共查询到20条相似文献,搜索用时 10 毫秒
1.
It is shown that theC-metric (with parameters chosen to lie in suitable intervals) admits a conformal completion such that the space of generators of null infinity, , is a 2-sphere. This structure of is both necessary and sufficient for the analysis of gravitational radiation in exact general relativity. Bondi news (as well as the electromagnetic radiation field, in the charget case) is examined and found to be non-zero. Thus the issue of existence of exact solutions to the Einstein (and Einstein-Maxwell) equations admitting radiation (in the sense of Bondi, Sachs, and Penrose) is resolved. In addition, the analysis clarifies the sense in which the vacuumC-metric represents the gravitational field of two accelerating black-holes. 相似文献
2.
The known prepotential solutions F to the Witten-Dijkgraaf-Verlinde-Verlinde (WDVV) equation are parametrized by a set {α} of covectors. This set may be taken to be indecomposable, since . We couple mutually orthogonal covector sets by adding so-called radial terms to the standard form of F. The resulting reducible covector set yields a new type of irreducible solution to the WDVV equation. 相似文献
3.
H. Stephani 《General Relativity and Gravitation》1982,14(7):703-705
Metrics of the formds
2=dx
2+dy
2–dt
2+N
2
dz
2 are considered and found to contain rotating dust solutions as well as pure radiation fields. 相似文献
4.
5.
D. Eardley J. Isenberg J. Marsden V. Moncrief 《Communications in Mathematical Physics》1986,106(1):137-158
We present several results about the nonexistence of solutions of Einstein's equations with homothetic or conformal symmetry. We show that the only spatially compact, globally hyperbolic spacetimes admitting a hypersurface of constant mean extrinsic curvature, and also admitting an infinitesimal proper homothetic symmetry, are everywhere locally flat; this assumes that the matter fields either obey certain energy conditions, or are the Yang-Mills or massless Klein-Gordon fields. We find that the only vacuum solutions admitting an infinitesimal proper conformal symmetry are everywhere locally flat spacetimes and certain plane wave solutions. We show that if the dominant energy condition is assumed, then Minkowski spacetime is the only asymptotically flat solution which has an infinitesimal conformal symmetry that is asymptotic to a dilation. In other words, with the exceptions cited, homothetic or conformal Killing fields are in fact Killing in spatially compact or asymptotically flat spactimes. In the conformal procedure for solving the initial value problem, we show that data with infinitesimal conformal symmetry evolves to a spacetime with full isometry. 相似文献
6.
Some new exact solutions to the Burgers--Fisher equation and generalized Burgers--Fisher equation 下载免费PDF全文
Some new exact solutions of the Burgers--Fisher equation and
generalized Burgers--Fisher equation have been obtained by using the
first integral method. These solutions include exponential function
solutions, singular solitary wave solutions and some more complex
solutions whose figures are given in the article. The result shows
that the first integral method is one of the most effective
approaches to obtain the solutions of the nonlinear partial
differential equations. 相似文献
7.
8.
W. B. Bonnor 《General Relativity and Gravitation》1982,14(10):807-821
This is a review, covering known globally regular solutions describing either vacuum or fields with physically reasonable sources. The largest class is that with static spherical symmetry, but many others are known, even with A = 0. If A 0 there is a variety of regular cosmological solutions. 相似文献
9.
Edwin Ihrig 《General Relativity and Gravitation》1979,10(11):903-910
A symmetry principle is proposed which in the case whenT
ij
enjoys sufficient symmetry helps to pick out the physically relevant solution to Einstein's equations. 相似文献
10.
11.
A. N. Temchin 《Russian Physics Journal》1981,24(10):931-935
The quantities that determine the jump conditions for discontinuities in the second derivatives of the components of the metric tensor are obtained.Translated from Izvestiya Vysshykh Uchebnykh Zavedenii, Fizika, No. 10, pp. 40–43, October,1981.I take this opportunity to express my deep gratitude to L. R. Volevich for his constant attention to my work. 相似文献
12.
W. B. Bonnor 《Communications in Mathematical Physics》1976,51(3):191-199
The quasi-spherical collapsing space-time of Szekeres is investigated. The arbitrary functions can be chosen so that it has positive density, and no Killing vectors; yet a ballr<r
0 of it can joined to the Schwarzschild metric, and is therefore non-radiative. 相似文献
13.
A new quantum double is established from a new Hopf algebra and a new kind of quantum R-matrix is obtained. 相似文献
14.
Volker Perlick 《General Relativity and Gravitation》1991,23(12):1337-1348
We consider a special class of stationary rotating charged dust solutions of Einstein's field equations without cosmological constant. In these space-times, the motion of freely falling particles and of light rays can be visualized by the motion of charged particles in an appropriate model magnetic field. Any curl-free magnetostatic field, given on an open subset of Euclidean 3-space, can serve as a model magnetic field for a charged dust solution in this sense. The simplest example, corresponding to a homogeneous model magnetic field, is given by Som-Raychaudhuri space-time. Some other examples are worked out. 相似文献
15.
In the first part of this paper we describe a formalism capable of finding all homogeneous solutions of Einstein's field equations with any arbitrary energy-impulse tensor. In the second part we find all homogeneous vacuum solutions. 相似文献
16.
A. A. Coley 《International Journal of Theoretical Physics》1995,34(2):293-299
Some general solutions of the (general)D-dimensional vacuum Einstein field equations are obtained. The four-dimensional properties of matter are studied by investigating whether the higher-dimensional vacuum field equations reduce (formally) to Einstein's four-dimensional theory with matter. It is found that the solutions obtained give rise to an induced four-dimensional cosmological perfect fluid with a (physically reasonable) linear equation of state. 相似文献
17.
D. R. Matravers 《General Relativity and Gravitation》1976,7(12):937-947
Exact solutions to Einstein's field equations, which give rise to a Stäckel-separable Hamilton-Jacobi equation of the form $$,y,z)\left[ {X(x)\left( {\frac{{\partial S}}{{\partial x}}} \right)^2 - 2\left( {\frac{{\partial S}}{{\partial x}}} \right)\left( {\frac{{\partial S}}{{\partial t}}} \right) - 2\left( {\frac{{\partial S}}{{\partial y}}} \right)\left( {\frac{{\partial S}}{{\partial t}}} \right) + Z(z)\left( {\frac{{\partial S}}{{\partial z}}} \right)^2 - 2\left( {\frac{{\partial S}}{{\partial z}}} \right)\left( {\frac{{\partial S}}{{\partial t}}} \right) - F(x,y,z)\left( {\frac{{\partial S}}{{\partial t}}} \right)^2 } \right] = \lambda $$ are considered. It is shown that there are no solutions for whichD is a function ofx orz, orx andz. The exact solutions are of Petrov typeN and are plane polarized waves without rotation. Some of the solutions are given explicitly, up to two arbitary functions. For these solutions the Hamilton-Jacobi equation is reduced to an uncoupled set of first-order ordinary differential equations. 相似文献
18.
Lars Andersson Piotr T. Chruściel Helmut Friedrich 《Communications in Mathematical Physics》1992,149(3):587-612
The regularity of the solutions to the Yamabe Problem is considered in the case of conformally compact manifolds and negative scalar curvature. The existence of smooth hyperboloidal initial data for Einstein's field equations is demonstrated.Supported in part by NFR, the Swedish Academy of Sciences and the Gustavsson Foundation 相似文献
19.
A new method of new exact solutions and solitary wave-like solutions for the generalized variable coefficients Kadomtsev——Petviashvili equation 总被引:1,自引:0,他引:1 下载免费PDF全文
Using the solution of general Korteweg--de Vries (KdV) equation, the solutions of
the generalized variable coefficient Kadomtsev--Petviashvili (KP) equation are
constructed, and then its new solitary wave-like solution and Jacobi elliptic
function solution are obtained. 相似文献