相关论文: On the rigidity from infinity for nonlinear Alfv\'…
The role of magnetic helicity is investigated in kinetic Alfv\'en wave and oblique whistler turbulence in presence of a relatively intense external magnetic field $b_0 {\bf e_\parallel}$. In this situation, turbulence is strongly…
We explore superradiance for Alfv\'en waves (Alfv\'enic superradiance) in an axisymmetric rotating magnetosphere of a Kerr black hole within the force-free approximation. On the equatorial plane of the Kerr spacetime, the Alfv\'en wave…
It is widely accepted in the MHD turbulence community that the nonlinear cascade of wave energy requires counter-propagating Alfv\'enic wave-packets, along some mean magnetic field. This fact is an obvious outcome of the MHD equations under…
We study symmetric systems with dissipative boundary conditions. The solutions of the mixed problems for such systems are given by a contraction semigroup $V(t)f = e^{tG_b}f, t \geq 0$. The solutions $u(t, x) = V(t)f$, where $f$ is an…
We perform nonlinear general relativistic ideal magnetohydrodynamic simulations of poloidal magnetic fields in rotating polytropic neutron stars. We have three primary goals: i) to understand the nature of magnetohydrodynamic instabilities…
It is shown that low-collisionality plasmas cannot support linearly polarized shear-Alfv\'en fluctuations above a critical amplitude $\delta B_{\perp}/B_{0} \sim \beta^{\,-1/2}$, where $\beta$ is the ratio of thermal to magnetic pressure.…
A two-field Hamiltonian gyrofluid model for kinetic Alfv\'en waves retaining ion finite Larmor radius corrections, parallel magnetic field fluctuations and electron inertia, is used to study turbulent cascades from the MHD to the sub-ion…
In this paper, we revisit the governing equations for linear magnetohydrodynamic (MHD) waves and instabilities existing within a magnetized, plane-parallel, self-gravitating slab. Our approach allows for fully non-uniformly magnetized…
This paper is devoted to the study of the gravitational instability of a medium permeated by a uniform magnetic field along which a circularly polarized Alfven wave propagates. We concentrate on the case of perturbations purely transverse…
Nonlinear diffusion equations of spectral transfer are systematically derived for anisotropic magnetohydrodynamics in the regime of wave turbulence. The background of the analysis is the asymptotic Alfv\'en wave turbulence equations from…
The parametric decay of finite-size Alfv\'en waves in nonperiodic low-beta plasmas is investigated using one-dimensional hybrid simulations. Compared with the usual small periodic system, a wave packet in a large system under the absorption…
The cut-off of the Alfven wave, caused by plasma collisions with neutrals in multi-component partially ionized plasmas, is discussed. Full multi-component theory is used, and similarities and differences regarding the classic…
Using a two-fluid approach, we consider the properties of relativistically nonlinear (arbitrary $a_0$), circularly polarized \EM\ waves propagating along magnetic field in electron-ion and pair plasmas. Dispersion relations depend on how…
Large-amplitude Alfv\'en waves are subject to parametric decays which can have important consequences in space, astrophysical, and fusion plasmas. Though the Alfv\'en wave parametric decay instability was predicted decades ago,…
When magnetic energy density is much larger than that of matter, as in pulsar/black hole magnetospheres, the medium becomes force-free and we need relativity to describe it. As in non-relativistic magnetohydrodynamics (MHD), Alfv\'enic MHD…
It is often asserted or implicitly assumed, without justification, that the results of two-dimensional investigations of plasma turbulence are applicable to the three-dimensional plasma environments of interest. A projection method is…
We combine theories of scattering for linearized water waves and flexural waves in thin plates to characterize and achieve control of water wave scattering using floating plates. This requires manipulating a sixth-order partial differential…
Physical problems with a solution that can be expressed analytically are scarce; this holds even more true for problems set in a cosmological context. Such solutions are, however, invaluable tools for making comparisons between theory,…
We investigate numerically the dynamics of two-dimensional Euler and ideal magnetohydrodynamics (MHD) flows in systems with a finite number of modes, up to $4096^2$, for which several quadratic invariants are preserved by the truncation and…
The nature of fast magnetoacoustic and Alfv\'en waves is investigated in a zero $\beta$ plasma in the neighbourhood of a pair of two-dimensional null points. This gives an indication of wave propagation in the low $\beta$ solar corona, for…