Showing papers on "Four-force published in 1974"
TL;DR: In this article, a logical introduction to superluminal reference frames is given, along with a group of generalized relativistic Lorentz transformations (GLT) elements.
Abstract: 210 1. Foreword. 211 2. Historical remarks. 212 3. Special relativity revisited: logical introduction to Superluminal reference frames. 212 3\"1. Postulates. 213 3\"2. Duali ty principle. 214 3\"3. Four-vector properties. 215 3\"4. Superluminal inertial frames. 215 3\"5, Generalized relativistic transformations. 217 3\"6. Four-momentum. 218 3\"7. Conservation laws. 218 4. Group G of g~'neralized Lorentz transformations (GLT). 218 4\"1. The group elements. 219 4\"2. Tensors. 220 4\"3. Transcendent transformations. 222 4\"4. GLT's matricial form. 223 4\"5. Physical meaning (if the four subsets of G. 227 4\"6. Par~meU'ization of the elements of G. 229 5. Generalized velocity composition law. 231 6. Geometrical interpretat ion of GLT's. Comparison of space and time intervals. 235 7. Ant imat ter and tachyons. A (~third postulate,): the Dirac-StiickelbergFeynmau-Sudarshan <~reinterpretation principle )) (RIP). 235 7\"1. Bradyons, luxons, tachyons. 236 7\"2. Four-momentum space. 238 7\"3. The ((reinterpretation principle)): the thi rd postulate.
214 citations
TL;DR: The initial value equations of general relativity are formulated as a system of four coupled quasilinear elliptic equations as discussed by the authors, which result from a covariant orthogonal decomposition of symmetric tensors and a generalized technique of conformal deformation.
Abstract: The initial-value equations of Einstein's theory of general relativity are formulated as a system of four coupled quasilinear elliptic equations. These equations result from a covariant orthogonal decomposition of symmetric tensors and a generalized technique of conformal deformation of initial data. Mathematical properties and global integrability conditions of the equations are discussed. Physical interpretation of the independent and dependent data is given for both spatially closed and asymptotically flat initial-data sets. In the latter case, the four dependent functions constitute long-range scalar and vector potentials which determine the total mass and total linear and angular momenta of an isolated system. The definitions of linear and angular momenta suggest a unique extension to asymptotically flat three-spaces of the group of translations and rotations of flat three-space. In turn, the "almost symmetries" thus defined lead to Gaussian theorems expressing the equality of certain surface and volume integrals for total linear and angular momenta. An interpretation of the scalar and vector potentials for closed three-spaces is also given. In the Appendix we treat the special case of conformally flat initial data.
157 citations
TL;DR: In this paper, an analysis of the active and passive interpretations of symmetry operations is offered, which yields an evaluation of the old covariance-invariance issue and also demonstrates that the passive interpretation, insofar as it is not trivial, is parasitic on the active picture.
Abstract: This paper represents an attempt to clarify a number of long-standing issues concerning the nature and status of the special and general principles of relativity in particular and symmetry or invariance principles in general. An analysis of the active and passive interpretations of symmetry operations is offered. This analysis yields an evaluation of the old covariance-invariance issue. It also demonstrates that the passive interpretation, insofar as it is not trivial, is parasitic on the active picture. Finally, the analysis shows that grave difficulties lie in the way of any attempt to generalize the special principle of relativity in a manner like the one Einstein originally proposed.
39 citations
35 citations
TL;DR: In this article, a Hamiltonian formalism for asymptotically flat spaces in general relativity which is manifestly covariant under Poincare transformations at infinity is proposed.
26 citations
TL;DR: In this paper, the general solution of Einstein's equations for a stationary cylindrically symmetric distribution of pressure-free matter is obtained. But it contains a function which may be freely prescribed.
Abstract: The general solution of Einstein's equations for a stationary cylindrically symmetric distribution of pressure-free matter is obtained. It contains a function which may be freely prescribed. Using this freedom examples are given of new types of singularity in General Relativity.
22 citations
21 citations
18 citations
TL;DR: The exterior solution for a radiating sphere in general relativity is known as mentioned in this paper, and the complete exterior solution when the radiating spheres is charged is presented in the paper "Exterior Solution for a Radial Sphere in General Relativity".
Abstract: The exterior solution for a radiating sphere in general relativity is known. The complete exterior solution when the radiating sphere is charged is presented.
15 citations
TL;DR: In this paper, a general treatment for relativistic statics is given in the framework of the asynchronous formulation of Cavalleri and Salgarelli, in which pivot events are introduced and the motion of the pivot point is treated in the same way as a particle.
Abstract: A general treatment for relativistic statics is given in the framework of the asynchronous formulation of Cavalleri and Salgarelli. In particular, pivot events are introduced and the motion of the pivot point is treated in the same way as the motion of a particle. The new definition allows the development of relativistic statics in a form similar to that of its classical counterpart.
15 citations
TL;DR: In this paper, it is shown that cosmological structures can be used to make tachyon-type theories that do not contain logical paradoxes, and a general-relativistic Proca equation is analyzed as an example of a field-theoretic model that can have this type of tachyonic behavior.
Abstract: It is shown that cosmological structures can be used to make tachyonic theories that do not contain logical paradoxes. A general-relativistic Proca equation is then analyzed as an example of a field-theoretic model that can have this type of tachyonic behavior. It is found that only one form of this equation never gives tachyon-type behavior.
TL;DR: Some similarities between P-P wave space-times and complex recurrent and conformally symmetric space times in general relativity are discussed in this article, where the similarities between the two types of wave spaces are discussed.
Abstract: Some similarities between 'P-P' wave space-times and complex recurrent and conformally symmetric space-times in general relativity are discussed.
TL;DR: In this paper, it was shown how General Relativity may be derived from a conformally invariant theory of gravitation in interaction with matter after recognising the existence of a family of canonical gauges.
TL;DR: In this article, the existence of superluminal reference-frames and faster-than-light objects can be inferred from the Extended Theory of Relativity, when its validity is not arbitrarily confined to sublinear velocities.
Abstract: From the Special Relativity Theory, the existence of Superluminal reference-frames and faster-than-light objects can be inferred, when its validity is not arbitrarily confined to subluminal velocities. The ‘Extended Theory of Relativity’ allows in particular extending the Doppler effect formulae to Superluminal sources. This point is here explored, due to its possible astrophysical interest. Some other questions are briefly considered, regarding the possibility of ‘radio contact’ between subluminal and Superluminal objects.
01 Jan 1974
Abstract: From the very special relativity theory, the existence of Superluminal reference frames and faster-than-light objects can be inferred, when its validity is not arbitrarily confined to subluminal velocities. Recently, in fact, special relativity has been extended to Superluminal inertial frames and to tachyons, thus allowing a self-consistent development of a «classical theory» of tachyons. In this paper, it is shown that the «extended theory of relativity» allows in particular extending the Doppler-effect formulae to Superluminal sources. The possibilities of radiocontact between subluminal and Superluminal objects are considered as well. The behaviour of tachyonic bodies in the gravitational field has been clarified. Tachyons are predicted to suffer a gravitationalrepulsion (so theymight be considered as the «antigravitational matter»);however, owing to their dynamics, they happen finally to bendtowards the gravitational source,as usual objects do (even if with different curvatures). At last the problem of gravitational Cerenkov radiation (GCR) is studied. Contrarily to the previous authors, extended relativity predicts tachyonsnot to emit GCR in vacuum or in bradyonic (subluminal) media.
TL;DR: In this paper, a criterion for stability of a charged sphere is obtained by use of two different methods, i.e., stability criterion for the stability of the charged sphere and stability of its dynamics.
Abstract: A criterion for stability of a charged sphere is obtained by use of two different methods. The result is applied to a charged dust in order to investigate its stability.
TL;DR: In this paper, general-relativistic analogues of some classical theorems and equations of magneto-hydrodynamics are found and their relevance to astrophysics is briefly discussed.
Abstract: General-relativistic analogues of some classical theorems and equations of magneto-hydrodynamics are found and their relevance to astrophysics is briefly discussed.
TL;DR: In this article, it was shown that none of the classical tests of general relativity can distinguish between Einstein's and Whitehead's theories of gravitation, and a feasible experimentum crucis was delineated.
TL;DR: In this article, the EIH Lagrangian is recovered by making a Lorentz transformation, followed by a canonical transformation and an appropriate symmetrization in the two masses.
Abstract: Starting from the metric in harmonic coordinates for a test particle m1 around a heavy particle m2(m2≫m1) at rest, the EIH Lagrangian is recovered by making a Lorentz transformation, followed by a canonical transformation and an appropriate symmetrization in the two masses. This raises the question of a special relativity content in general relativity, a feature not directly implied by the general covariance.
TL;DR: In this article, the Lorentz group is generalized to rotations in five dimensions, a ten-parameter group, and special and general Relativity are tentatively welded into one unified covariance scheme in five-dimensional space-time.
Abstract: Relativistic physics is described by a sixteen-component hypercomplex number system which reduces to the eight-component complex quaternion system when rest mass → 0. Rest mass is identified with a scale setting, cyclic, fifth dimension. The Lorentz group is generalized to rotations in five dimensions, a ten-parameter group. Special Relativity and General Relativity are tentatively welded into one unified covariance scheme in five-dimensional space-time.
TL;DR: In this article, the topological and geometrical restrictions on spatially integrable space-times foliated by space-like hypersurfaces are investigated, and the topology of the hypersurface is analyzed.
Abstract: The topological and geometrical restrictions on spatially integrable space-times foliated by space-like hypersurfaces are investigated.
TL;DR: In this article, it was shown that on this point, although the result found is correct (to first order), the equivalence principle was in error and the Doppler effect was incorrect.
Abstract: EVER since Einstein introduced the equivalence principle and used it, in conjunction with the Doppler effect, to derive the gravitational redshift of spectral lines1, this argument has been an ingredient of many2–6 (though not all7–11) expositions of relativity theory. We show here that on this point Einstein was in error, although the result found is correct (to first order).
TL;DR: In this article, the nonsymmetric motion of a perfect fluid in the framework of general relativity was studied, where all the thermodynamic processes are adiabatic and only mechanical energy may be released in the process.
TL;DR: In this paper, an outline of recent applications of modern infinitedimensional manifold techniques to general relativity is presented and the uses, scope, and future of such methods are delineated.
Abstract: An outline of recent applications of modern infinitedimensional manifold techniques to general relativity is presented. The uses, scope, and future of such methods are delineated. It is argued that the mixing of the two active fields of general relativity and global analysis provides stimulation for both fields as well as producing good theorems. The authors' work on linearization stability of the Einstein equations is sketched out to substantiate the arguments.