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1.
Classical solutions of the relativistic Vlasov–Maxwell system are considered, describing a collisionless plasma with two species of particles. ions and electrons. It is shown that as the ion mass m tends to infinity, the corresponding solution of the relativistic Vlasov–Maxwell system tends to the solution of a system, in which the ions are given by a fixed ion background and only the electrons move. The convergence is uniform on compact time intervals, with an asymptotic convergence rate of m?1.  相似文献   

2.
We study stationary solutions of the relativistic Vlasov–Maxwell system of plasma physics which have a special form introduced (in the classical setting) by Rudykh, Sidorov and Sinitsy and establish their existence under suitable assumptions on the ansatz functions. © 1997 by B. G. Teubner Stuttgart–John Wiley & Sons Ltd. Math. Meth. Appl. Sci., Vol. 20, 667–677 (1997).  相似文献   

3.
We consider a collisionless plasma, which consists of electrons and positively charged ions and is confined to a bounded domain in ?3. The distribution functions of the particles are assumed to satisfy specular reflections on the boundary of the domain and the boundary is assumed to be perfectly conducting. We establish the existence of stationary plasmas in the non-relativistic, electrostatic case described by the Vlasov–Poisson system as well as in the relativistic, electrodynamic case described by the relativistic Vlasov–Maxwell system.  相似文献   

4.
A collisionless plasma is modelled by the Vlasov–Maxwell system. In the presence of very large velocities, relativistic corrections are meaningful. When magnetic effects are ignored this formally becomes the relativistic Vlasov–Poisson equation. The initial datum for the phase space density ƒ0(x, v) is assumed to be sufficiently smooth, non‐negative and cylindrically symmetric. If the (two‐dimensional) angular momentum is bounded away from zero on the support of ƒ0(x, v), it is shown that a smooth solution to the Cauchy problem exists for all times. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

5.
In this paper, we investigate the continuous dependence with respect to the initial data of the solutions for the 1D and 1.5D relativistic Vlasov–Maxwell system. More precisely, we prove that these solutions propagate with finite speed. We formulate our results in the framework of mild solutions, i.e., the particle densities are solutions by characteristics and the electro-magnetic fields are Lipschitz continuous functions.  相似文献   

6.
We study here the behavior of weak solutions for the relativistic stationary Vlasov–Maxwell system with boundary conditions in a three-dimensional bounded domain with strictly star-shaped boundary, when the light speed becomes infinite. We prove the convergence toward a weak solution for the stationary Vlasov–Poisson system. The time periodic problem and the problem with initial-boundary conditions can be treated by the same method. To cite this article: M. Bostan, C. R. Acad. Sci. Paris, Ser. I 340 (2005).  相似文献   

7.
We study the 1D Vlasov–Maxwell system with time‐periodic boundary conditions in its classical and relativistic form. We are mainly concerned with existence of periodic weak solutions. We shall begin with the definitions of weak and mild solutions in the periodic case. The main mathematical difficulty in dealing with the Vlasov–Maxwell system consist of establishing L estimates for the charge and current densities. In order to obtain this kind of estimates, we impose non‐vanishing conditions for the incoming velocities, which assure a finite lifetime of all particles in the computational domain ]0,L[. The definition of the mild solution requires Lipschitz regularity for the electro‐magnetic field. It would be enough to have a generalized flow but the result of DiPerna Lions (Invent. Math. 1989; 98 : 511–547) does not hold for our problems because of boundary conditions. Thus, in the first time, the Vlasov equation has to be regularized. This procedure leads to the study of a sequence of approximate solutions. In the same time, an absorption term is introduced in the Vlasov equation, which guarantees the uniqueness of the mild solution of the regularized problem. In order to preserve the periodicity of the solution, a time‐averaging vanishing condition of the incoming current is imposed: \def\d{{\rm d}}\def\incdist#1#2{\int_{0}^{T}\d t\int_{v_{x}#10}\int_{v_{y}}v_xg_{#2}(t,v_x,v_y)\,\d v}$$\incdist{>}{0}+\incdist{<}{L}=0$$\nopagenumbers\end (1) where g0, gL are incoming distributors (2) (3) The existence proof uses the Schauder fixed point theorem and also the velocity averaging lemma of DiPerna and Lions (Comm. Pure Appl. Math. 1989; XVII : 729–757). In the last section we treat the relativistic case. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

8.
An approximation for the relativistic Vlasov-Maxwell (RVM) system of partial differential equations in the one-space, two-momenta case is proposed. The speed of light, c, appears as a parameter in this system. The approximation is obtained by modifying certain integral operators appearing in integral representations, due to Glassey and Strauss, of the electric and magnetic fields, and replaces the hyperbolic Maxwell system with one that is elliptic in nature (for each fixed t). Solutions of the modified problem are shown to converge in a pointwise sense to solutions of (RVM) at the asymptotic rate of 1/c2 as c tends to infinity.  相似文献   

9.
We discuss the connection between different scalings limits of the quantum-relativistic Dirac–Maxwell system. In particular we give rigorous results for the quasi-neutral/non-relativistic limit of the Vlasov–Maxwell system: we obtain a magneto-hydro-dynamic system when we consider the magnetic field as a non-relativistic effect and we obtain the Euler equation when we see it as a relativistic effect. A mathematical key is the modulated energy method. To cite this article: Y. Brenier et al., C. R. Acad. Sci. Paris, Ser. I 334 (2002) 239–244.  相似文献   

10.
We consider the Cauchy problem for the Vlasov–Maxwell–Fokker–Planck system in the plane. It is shown that for smooth initial data, as long as the electromagnetic fields remain bounded, then their derivatives do also. Glassey and Strauss have shown this to hold for the relativistic Vlasov–Maxwell system in three dimensions, but the method here is totally different. In the work of Glassey and Strauss, the relativistic nature of the particle transport played an essential role. In this work, the transport is nonrelativistic, and smoothing from the Fokker–Planck operator is exploited. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

11.
In (Arch. Rat. Mech. Anal. 1986; 92:59–90), Glassey and Strauss showed that if the growth in the momentum of the particles is controlled, the relativistic Vlasov–Maxwell system has classical solution globally in time. Later they proved that such control is achieved if the kinetic energy density of the particles remains bounded for all time (Math. Meth. Appl. Sci. 1987; 9:46–52). Here, we show that the latter assumption can be weakened to the boundedness of the spatial density. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

12.
We prove the global existence of weak solutions to the Vlasov–Darwin system in R3 for small initial data. The Vlasov–Darwin system is an approximation of the Vlasov–Maxwell model which is valid when the characteristic speed of the particles is smaller than the light velocity, but not too small. In contrast to the Vlasov–Maxwell system, the total energy conservation does not provide an L2‐bound on the transverse part of the electric field. This difficulty may be overcome by exploiting the underlying elliptic structure of the Darwin equations under a smallness assumption on the initial data. We finally investigate the convergence of the Vlasov–Darwin system towards the Vlasov–Poisson system. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

13.
《偏微分方程通讯》2013,38(7):957-985
ABSTRACT

We study the Nordström–Vlasov system, which describes the dynamics of a self-gravitating ensemble of collisionless particles in the framework of the Nordström scalar theory of gravitation. If the speed of light c is considered as a parameter, it is known that in the Newtonian limit c → ∞ the Vlasov–Poisson system is obtained. In this paper we determine a higher approximation and establish a pointwise error estimate of order 𝒪(c ?4). Such an approximation is usually called a 1.5 post-Newtonian approximation.  相似文献   

14.
15.
We prove the nonlinear stability or instability of certain periodic equilibria of the 1½D relativistic Vlasov‐Maxwell system. In particular, for a purely magnetic equilibrium with vanishing electric field, we prove its nonlinear stability under a sharp criterion by extending the usual Casimir‐energy method in several new ways. For a general electromagnetic equilibrium we prove that nonlinear instability follows from linear instability. The nonlinear instability is macroscopic, involving only the L1‐norms of the electromagnetic fields. © 2006 Wiley Periodicals, Inc.  相似文献   

16.
The derivation of the Vlasov–Maxwell and the Vlasov–Poisson–Poisson equations from Lagrangians of classical electrodynamics is described. The equations of electromagnetohydrodynamics (EMHD) type and electrostatics with gravitation are obtained. We obtain and compare the Lagrange equalities and their generalizations for different types of the Vlasov and EMHD equations. The conveniences of writing the EMHD equations in twice divergent form are discussed. We analyze exact solutions to the Vlasov–Poisson–Poisson equations with the presence of gravitation where we have different types of nonlinear elliptic equations for trajectories of particles with critical mass m 2 = e 2/G, which has an obvious physical sense, where G denotes the gravitation constant and e is the electron charge. As a consequence we have different behaviors of particles: divergence or collapse of their trajectories.  相似文献   

17.
We study a model which describes a Vlasov field E in interacting external electrostatic fields E ex . In the electrostatic case it is possible to prove the existence of the optimal solution for the self-consistent Vlasov–Poisson equation. A new approach to the investigation is based on the property of an universality of Maxwell equations and the first Lyapunov method.  相似文献   

18.
The relativistic Vlasov–Maxwell–Fokker–Planck system is used in modelling distribution of charged particles in plasma. It consists of a transport equation coupled with the Maxwell system. The diffusion term in the equation models the collisions among particles, whereas the viscosity term signifies the dynamical frictional forces between the particles and the background reservoir. In the case of one space variable and two momentum variables, we prove the existence of a classical solution when the initial density decays fast enough with respect to the momentum variables. The solution which shares this same decay condition along with its first derivatives in the momentum variables is unique. © 1998 B. G. Teubner Stuttgart—John Wiley & Sons, Ltd.  相似文献   

19.
In this work, we study the existence of time periodic weak solution for the N‐dimensional Vlasov–Poisson system with boundary conditions. We start by constructing time periodic solutions with compact support in momentum and bounded electric field for a regularized system. Then, the a priori estimates follow by computations involving the conservation laws of mass, momentum and energy. One of the key point is to impose a geometric hypothesis on the domain: we suppose that its boundary is strictly star‐shaped with respect to some point of the domain. These results apply for both classical or relativistic case and for systems with several species of particles. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

20.
We study here the existence of time periodic solution for the Vlasov–Maxwell equations in a three dimensional bounded domain. We assume that the boundary of the domain is strictly star-shaped. We give a priori estimates for the kinetic and electro-magnetic energy, and also for the normal and tangential traces of the electro-magnetic field. This method allows us to treat both classical and relativistic cases. To cite this article: M. Bostan, C. R. Acad. Sci. Paris, Ser. I 339 (2004).  相似文献   

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