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1.
We present the derivation of the hydrodynamic limit under Eulerian scaling for a general class of one-dimensional interacting particle systems with two or more conservation laws. Following Yau's relative entropy method it turns out that in case of more than one conservation laws, in order that the system exhibit hydrodynamic behaviour, some particular identities reminiscent of Onsager's reciprocity relations must hold. We check validity of these identities whenever a stationary measure with product structure exists. It also follows that, as a general rule, the equilibrium thermodynamic entropy (as function of the densities of the conserved variables) is a globally convex Lax entropy of the hyperbolic systems of conservation laws arising as hydrodynamic limit. As concrete examples we also present a number of models modeling deposition (or domain growth) phenomena. The Onsager relations arising in the context of hydrodynamic limits under hyperbolic scaling seem to be novel. The fact that equilibrium thermodynamic entropy is Lax entropy for the arising Euler equations was noticed earlier in the context of Hamiltonian systems with weak noise, see ref. 7.  相似文献   

2.
The conserved quantities for the heated radial liquid jet and the heated radial free jet are established by using conservation laws. The flow in a heated radial jet is described by Prandtl's momentum boundary layer equation, the continuity equation and the energy equation. Viscous dissipation is neglected. The multiplier approach is used to derive the conservation laws for the system of three equations for the velocity components and the temperature and three conserved vectors are obtained. The conservation laws for the system of two partial differential equations for the stream function formulation are also computed by the multiplier approach and three conserved vectors are obtained. One of these is a non-local conserved vector for the system. The conserved quantities for the heated radial liquid jet and the heated radial free jet, emitted into a stationary fluid of uniform temperature θ, are derived by integrating the conservation laws across the jet.  相似文献   

3.
In this paper we investigate the semi-discrete Ablowitz–Kaup–Newell–Segur (sdAKNS) hierarchy, and specifically their Lax pairs and infinitely many conservation laws, as well as the corresponding continuum limits. The infinitely many conserved densities derived from the Ablowitz-Ladik spectral problem are trivial, in the sense that all of them are shown to reduce to the first conserved density of the AKNS hierarchy in the continuum limit. We derive new and nontrivial infinitely many conservation laws for the sdAKNS hierarchy, and also the explicit combinatorial relations between the known conservation laws and our new ones. By performing a uniform continuum limit, the new conservation laws of the sdAKNS system are then matched with their counterparts of the continuous AKNS system.  相似文献   

4.
Interfaces moving in a disordered medium exhibit stochastic velocity fluctuations obeying universal scaling relations related to the presence or absence of conservation laws. For fluid invasion of porous media, we show that the fluctuations of the velocity are governed by a geometry-dependent length scale arising from fluid conservation. This result is compared to the statistics resulting from a nonequilibrium (depinning) transition between a moving interface and a stationary, pinned one.  相似文献   

5.
Gravitationphysics and Lorentz-space Coordinate invariant conservation laws for static and stationary gravitation fields can be formulated. Being seen as elements of Lorentz space the quantities to be conserved open to a physical interpretation. These quantities are field and matter terms. Some examples illustrate how useful this approach has turned out to be.  相似文献   

6.
A system of equations describing supersonic gas flow in the presence of a heat source near the shock front is obtained. Relations between the gas parameters in disturbed and undisturbed regions, which generalize the classical Hugoniot-Rankine relations, are derived. Formulas for calculation of the flow parameters in the presence of an energy supply to the shock layer region are presented. It is demonstrated that there exists a critical intensity of energy supply at which the system of equations of the conservation laws for the gas parameters on both sides of the shock layer possesses no stationary solution.  相似文献   

7.
The self-dual Yang-Mills field theories in two-dimensional representations are formulated. The Biicklund transformation and the conservation law are given in the framework of the prolongation theory. Furthermore, we derive the conserved current algebras which are in essence the Yang-Baxter relations.  相似文献   

8.
Time evolutions of the Toda lattice hierarchies of Ueno and Takasaki are induced by Hamiltonians which are conservation laws for the original (one and two dimensional) Toda lattice obtained by Olive and Turok. Moreover these Hamiltonians for two dimensional Toda lattice hierarchy are also conserved quantities of the two component KP hierarchy in which that system is embedded. The one dimensional Toda lattice hierarchy is characterized by the bilinear relations, and a new version of the one dimensional Toda lattice hierarchy is constructed. Generalized Toda lattice hierarchies associated to all affine Lie algebras are presented.  相似文献   

9.
An algebraic block-diagonalization of the Dirac Hamiltonian in a time-independent external field reveals a charge-index conservation law which forbids the physical phenomena of the Klein paradox type and guarantees a single-particle nature of the Dirac equation in strong external fields. Simultaneously, the method defines simpler quantum-mechanical objects—paulions and antipaulions, whose 2-component wave functions determine the Dirac electron states through exact operator relations. Based on algebraic symmetry, the presented theory leads to a new understanding of the Dirac equation physics, including new insight into the Dirac measurements and a consistent scheme of relativistic quantum mechanics of electron in the paulion representation. Along with analysis of the mathematical anatomy of the Klein paradox falsity, a complete set of paradox-free eigenfunctions for the Klein problem is obtained and investigated via stationary solutions of the Pauli-like equations with respective paulion Hamiltonians. It is shown that the physically correct Dirac states in the Klein zone are characterized by the total particle reflection from the potential step and satisfy the fundamental charge-index conservation law.  相似文献   

10.
We investigate the harmonic chain forced by a multiplicative noise, the evolution is given by an infinite system of stochastic differential equations. Total energy and deformation are preserved, the conservation of momentum is destroyed by the noise. Gaussian product measures are the extremal stationary states of this model. Equilibrium fluctuations of the conserved fields at a diffusive scaling are described by a couple of generalized Ornstein-Uhlenbeck processes. 1991 Mathematics Subject Classification: Primary 60K31, secondary 82C22 Partially supported by Hungarian Science Foundation Grant T37685, the European Science Foundation Project RDSES, and by the ACI-NIM 168 ‘Transport hors équilibre.’  相似文献   

11.
傅双双  骆顺龙  孙源 《物理学报》2019,68(3):30301-030301
自量子力学诞生以来,相干性和互补性一直是被广泛而深入研究的两个重要课题.随着量子信息近年来的发展,人们引入了若干度量来定量地刻画相干性和互补性.本文建立两个信息守恒关系式,分别基于"Bures距离-保真度"和"对称-非对称",并且利用它们来刻画相干性和互补性.具体来说,首先从信息守恒的观点解释Bures距离和保真度的互补关系,并由此自然推导出Mach-Zehnder干涉仪中的Englert"干涉-路径"互补关系.其次在量子态和信道相互作用的一般框架中讨论"对称-非对称"信息守恒关系,并揭示其与Bohr互补性和量子相干性的内在联系.最后,在Mach-Zehnder干涉仪中探讨相干、退相干及互补性,刻画两个信息守恒关系之间的密切联系.  相似文献   

12.
The Fokker–Planck equation associated with the two-dimensional stationary Schrödinger equation has the conservation law form that yields a pair of potential equations. The special form of Darboux transformation of the potential equations system is considered. As the potential variable is a nonlocal variable for the Schrödinger equation that provides the nonlocal Darboux transformation for the Schrödinger equation. This nonlocal transformation is applied for obtaining of the exactly solvable two-dimensional stationary Schrödinger equations. The examples of exactly solvable two-dimensional stationary Schrödinger operators with smooth potentials decaying at infinity are obtained.  相似文献   

13.
周光召  苏肇冰 《物理学报》1981,30(3):401-409
本文是我们从微观量子统计理论出发讨论非平衡统计定常态的时间反演对称性质的第二部份。本文应用文献的结果对非平衡统计定常态的普遍性质进行较为系统的讨论。对于具有时间反演对称的非平衡统计定常态,证明了广义(自由能)势函数的存在性;导出了涨落耗散定理的Rayleigh-Jeans极限形式;推广了局部热平衡假设下的Onsager倒易关系;导得了序参量-守恒荷密度普遍方程(TDGL)的“可逆-不可逆”运动分解形式。  相似文献   

14.
The rationale for designing atmospheric numerical model dynamical cores with certain conservation properties is reviewed. The conceptual difficulties associated with the multiscale nature of realistic atmospheric flow, and its lack of time-reversibility, are highlighted. A distinction is made between robust invariants, which are conserved or nearly conserved in the adiabatic and frictionless limit, and non-robust invariants, which are not conserved in the limit even though they are conserved by exactly adiabatic frictionless flow. For non-robust invariants, a further distinction is made between processes that directly transfer some quantity from large to small scales, and processes involving a cascade through a continuous range of scales; such cascades may either be explicitly parameterized, or handled implicitly by the dynamical core numerics, accepting the implied non-conservation. An attempt is made to estimate the relative importance of different conservation laws. It is argued that satisfactory model performance requires spurious sources of a conservable quantity to be much smaller than any true physical sources; for several conservable quantities the magnitudes of the physical sources are estimated in order to provide benchmarks against which any spurious sources may be measured.  相似文献   

15.
The problem of conservation of magnitudes is considered for a vortex in a relaxing compressible medium. Heat release due to the relaxation of a nonequilibrium medium leads to the propagation of compression waves, which remove material. Traditional integrals of motion are inapplicable in this case. We pro-pose the concept of integral quantity, which is conserved with an arbitrary degree of accuracy despite the fact that waves cross the boundary of the integration domain. Based on this concept, a broad class of conservation laws is derived for axisymmetric disturbances of columnar vortices, including conservation of the circulation and total angular momentum of the vortex. For nonaxisymmetric disturbances, it is shown that the total angular momentum and properly defined energy integral are conserved. Numerical verification of the derived conservation laws is performed and the perspectives for using these conservation laws in numerical simulations are discussed.  相似文献   

16.
Several algebraic characterizations of vacuum type III metric fields are discussed. A covariant integral conservation law is obtained by introducing a divergence free vector density that is uniquely determined by the metric and Riemann tensors of a type III metric. In a region where the gravitational field is of type III almost everywhere, the vector density vanishes at a point if and only if the Riemann tensor vanishes there. The conserved quantity has the dimensions of energy but is probably not simply related to energy in the ordinary sense. The conservation law is interpreted as aHuyghen's principle for an intensity measured by measuring the relative accelerations due to the gravitational field. It is compared to a previously derived action conservation law for a classical, general relativistic electromagnertic field and with a covariant action conservation law that is valid in null (degeneate type II) metrics. Further propagation laws for null and type III waves are given under the assumption that the wave vector is hypersurface orthogonal. It is shown that in linear approximation the far and semi-far fields of a radiating quadrupole are null and type III respectively; the form of the conservation laws in these linearized metrics is discussed. In an appendix a “strongly” conserved form of the tensor ofBel andRobinson is suggested.  相似文献   

17.
The stationary condition is derived taking into account the polarization of radiation in the general case of a scattering inhomogeneous medium in an arbitrary-shape emitter. The necessary stationary condition for an emitter in which radiation is emitted and extinguished simultaneously is complete extinction of the entire emitted radiation. Radiation extinction as a result of absorption by the medium and the emergence of radiation from the emitter is analyzed. The stationary condition is an analytical form of writing that extinction of radiation is a sure event whose probability is equal to unity. The passage of radiation through the medium is described on the basis of the linear transport theory with the help of the matrices of the Green functions. The stationary condition includes the characteristics of polarized radiation extinction of which is analyzed, the absorption coefficients of the medium, and the elements of the matrices of the Green functions, which are determined by optical and geometrical parameters of the emitter. The stationary condition obtained is used for deriving the relations between the components of scalar intensity observed in an arbitrary region of the emitter. These relations include, in addition to the absorption coefficients and the matrix elements of the Green functions, the powers of the primary radiation. Possible applications of the stationary condition and the relations between intensity components in computations and experimental studies are considered.  相似文献   

18.
The dynamical equations of relativistic quantum mechanics prescribe the motion of wave packets for sets of events which trace out the world lines of the interacting particles. Electromagnetic theory suggests thatparticle world line densities be constructed from concatenation of event wave packets. These sequences are realized in terms of conserved probability currents. We show that these conserved currents provide a consistent particle and antiparticle interpretation for the asymptotic states in scattering processes. The relation between current conservation and unitarity is used to establish relations between pair production and annihilation amplitudes and scattering. The discrete symmetriesC, T, P are studied and it is shown that no Dirac sea (for fermions where such a construction is possible, or bosons where it is not) is required for consistency of the theory. These currents, furthermore, represent the discrete symmetries in a way consistent with their interpretation as particle currents.This work was supported in part by the Binational Science Foundation (BSF), Jerusalem, Israel. A preliminary report was given at the Conference on Statistical Mechanics and Irreversible Processes, San Antonio, Texas, March 14–17, 1982.The first two authors dedicate this paper to the memory of their friend and colleague, Yeshiahu (Ishi) Lavie, who died in the service of the Israel Defense Forces, January 2, 1983.  相似文献   

19.
In the presence of symmetries, conserved quantities can be obtained by contracting the stress-energy tensor with a Killing vector. We generalize this result to piecewise Killing vectors by giving sufficient conditions for the construction of an associated conserved quantity. A typical example, namely, two stationary space-times joined together in such a way that the resulting space-time is not stationary, is treated in detail.  相似文献   

20.
Applying Parikh's quantum tunneling method, the tunneling characteristics of stationary Kaluza-Klein black hole is researched. The result shows that the tunneling rate across the event horizon of the black hole is relevant to the change of Bekenstein-Hawking entropy and the derived radiation spectrum deviates from pure thermal when the self-gravitation, energy conservation and angular momentum conservation are taken into consideration. Finally, we use the obtained results to reduce to stationary Kerr black hole and static Swarzschild black hole, and find that only ignoring the spectrum at higher energies the tunneling radiation spectrum is consistent with Hawking pure thermal one. PACS:97.60.Lf,04.70._s  相似文献   

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