首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
For asymptotically hyperbolic manifolds of dimension n with scalar curvature at least equal to ?n(n ? 1) the conjectured positive mass theorem states that the mass is non-negative, and vanishes only if the manifold is isometric to hyperbolic space. In this paper we study asymptotically hyperbolic manifolds which are also conformally hyperbolic outside a ball of fixed radius, and for which the positive mass theorem holds. For such manifolds we show that the conformal factor tends to one as the mass tends to zero.  相似文献   

2.
We consider a generalization of the interior Schwarzschild solution that we match to the exterior one to build global C 1 models that can have arbitrary large mass, or density, with arbitrary size. This is possible because of a new insight into the problem of localizing the center of symmetry of the models and the use of principal transformations to understand the structure of space.  相似文献   

3.
4.
5.
This paper extends the model reduction method by the operator projection to the one-dimensional special relativistic Boltzmann equation. The derivation of arbitrary order globally hyperbolic moment system is built on our careful study of two families of the complicate Grad type orthogonal polynomials depending on a parameter. We derive their recurrence relations, calculate their derivatives with respect to the independent variable and parameter respectively, and study their zeros and coefficient matrices in the recurrence formulas. Some properties of the moment system are also proved. They include the eigenvalues and their bound as well as eigenvectors, hyperbolicity, characteristic fields, linear stability, and Lorentz covariance. A semi-implicit numerical scheme is presented to solve a Cauchy problem of our hyperbolic moment system in order to verify the convergence behavior of the moment method. The results show that the solutions of our hyperbolic moment system converge to the solution of the special relativistic Boltzmann equation as the order of the hyperbolic moment system increases.  相似文献   

6.
For an FRW model with a minimally coupled scalar field having hyperbolic(exponential) potential we evaluate the wave function both by solving theWheeler-Dewitt (WD) equation and by evaluating the path integral. The WDequation is solved in configuration as well as in momentum space, while thepath integral is evaluated by dividing the lapse integral into a number of pieces.  相似文献   

7.
Hyperbolic conservation laws with relaxation   总被引:19,自引:0,他引:19  
The effect of relaxation is important in many physical situations. It is present in the kinetic theory of gases, elasticity with memory, gas flow with thermo-non-equilibrium, water waves, etc. The governing equations often take the form of hyperbolic conservation laws with lower-order terms. In this article, we present and analyze a simple model of hyperbolic conservation laws with relaxation effects. Dynamic subcharacteristics governing the propagation of disturbances over strong wave forms are identified. Stability criteria for diffusion waves, expansion waves and traveling waves are found and justified nonlinearly. Time-asymptotic expansion and the energy method are used in the analysis. For dissipative waves, the expansion is similar in spirit to the Chapman-Enskog expansion in the kinetic theory. For shock waves, however, a different approach is needed.The paper was written at Mittag-Leffler Institute; the author wants to thank the Institute for the visiting position in 1986. This work was supported in part by an NSF grant  相似文献   

8.
Hyperbolic Conformal Geometry with Clifford Algebra   总被引:4,自引:0,他引:4  
In this paper, we study hyperbolic conformal geometry following a Clifford algebraic approach. Similar to embedding an affine space into a one-dimensional higher linear space, we embed the hyperboloid model of the hyperbolic n-space in into . The model is convenient for the study of hyperbolic conformal properties. Besides investigating various properties of the model, we also study conformal transformations using their versor representations.  相似文献   

9.
By solving rigorously the relativistic wave equations derived from Bargmann-Wigner equation for arbitrary spin,the relativistic wavefunctions in momentum representation for particles with arbitrary spin are deduced.  相似文献   

10.
Hyperbolic patterns constructed basing on higher derivatives of the hyperbolic tangent represent specially designed sums of even powers of soliton-like excitations. Under certain limitations, the hyperbolic patterns satisfy solutions of an equation which is homomorphic to the Klein-Gordon one. Since the hyperbolic patterns may be considered as mathematical images of wave packets, the problem of de Broglie's double solution is discussed. The hyperbolic patterns can be used to construct spatially localized dynamic structures.  相似文献   

11.
The notions of weak Darboux integrability and hyperbolic reduction are introduced, and their potential is gauged as a means of extending the range of application of geometric methods for solving hyperbolic partial differential equations. For directness, our work is expressed in local coordinates and formulated for semilinear hyperbolic systems in two independent variables. The theory is applied to the study of 1+1-wave maps into surfaces of revolution. It is shown that the differential system for any such wave map may be viewed as an integrable extension of a certain scalar, semilinear, hyperbolic partial differential equation which is explicitly constructed. Using this we discover a new integrable wave map system for which hyperbolic reduction leads to a large family of explicit wave maps.  相似文献   

12.
任意分配比的微波功率分配器   总被引:1,自引:0,他引:1  
圆波导中TE11模式波的电场在波导壁上随角度按正弦(或余弦)变化.如果在其侧壁上沿径向接两根互相垂直的波导,波导绕轴转动时两根波导中所分配的功率将随旋转角度而变化.这样就可以设计出任意分配比的微波功率分配器.通过HFSS的模拟计算完成了该功分器的设计,同时设计了一个新型的圆波导TE11模式转换器.  相似文献   

13.
The longitudinal-random-fieM mixed Ising model consisting of arbitrary spin values has been studied by the use of an effective field theory with correlations (EFT). The phase diagrams of systems with mixed spins: σ = 1/2, S = 1; σ = 1/2, S = 3/2 are plotted. Not only the discontinuity at T = 0 K, is found when both longitudinal fields are trimodal distributed, but also the trieritical behavior is observed in these phase diagrams between the bimodal and trimodal distributions of longitudinal fields, which is different from the single-spin one. The appearance of tricritical point is independent of the coordination number and spin values.  相似文献   

14.
Two sets of asymptotically hyperbolic initial data are defined, which correspond to the spatial infinity in asymptotically AdS spacetimes and to the null infinity in asymptotically Minkowski spacetimes respectively. The positive mass theorem involving the total energy, the total linear momentum and the total angular momentum is established for these initial data sets.Research partially supported by National Natural Science Foundation of China under grant 10231050 and the innovation project of the Chinese Academy of Sciences.  相似文献   

15.
We propose a hyperbolic function form of the Cardassian component in the Cardassian model. Using the repartition of this Cardassian component, we can obtain a non-zero gravitational interaction between the time derivative of Ricci scalar curvature and the baryon/lepton number current in the radiation-dominated universe.Furthermore, the other term that acts like a non-zero cosmological constant would give an accelerated expansion of current universe and the features of this model do not violate our desired requirements.  相似文献   

16.
We construct a number of explicit examples of hyperbolic monopoles, with various charges and often with some platonic symmetry. The fields are obtained from instanton data in ${\mathbb{R}^4}$ that are invariant under a circle action, and in most cases the monopole charge is equal to the instanton charge. A key ingredient is the identification of a new set of constraints on ADHM instanton data that are sufficient to ensure the circle invariance. Unlike for Euclidean monopoles, the formulae for the squared Higgs field magnitude in the examples we construct are rational functions of the coordinates. Using these formulae, we compute and illustrate the energy density of the monopoles. We also prove, for particular monopoles, that the number of zeros of the Higgs field is greater than the monopole charge, confirming numerical results established earlier for Euclidean monopoles. We also present some one-parameter families of monopoles analogous to known scattering events for Euclidean monopoles within the geodesic approximation.  相似文献   

17.
We study the twistor theory of singular hyperbolic SU(2) monopoles following the approach taken by Kronheimer [9] in the Euclidean case. We use our results to show that the moduli space of charge 1 monopoles possesses a natural 2-sphere of scalar flat Kähler metrics. In the zero mass limit, the metrics reduce to a class of metrics first studied by LeBrun in [10].  相似文献   

18.
Abstract

The generalization of parasupersymmetric quantum mechanics generated by an arbitrary number of parasupercharges and characterized by an arbitrary order of paraquantization is given. The relations for parasuperpotentials are obtained. It is shown that parasuperpotentials can be explicitly expressed via one arbitrary function.  相似文献   

19.
In this paper, we show that some special mixed quantum resource experience the same property of pure entanglement such as Bell state for quantum teleportation. It is shown that one mixed state and three bits of classical communication cost can be used to teleport one unknown qubit compared with two bits via pure resources. The schemes are easily implement with model physical techniques. Moreover, these resources are also optimal and typical for faithfully remotely prepare an arbitrary qubit, two-qubit and three-qubit states with mixed quantum resources. Our schemes are completed as same as those with pure quantum entanglement resources except only 1 bit additional classical communication cost required. The success probability is independent of the form of the mixed resources.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号