics 2026-03-04 A. V. Kopyev , V. A. Sirota , A. S. Il'yn , K. P. Zybin

The conventional theory of small-scale magnetic field generation in a turbulent flow considers time-reversible random flows. However, real turbulent flows are known to be time irreversible: the presence of energy cascade is an intrinsic…

Fluid Dynamics · Physics 2023-12-20 A. V. Kopyev , A. S. Il'yn , V. A. Sirota , K. P. Zybin

D.J. Evans, et al., [Phys. Rev. Lett. 71, 2401 (1993)] discovered a relation, subsequently known as the Fluctuation Theorem (FT), which quantifies the probability of observing fluctuations violating the second law of thermodynamics in…

Statistical Mechanics · Physics 2017-05-19 A. Y. Gorobets , J. M. Borrero , S. Berdyugina

The long time dynamics of large particles trapped in two inhomogeneous turbulent shear flows is studied experimentally. Both flows present a common feature, a shear region that separates two colliding circulations, but with different…

Fluid Dynamics · Physics 2016-03-02 N Machicoane , M López-Caballero , L Fiabane , J-F Pinton , M Bourgoin , J Burguete , R Volk

Many polyatomic astrophysical plasmas are compressible and out of chemical and thermal equilibrium, introducing a bulk viscosity into the plasma via the internal degrees of freedom of the molecular composition, directly impacting the decay…

Astrophysics of Galaxies · Physics 2025-09-10 James R. Beattie , Christoph Federrath , Neco Kriel , Justin Kin Jun Hew , Amitava Bhattacharjee

We consider fluctuations of the dissipated energy in nonlinear driven diffusive systems subject to bulk dissipation and boundary driving. With this aim, we extend the recently-introduced macroscopic fluctuation theory to nonlinear driven…

Statistical Mechanics · Physics 2013-10-29 P. I. Hurtado , A. Lasanta , A. Prados

We give rigorous analytical results on the temporal behavior of two-point correlation functions --also known as dynamical response functions or Green's functions-- in closed many-body quantum systems. We show that in a large class of…

Quantum Physics · Physics 2020-03-20 Álvaro M. Alhambra , Jonathon Riddell , Luis Pedro García-Pintos

We investigate the linear evolution of Richtmyer-Meshkov (RM) instability in the framework of an ideal two-fluid plasma model. The two-fluid plasma equations of motion are separated into a base state and a set of linearized equations…

Plasma Physics · Physics 2022-03-14 Yuan Li , Abeer Bakhsh , Ravi Samtaney

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

We apply the macroscopic fluctuation theory (MFT) to study the large-scale dynamical properties of Brownian particles with arbitrary pairwise interaction. By combining it with standard results of equilibrium statistical mechanics for the…

Statistical Mechanics · Physics 2026-05-19 Aurélien Grabsch , Davide Venturelli , Olivier Bénichou

This study shows the connection between three previously observed but seemingly unrelated phenomena in hydrodynamic (HD) and magnetohydrodynamic (MHD) turbulent flows, involving the emergence of fluctuations occurring on very long time…

Fluid Dynamics · Physics 2015-05-28 P. Dmitruk , P. D. Mininni , A. Pouquet , S. Servidio , W. H. Matthaeus

Perhaps the most basic question we can ask about cosmological correlations is how their strength changes as we smoothly vary kinematic parameters. The answer is encoded in differential equations that govern this evolution in kinematic…

High Energy Physics - Theory · Physics 2023-12-12 Nima Arkani-Hamed , Daniel Baumann , Aaron Hillman , Austin Joyce , Hayden Lee , Guilherme L. Pimentel

Following on our previous work [S. Delong and B. E. Griffith and E. Vanden-Eijnden and A. Donev, Phys. Rev. E, 87(3):033302, 2013], we develop temporal integrators for solving Langevin stochastic differential equations that arise in…

Statistical Mechanics · Physics 2015-06-23 S. Delong , Y. Sun , B. E. Griffith , E. Vanden-Eijnden , A. Donev

We obtain an implicit equation for the correlation dimension of dynamical systems in terms of an integral over a propagator. We illustrate the utility of this approach by evaluating the correlation dimension for inertial particles suspended…

Fluid Dynamics · Physics 2015-05-14 Michael Wilkinson , Bernhard Mehlig , Kristian Gustavsson

We present an approach for the description of fluctuations that are due to finite system size induced correlations in the Kuramoto model of coupled oscillators. We construct a hierarchy for the moments of the density of oscillators that is…

Chaotic Dynamics · Physics 2009-11-11 Eric J. Hildebrand , Michael A. Buice , Carson C. Chow

Decay of honeycomb-generated turbulence in a duct with a static transverse magnetic field is studied via direct numerical simulations. The simulations follow the revealing experimental study of Sukoriansky et al. (1986), in particular the…

Fluid Dynamics · Physics 2019-05-01 Oleg Zikanov , Dmitry Krasnov , Thomas Boeck , Semion Sukoriansky

We obtained self-similar solutions of relativistically expanding magnetic loops by assuming axisymmetry and a purely radial flow. The stellar rotation and the magnetic fields in the ambient plasma are neglected. We include the Newtonian…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Hiroyuki R. Takahashi , Eiji Asano , Ryoji Matsumoto

The diffusive dynamics of a particle in a medium with space-dependent friction coefficient is studied within the framework of the inertial Langevin equation. In this description, the ambiguous interpretation of the stochastic integral,…

Statistical Mechanics · Physics 2015-06-16 Oded Farago , Niels Grønbech-Jensen

The amplification of magnetic fields is crucial for understanding the observed magnetization of stars and galaxies. Turbulent dynamo is the primary mechanism responsible for that but the understanding of its action in a collapsing…

Astrophysics of Galaxies · Physics 2026-04-22 Muhammed Irshad P , Pallavi Bhat , Kandaswamy Subramanian , Anvar Shukurov