## Citations with the tag: EINSTEIN field equations

### Results 101 - 150

- Symmetries of Einsteinï¿½s field equations with a perfect fluid source as examples of Lieï¿½Bï¿½cklund symmetries.

Stephani, H. // Journal of Mathematical Physics; Jul88, Vol. 29 Issue 7, p1650The framework of Lieï¿½Bï¿½cklund (or generalized) symmetries is used to give a unifying view of some of the known symmetries of Einsteinï¿½s field equations for the vacuum or perfect fluid case (with a ï¿½=p or a ï¿½+3p=0 equation of state). These symmetries occur if space-time...

- Shear-free normal cosmological models.

Krasinski, Andrzej // Journal of Mathematical Physics; Feb89, Vol. 30 Issue 2, p433Shear-free normal cosmological models are the perfect fluid solutions of Einsteinï¿½s equations in which rotation and shear vanish, and which are not static [they were all found by A. Barnes, Gen. Relativ. Gravit. 4, 105 (1973)]. They are either spherically, plane, or hyperbolically...

- Symmetries of the self-dual Einstein equations. I. The infinite-dimensional symmetry group and its low-dimensional subgroups.

Boyer, C. P.; Winternitz, P. // Journal of Mathematical Physics; May89, Vol. 30 Issue 5, p1081This is the first of two papers in which the authors give a complete classification of symmetry reduced solutions of Plebanskiï¿½s potential equation for self-dual Einstein spaces. In this first part the infinite pseudogroup of symmetries of Plebanskiï¿½s equation is described, and the...

- The gravitational field of a spinning pencil of light.

Mitskievic, Nikolai Vsevolodovich; Kumaradtya, Krishnadeva K. // Journal of Mathematical Physics; May89, Vol. 30 Issue 5, p1095An exact solution of Einsteinï¿½s equations in a vacuum (outside of singularities), belonging to Kundtï¿½s class and Petrov type N, is interpreted as the metric of a spinning pencil of light (a linear source infinitely extended in one direction and moving with the speed of light). It is...

- The uniqueness of the Bekenstein black hole.

Xanthopoulos, Basilis C.; Zannias, Thomas // Journal of Mathematical Physics; Jul91, Vol. 32 Issue 7, p1875The general static, spherically symmetric, asymptotically flat solution of the Einstein equations coupled to a conformal scalar field is determined; it depends on three free parameters. One of the parameters is eliminated by the requirement that the solution admits a smooth horizon and no naked...

- Nondiagonal double seed solutions and double soliton solution family of the Einstein equations.

Gao, Ya-Jun; Zhong, Zai-Zhe // Journal of Mathematical Physics; Jan1992, Vol. 33 Issue 1, p278By using the double inverse scattering method, the problem of how to find new soliton solutions of the stationary axisymmetric vacuum field equation is studied. It is found that, for some kinds of seed solutions, the scattering wave functions can be directly obtained. Some examples of...

- Einstein gravity coupled to a massless conformal scalar field in arbitrary space-time dimensions.

Xanthopoulos, Basilis C.; Dialynas, Thanassis E. // Journal of Mathematical Physics; Apr92, Vol. 33 Issue 4, p1463For space-times of arbitrary dimensionality two transformations are obtained that applied to any solution of the Einstein equations coupled to a minimally coupled scalar field construct a solution of the Einstein equations coupled to a conformal scalar field. The transformations are conformal...

- Relationship between the Spectral Densities of Einstein Coefficients for Absorption and Stimulated Emission: Physical Consequences.

Shalagin, A. M. // JETP Letters; 3/25/2002, Vol. 75 Issue 6, p253The spectral densities of Einstein coefficients for absorption and stimulated emission in a two-level quantum system are not equal to each other beyond the absorption (emission) line if the homogeneous broadening caused by interaction with a thermostat is much larger than the natural width. In...

- The Riemannï¿½Hilbert transformation for an approach to a representation of the Virasoro group.

Li, Wei; Hou, Bo-yu // Journal of Mathematical Physics; Jun89, Vol. 30 Issue 6, p1198In this paper, it is the intent to apply the Riemannï¿½Hilbert transformation developed by Hauser and Ernst [J. Math. Phys. 21, 1126, 1418 (1980)] in providing a new representation of the Virasoro group. It is found that the Geroch group that acts on the solution space of the Einstein field...

- A spherical collapse solution with neutrino outflow.

Glass, E. N. // Journal of Mathematical Physics; Aug90, Vol. 31 Issue 8, p1974A three-parameter family of solutions of Einsteinï¿½s field equations is given that represents a collapsing perfect fluid with outgoing neutrino flux. Solutions with ï¿½ï¿½nakedï¿½ï¿½ singularities are exhibited. They can be forbidden by requiring pressure less than or equal to...

- Stationary Bianchi type II perfect fluid models.

Nilsson, Ulf S.; Uggla, Claes // Journal of Mathematical Physics; May97, Vol. 38 Issue 5, p2611Studies Einstein's field equations for stationary Bianchi type II models with perfect fluid source. Rewriting of the field equations as a system of autonomous first-order differential equations; Dimensionless variables introduced for which the reduced phase space is compact.

- Form invariance of differential equations in general relativity.

Chimento, Luis P. // Journal of Mathematical Physics; May97, Vol. 38 Issue 5, p2565Studies the reduction of Einstein equations for several matter sources in Robertson-Walker and Bianchi I type metrics to a kind of second-order nonlinear ordinary differential equation. Generalized statistical mechanics for values; Linearization of the equation; Application of form invariance...

- Rotating dust solutions of Einstein's equations with 3-dimensional symmetry groups. II. One....

Krasinski, Andrzej // Journal of Mathematical Physics; Jan1998, Vol. 39 Issue 1, p401Part II. Investigates the rotating dust solutions of Einstein's equation that posses 3-dimensional symmetry groups. Extension of one Killing fields on the fields of velocity and rotation; Independence of the vectors on the velocity and rotation; Identification of classes of solutions in the...

- Similarity reduction for a class algebraically special perfect fluids.

Rainer, A.; Stephani, H. // Journal of Mathematical Physics; Feb99, Vol. 40 Issue 2, p897Performs a complete symmetry analysis of the field equations for a class of perfect fluids. Use of the results for a symmetry reduction of the field equations and the construction of similarity solutions; Description of the reduced field equations.

- Static stringlike solutions in five-dimensional relativity. II.

Gravel, Pierre // Journal of Mathematical Physics; May2000, Vol. 41 Issue 5In this paper we find five-dimensional static strings solutions to Einstein's equations in the context of the induced-matter approach to higher dimensional relativity. This is done by separating Einstein's equations for a metric depending on a radius and the extra coordinate. Extending previous...

- A Noncommutative Generalization of the Free-Field Yangï¿½Mills Equations.

McCabe, Gordon // International Journal of Theoretical Physics; Feb2006, Vol. 45 Issue 2, p350The purpose of this paper is to propose a noncommutative generalization of a gauge connection and the free-field Yangï¿½Mills equations. The paper draws upon the techniques proposed by Heller et al. for the noncommutative generalization of the Einstein field equations.

- Reduction of the Einstein equations in 2+1 dimensions to a Hamiltonian system over Teichmï¿½ller space.

Moncrief, Vincent // Journal of Mathematical Physics; Dec89, Vol. 30 Issue 12, p2907In this paper the ADM (Arnowitt, Deser, and Misner) reduction of Einsteinï¿½s equations for three-dimensional ï¿½ï¿½space-timesï¿½ï¿½ defined on manifolds of the form Sï¿½R, where S is a compact orientable surface, is discussed. When the genus g of S is greater than unity it is...

- Null geodesics in the gravitational field of a rotating, radiating body.

Hadley, R. H.; Mallett, R. L. // Journal of Mathematical Physics; Mar1993, Vol. 34 Issue 3, p1007A solution of the Einstein field equations for a rotating radiating body was presented by Carmeli and Kaye in 1977 [Ann. Phys. 103, 97 (1977)]. Their paper presented a new line element along with the corresponding energy-momentum tensor for the radiation field. The Newmanï¿½Penrose formalism...

- On a class of invariant coframe operators with application to gravity.

Itin, Yakov; Kaniel, Shmuel // Journal of Mathematical Physics; Sep2000, Vol. 41 Issue 9Let a differential 4D-manifold with a smooth coframe field be given. Consider the operators on it that are linear in the second order derivatives and quadratic in the first order derivatives of the coframe, both with coefficients that depend on the coframe variables. The article exhibits the...

- A black-box self-consistent field convergence algorithm: One step closer.

Kudin, Konstantin N.; Scuseria, Gustavo E.; Cance`s, Eric // Journal of Chemical Physics; 5/15/2002, Vol. 116 Issue 19, p8255A direct inversion iterative subspace version of the relaxed constrained algorithm is found to be a very powerful convergence acceleration technique for the solution of the self-consistent field equations found in the Hartree-Fock method and Kohn-Sham-based density functional theory (KS-DFT)....

- Wavelike solutions to the Einstein equations coupled to neutrino and gauge fields.

Torres del Castillo, G. F. // Journal of Mathematical Physics; Nov86, Vol. 27 Issue 11, p2756Starting from the plane-wave metric, solutions to the Einstein field equations coupled to a Weyl neutrino field and to a Yangï¿½Mills field are found. These solutions can be superposed to yield a solution with both sources if the direct interaction between them is neglected. A solution to the...

- Spherically symmetric solutions in higher dimensions.

Krori, K. D.; Borgohain, P.; Das, Kanika // Journal of Mathematical Physics; Oct89, Vol. 30 Issue 10, p2315An exact general solution of Einsteinï¿½s equations for spherically symmetric distribution of a perfect fluid in N dimensions is presented from which the whole class of spherically symmetric solutions may be obtained. As examples, some particular solutions obtainable from a general solution...

- The gravitational field of a charged, magnetized, accelerating, and rotating mass.

Garc�a D�az, Alberto; Bret�n Baez, Nora // Journal of Mathematical Physics; Mar1985, Vol. 26 Issue 3, p465The explicit expression of a Petrov type G solution to the Einsteinï¿½Maxwell equations is given. This new solution is endowed with eight arbitrary parameters; mass, Newmanï¿½Untiï¿½Tamburino (NUT) parameter, angular momentum, acceleration, electric and magnetic charges, and electric...

- Effects of the shear viscosity on the character of cosmological evolution.

Huang, Wung-Hong // Journal of Mathematical Physics; Mar1990, Vol. 31 Issue 3, p659Bianchi type I cosmological models are studied that contain a stiff fluid with a shear viscosity that is a power function of the energy density, such as ?=aen. These models are analyzed by describing the cosmological evolutions as the trajectories in the phase plane of Hubble functions. The...

- Exact model for a relativistic star.

Tikekar, Ramesh // Journal of Mathematical Physics; Oct90, Vol. 31 Issue 10, p2454Assuming that the physical three-space in a relativistic superdense star has the geometry of a three-spheroid, a static spherically symmetric model based on an analytic closed-form solution of Einsteinï¿½s field equations is presented. Assuming the density of the order of 2ï¿½1014 g cm-3,...

- Shear-free perfect fluids in general relativity II. Aligned, Petrov type III space-times.

Carminati, J. // Journal of Mathematical Physics; Oct90, Vol. 31 Issue 10, p2434Petrov type III, shear-free, perfect fluid solutions of the Einstein field equations, with a barotropic equation of state p=p(w) satisfying w+p[not_identically_equal_to_(3_lines_with_slashthrough)]0, are investigated. It is shown that if the acceleration of the fluid is orthogonal to the...

- Kaluzaï¿½Klein equations, Einsteinï¿½s equations, and an effective energy-momentum tensor.

Wesson, Paul S.; Ponce de Leon, J. // Journal of Mathematical Physics; Nov92, Vol. 33 Issue 11, p3883Following earlier work, it is inquired how far the 5-D Kaluzaï¿½Klein equations without sources may be reduced to the Einstein equations with sources. It is shown by algebraic means that this can be done, provided the extra part of the 5-D geometry is used appropriately to define an effective...

- Scalar field inhomogeneous cosmologies.

Feinstein, A.; Ibanez, J.; Labraga, P. // Journal of Mathematical Physics; Sep95, Vol. 36 Issue 9, p4962Describes exact solutions for the Einstein field equations corresponding to inhomogeneous cosmologies with an exponential-potential scalar field. Discussion the properties related to generalized inflation and asymptotic behavior of the models.

- Static Bondi energy in the teleparallel equivalent of general relativity.

Maluf, J.W.; da Rocha-Neto, J.F. // Journal of Mathematical Physics; Mar1999, Vol. 40 Issue 3, p1490Focuses on Bondi's radiating metric in the context of the teleparallel equivalent of general relativity (TEGR). Description of the asymptotic form of a radiating solution of Einstein's equations; Expression of Bondi's solution in asymptotically spherical three plus one coordinates; Lagrangian...

- Analysis of the cosmological Oppenheimer-Volkoff equations.

Winter, Dale // Journal of Mathematical Physics; Aug2000, Vol. 41 Issue 8Formulates the Oppenheimer-Volkoff equations with a nonzero cosmological constant. Analysis of the behavior of solutions; Derivation of the Oppenheimer-Volkoff equations from Einstein field equations; Applications of the equations; Model for the gravitational collapse of stars.

- Null surfaces formulation in three dimensions.

Forni, Diego M.; Iriondo, Mirta; Kozameh, Carlos N. // Journal of Mathematical Physics; Aug2000, Vol. 41 Issue 8The null surface formulation of general relativity is developed for 2+1 dimensional gravity. The geometrical meaning of the metricity condition is analyzed and two approaches to the derivation of the field equations are presented. One method makes explicit use of the conformal factor while the...

- On solution spaces of massless field equations with arbitrary spin.

Heidenreich, W. // Journal of Mathematical Physics; Aug86, Vol. 27 Issue 8, p2154The solution spaces of massless field equations [Laplacian_variant] ?=0, with ? being a tensor, a (multi)spinor, or a Raritaï¿½Schwinger field, are studied. They carry indecomposable representations of the Poincarï¿½ group whose invariant subspaces are determined. There exist indefinite...

- Total energy momentum in general relativity.

� Murchadha, Niall // Journal of Mathematical Physics; Aug86, Vol. 27 Issue 8, p2111The energy momentum of any asymptotically flat vacuum solution to the Einstein equations is a well-defined, conserved, Lorentz-covariant, timelike, future-pointing vector. The only requirement is that one be given asymptotically flat initial data that satisfy very weak continuity and falloff...

- Dual mass, H-spaces, self-dual gauge connections, and nonlinear gravitons with topological origin.

Magnon, Anne // Journal of Mathematical Physics; Aug86, Vol. 27 Issue 8, p2105An analogy between source-free, asymptotically Taubï¿½NUT magnetic monopole solutions to Einsteinï¿½s equation and self-(anti-self-) dual gauge connections is displayed, which finds its origin in the first Chern class of these space-times. A definition of asymptotic graviton modes is...

- Conformal transformations and viscous fluids in general relativity.

Carot, J.; Mas, Ll. // Journal of Mathematical Physics; Sep86, Vol. 27 Issue 9, p2336It is shown that viscous fluid solutions can be obtained by performing conformal transformations of vacuum solutions of Einsteinï¿½s field equations. The solutions obtained by such a procedure can be matched, under certain conditions, to their respective original vacuum metrics.

- Einsteinï¿½Maxwell equations and the conformal Ricci collineations.

Faridi, Abbas M. // Journal of Mathematical Physics; Jun87, Vol. 28 Issue 6, p1370The Einsteinï¿½Maxwell field equations for non-null electromagnetic fields are studied under the assumption of admitting a conformal Ricci collineation. It is shown that a non-null electromagnetic field does not admit any conformal Ricci collineation, unless the generators of the symmetry...

- Involutive systems of differential equations: Einsteinï¿½s strength versus Cartanï¿½s degrï¿½ dï¿½arbitraire.

Su�, Michael // Journal of Mathematical Physics; Feb91, Vol. 32 Issue 2, p392Three new theorems relating Einsteinï¿½s notions of ï¿½ï¿½strengthï¿½ï¿½ and ï¿½ï¿½compatibilityï¿½ï¿½ to the field of the initial-value problem are presented. These theorems result (i) in a first proof of Matthewsï¿½ conjectures concerning this relation for a wider...

- Stationary axisymmetric interior metric for a charged perfect fluid source.

Garc�a D., Alberto // Journal of Mathematical Physics; Mar1991, Vol. 32 Issue 3, p708A stationary axisymmetric type-D solution of the Einstein equations coupled with an electromagnetic field and a rigidly rotating perfect fluid distribution of finite dimensions is presented. For vanishing fluid parameters, it reduces to the Carter [A] metric, which contains among others the...

- Cosmological models that describe particle creation in the early universe and evolve into the ï¿½ï¿½present-dayï¿½ï¿½ universe.

Ponce de Leon, J. // Journal of Mathematical Physics; Dec91, Vol. 32 Issue 12, p3546The disappearance of the cosmological constant can be formally treated by means of similarity solutions of general relativity that evolve from a stage with conformal symmetry to a stage with homothetic symmetry. In this work it is assumed that in this transition the universe does not...

- The interaction of outgoing and ingoing spherically symmetric null fluids.

Holvorcem, Paulo R.; Letelier, Patricio S.; Anzhong Wang // Journal of Mathematical Physics; Jul95, Vol. 36 Issue 7, p3663Examines the reduction of the Einstein field equations coupled to two oppositely directed null fluids for spherically symmetric space-time to an autonomous system of three ordinary differential equations using similarity methods. Backscattering of an initially outgoing null fluid shell in a...

- Tomimatsu-Sato electrovacuum cosmic string solutions for delta=2 interacting with gravitational...

Papadopoulos, Demetrios B.; Xanthopoulos, Basilis C. // Journal of Mathematical Physics; Aug95, Vol. 36 Issue 8, p4248Presents a cylindrically symmetric solution for Einstein-Maxwell electro-vacuum equations. Provision of the mechanism for galaxy formation and gravitational focusing; Control of the degrees of freedom of the gravitational field (GF); Representation of relative strength of the electromagnetism...

- Exact solutions of the Einstein equations with sources from linearized solutions.

del Castillo, G.F. Torres // Journal of Mathematical Physics; Sep96, Vol. 37 Issue 9, p4584Discusses the exact solutions of the Einstein-Maxwell equations with sources from linearized solutions. Generalization of the Xanthopoulos theorem; Analogous solutions of the Einstein-Weyl equations.

- Linearization stability of the Einstein equation for Robertson-Walker models. I.

Bruna, Lluis; Girbau, Joan // Journal of Mathematical Physics; Oct99, Vol. 40 Issue 10, p5117Studies the linearization stability of the Einstein equation in the presence of matter. Robertson-Walker model considered; Stability of the equation in the case of the spacelike hypersurface having a constant curvature; Origin of the linearization stability of empty space Einstein equation.

- Linearization stability of the Einstein equation for Robertson-Walker models. II.

Bruna, Lluis; Girbau, Joan // Journal of Mathematical Physics; Oct99, Vol. 40 Issue 10, p5131Studies the linearization stability of the Einstein equation for Robertson-Walker models of curvature. Instability of the Einstein equation at the initial metric when the curvature is positive; Notation used in the study; Expressions needed in the proof of the theorem.

- Well-posed forms of the 3+1 conformally-decomposed Einstein equations.

Frittelli, Simonetta; Reula, Oscar A. // Journal of Mathematical Physics; Oct99, Vol. 40 Issue 10, p5143Shows that well-posed, conformally-decomposed formulations of the 3+1 Einstein equations can be obtained by densitizing the lapse and by combining the constraints with the evolution equations. Computation of the characteristics structure; Constraint propagation of the well-posed formulations;...

- Local twistors and the conformal field equations.

Frauendiener, Jo�rg; Sparling, George A. J. // Journal of Mathematical Physics; Jan2000, Vol. 41 Issue 1In this paper we establish the connection between Friedrich's conformal field equations and the conformally invariant formalism of local twistors. ï¿½ 2000 American Institute of Physics.

- General solutions of Einsteinï¿½s spherically symmetric gravitational equations with junction conditions.

Das, A.; DeBenedictis, A.; Tariq, N. // Journal of Mathematical Physics; Dec2003, Vol. 44 Issue 12, p5637Einsteinï¿½s spherically symmetric interior gravitational equations are investigated. Following Syngeï¿½s procedure, the most general solution of the equations is furnished in case T[sub 1][sup 1] and T[sub 4][sup 4] are prescribed. The existence of a total mass function, M(r,t), is...

- Waves in solids with vectorial microstructure.

Pastrone, Franco // Proceedings of the Estonian Academy of Sciences, Physics, Mathem; Mar2003, Vol. 52 Issue 1, p21A general model of solids with vectorial microstructures is introduced. Field equations are obtained via a variational principle, with natural boundary conditions. It is proved that scalar unidimensional bodies and Cosserat solids are included in this model. Waves and stability problems are...

- Gravoelectric dual of the Kerr solution.

Dadhich, Naresh; Patel, L. K.; Patel, L.K. // Journal of Mathematical Physics; Feb2000, Vol. 41 Issue 2By decomposing the Riemann curvature into electric and magnetic parts, we define the gravoelectric duality transformation by interchange of active and passive electric parts which amounts to interchange of the Ricci and Einstein tensors. It turns out that the vacuum equation is duality...

- On the linearization stability of the conformally (anti-) self-dual Einstein equations.

Torre, C. G. // Journal of Mathematical Physics; Dec90, Vol. 31 Issue 12, p2983The Einstein equations with a cosmological constant, when restricted to Euclidean space-times with anti-self-dual Weyl tensor, can be replaced by a quadratic condition on the curvature of an SU(2) (spin) connection. As has been shown elsewhere, when the cosmological constant is positive and the...