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Showing papers on "Special relativity (alternative formulations) published in 1997"


Book
29 Nov 1997
TL;DR: The foundations of special relativity relativistic kinematics, electrodynamics in media, and the test theories of the special relativity this article have been discussed in detail in this article.
Abstract: The foundations of special relativity relativistic kinematics the test theories of special relativity relativistic mechanics electrodynamics in media the proca vector field test of constancy of velocity of light tests of time dilation electromagnetism tests tests of relativistic mechanics upper bounds on photon mass tests of Thomas precession appendix - Minkowvski space-time, four dimension formulation.

133 citations


Journal ArticleDOI
TL;DR: In this paper, the well posedness of the evolution of the constraints in standard 3+1 general relativity is established by means of the Bianchi identities, which is relevant to the problem of unconstrained numerical evolution.
Abstract: The well posedness of the evolution of the constraints in standard 3+1 general relativity is established by means of the Bianchi identities. Other related nonstandard 3+1 cases which can be analyzed along similar lines are considered as well. The well posedness of the propagation of the constraints is relevant to the problem of unconstrained numerical evolution.

57 citations


Book
01 Jan 1997
TL;DR: In this paper, the authors presented a new special relativity theory for cosmology in which it was assumed that gravitation can be neglected and thus the bubble constant can be taken as a constant.
Abstract: Recently we presented a new special relativity theory for cosmology in which it was assumed that gravitation can be neglected and thus the bubble constant can be taken as a constant. The theory was presented in a six-dimensional hvperspace. three for the ordinary space and three for the velocities. In this paper we reduce our hyperspace to four dimensions by assuming that the three-dimensional space expands only radially, thus one is left with the three dimensions of ordinary space and one dimension of the radial velocity.

49 citations


Journal ArticleDOI
Masaru Shibata1
TL;DR: In this paper, the authors present a method to find the apparent horizon (AH) on a special family of 3D spacelike hypersurfaces which has a symmetry around the $z$ axis as well as the reflection one with respect to the equatorial plane.
Abstract: We present a method to find the apparent horizon (AH) on a special family of three-dimensional (3D) spacelike hypersurfaces which has $\ensuremath{\pi}$-rotation symmetry around the $z$ axis as well as the reflection one with respect to the equatorial plane. In a nonaxisymmetric 3D hypersurface, the AH, if it exists, is determined by solving a 2D elliptic-type equation. In the present method, we solve the elliptic-type equation as a boundary value problem. To test this method, we apply it to a variety of nonaxisymmetric 3D hypersurfaces which can be obtained by solving the constraint equations in general relativity. We find that the present method works well in all cases.

33 citations


Journal ArticleDOI
TL;DR: The existence of a definite tangent space structure (metric with Lorentzian signature) in the general theory of relativity is the consequence of a fundamental assumption concerning the local validity of special relativity as mentioned in this paper.
Abstract: The existence of a definite tangent space structure (metric with Lorentzian signature) in the general theory of relativity is the consequence of a fundamental assumption concerning the local validity of special relativity. There is then at the heart of Einstein's theory of gravity an absolute element which depends essentially on a common feature of all the non‐gravitational interactions in the world, and which has nothing to do with space‐time curvature. Tentative implications of this point for the significance of the vacuum solutions in general relativity, and for the issue of quantising gravity, are briefly examined.

26 citations


Journal ArticleDOI
TL;DR: In this paper, the Michelson-Morley experiment was used to verify the existence of high-energy cosmic rays, which places strong constraints on Lorentz non-invariance.
Abstract: Searches for anisotropies due to Earth's motion relative to a preferred frame -- modern versions of the Michelson-Morley experiment -- provide precise verifications of special relativity. We describe other tests, independent of this motion, that are or can become even more sensitive. The existence of high-energy cosmic rays places strong constraints on Lorentz non-invariance. Furthermore, if the maximum attainable speed of a particle depends on its identity, then neutrinos, even if massless, may exhibit flavor oscillations. Velocity differences far smaller than any previously probed can produce characteristic effects at accelerators and solar neutrino experiments.

24 citations


Journal ArticleDOI
TL;DR: In this article, the modified general relativity theory of Rastall, Al-Rawaf and Taha is discussed in both the radiation-and matter-dominated flat cosmological models.
Abstract: Aspects of the modified general relativity theory of Rastall, Al-Rawaf and Taha are discussed in both the radiation- and matter-dominated flat cosmological models. A nucleosynthesis constraint on the theory's free parameter is obtained and the implication for the age of the Universe is discussed. The consistency of the modified matter-dominated model with the neoclassical cosmological tests is demonstrated.

21 citations


Book
01 Jan 1997
TL;DR: The Big Bang, black holes, unified fields and unified fields have been studied extensively in Relativity and science fiction literature as mentioned in this paper, with a focus on the nature of light and time.
Abstract: Preface 1. A revolution in time 2. The nature of light 3. Light and time 4. The ultimate speed 5. E=mc2 6. Matter and anti-matter 7. Little boy and fat man: relativity in action 8. Down to Earth 9. Warped space 10. The Big Bang, black holes and unified fields Afterword: Relativity and science fiction Index.

20 citations


Journal ArticleDOI
TL;DR: In this paper, the authors reviewed old and recent ideas concerning the nature of time, starting from Mach's refusal of Newton's absolute time, and concluded that the slowing down of moving clocks is a real phenomenon.
Abstract: Old and recent ideas concerning the nature of time are reviewed, starting from Mach's refusal of Newton's absolute time. Many experiments show that the slowing down of moving clocks is a real phenomenon. Such must then also be the so-called “twin paradox,” which owes its name to its evident incompatibility with the philosophy of relativism (not to be confused with the theory of relativity). The Lorentz reformulation of special relativity started by postulating physical effects of the ether, but accepted Einstein's clock synchronization. Only because of this Lorentz could not understand the advantages of an easily deducible different theory. As stressed by Popper, one of the main problems of the usual approach is the introduction of a superdeterministic universe. Recent results obtained by the author show that a theory is possible, based on relative time but on absolute simultaneity, in which the conceptual difficulties of relativity are avoided.

19 citations


Journal ArticleDOI
TL;DR: In this paper, the relationship between the acceleration of the rocket twin and time dilation is clarified, and the authors give a variation of the twin paradox of special relativity in which the relationship of acceleration and time-dilation is explained.
Abstract: We give a variation of the twin paradox of special relativity in which the relationship of acceleration of the rocket twin and time dilation is clarified.

18 citations


Journal ArticleDOI
TL;DR: The empirical content of the modern definition of relativity given in the Andersonian approach to spacetime theory has been overestimated and it does not imply the empirical relativity Galileo illustrated in his famous ship thought experiment as mentioned in this paper.
Abstract: The empirical content of the modern definition of relativity given in the Andersonian approach to spacetime theory has been overestimated. It does not imply the empirical relativity Galileo illustrated in his famous ship thought experiment. I offer a number of arguments-some of which are in essential agreement with a recent analysis of Brown and Sypel [1995]-which make this plausible. Then I go on to present example spacetime theories which are modern relativistic but violate Galileo's relativity. I end by briefly discussing the prospects for improving on modern relativity.


Journal ArticleDOI
TL;DR: In this article, it is shown how to derive the three classic tests of general relativity from Newtonian gravity and special relativity in a form at least partly accessible to pre-university students.
Abstract: It is often assumed that the three classic tests of general relativity require the full mathematical apparatus of that theory for their derivation. In fact, it is possible to derive them from Newtonian gravity and special relativity in a form at least partly accessible to pre-university students.


Journal Article
TL;DR: In this article, a survey of recent results on solutions of the Einstein equations with matter is presented and a number of open questions are stated, and some remarks are made on the methods which have been used, and could be used in the future, to study solutions to the problem of general relativity with matter.
Abstract: Recent results on solutions of the Einstein equations with matter are surveyed and a number of open questions are stated. The first group of results presented concern asymptotically flat spacetimes, both stationary and dynamical. Then there is a discussion of solutions of the equations describing matter in special relativity and Newtonian gravitational theory and their relevance for general relativity. Next spatially compact solutions of the Einstein-matter equations are presented. Finally some remarks are made on the methods which have been used, and could be used in the future, to study solutions of the Einstein equations with matter.

Posted Content
TL;DR: In this paper, the authors introduce a critical distance scale, $a$, below 10E-25 cm (the wavelength scale of the highest-energy observed cosmic rays) allowing to consider models compatible with standard tests of special relativity, where a small violation of Lorentz symmetry (a$ can, for instance, be the Planck length, around 10 E-33 cm) produces dramatic effects on the interaction properties of very high-energy particles.
Abstract: Special relativity has been tested at low energy with great accuracy, but these results cannot be extrapolated to the very high-energy region. Introducing a critical distance scale, $a$ , below 10E-25 cm (the wavelength scale of the highest-energy observed cosmic rays) allows to consider models, compatible with standard tests of special relativity, where a small violation of Lorentz symmetry ($a$ can, for instance, be the Planck length, around 10E-33 cm) produces dramatic effects on the interaction properties of very high-energy particles. Lorentz symmetry violation may potentially solve all the basic problems raised by the highest-energy cosmic rays (origin and energy, propagation...). Furthermore, superluminal sectors of matter may exist and release very high-energy ordinary particles or directly produce very high-energy cosmic-ray events with unambiguous signatures in very large detectors. We discuss these phenomena, as well as the cosmic-ray energy range (well below the energy scale associated to the fundamental length) and experiments where they could be detected and studied.


Journal ArticleDOI
TL;DR: In this paper, the rotating disk as an example of a non-Euclidean space is carefully examined; the basic arguments of Einstein are emphasized; a new approach is also presented which resolves the Ehrenfest paradox.
Abstract: In this paper, the rotating disk as an example of a non-Euclidean space is carefully examined; the basic arguments of Einstein are emphasized. A new approach is also presented which resolves the Ehrenfest paradox.

Journal ArticleDOI
11 Jan 1997
TL;DR: In this paper, interviews about special relativity are realized with students of a Modem Physics course, and the results of the interviews' analysis suggest that conceptual change doesn't mean a substitution of classic physics conceptions by the relativistic ones but that there is an interactive coexistence of both.
Abstract: Interviews about special relativity are realized with students of a Modem Physics course. The results of the interviews’ analysis suggest that conceptual change doesn’t mean a substitution of classic physics conceptions by the relativistic ones but that there is an interactive coexistence of both.

Journal ArticleDOI
TL;DR: In this article, the mapping class groups of diffeomorphisms fixing a frame at a point for general classes of 3-manifolds were investigated, which form the equivalent to the groups of large gauge transformations in Yang-Mills theories.
Abstract: We investigate the mapping class groups of diffeomorphisms fixing a frame at a point for general classes of 3-manifolds. These groups form the equivalent to the groups of large gauge transformations in Yang-Mills theories. They are also isomorphic to the fundamental groups of the spaces of 3-metrics modulo diffeomorphisms, which are the analogues in General Relativity to gauge-orbit spaces in gauge theories.

Book ChapterDOI
01 Jan 1997
TL;DR: In this paper, it was shown that the old notions of Newtonian absolute time and Euclidian absolute space were contradictory with the impossibility of detection of the Earth's absolute motion, and therefore, they were discarded.
Abstract: Maxwell’s electromagnetism equations and the old notions of Newtonian absolute time and Euclidian absolute space were contradictory with the impossibility of detection of the Earth’s absolute motion.

Journal ArticleDOI
E. Comay1
TL;DR: In this paper, it was proved that the theory of the longitudinal magnetic field ascribed by Evans to a circularly polarized electromagnetic wave is inconsistent with special relativity, and it was further proved that this theory is not the case.
Abstract: The longitudinal magnetic field ascribed by Evans to a circularly polarized electromagnetic wave is discussed. It is proved that this theory is inconsistent with special relativity.


13 Nov 1997
TL;DR: In this article, the effects of Lorentz symmetry violation (LSV) on kinematics and dynamics, as well as the cosmic-ray energy range (well below the energy scale associated to the fundamental length) and experiments (on earth and from space) where they could be detected.
Abstract: Special relativity has been tested at low energy with great accuracy, but these results cannot be extrapolated to very high-energy phenomena: this new domain of physics may actually provide the key to the, yet unsettled, question of the ether and the absolute rest frame. Introducing a critical distance scale, a, below 10E-25 cm (the wavelength scale of the highest-energy observed cosmic rays) allows to consider models, compatible with standard tests of special relativity, where a small violation of Lorentz symmetry (a can, for instance, be the Planck length) leads to a deformed relativistic kinematics (DRK) producing dramatic effects on the properties of very high-energy cosmic rays. For instance, the Greisen-Zatsepin-Kuzmin (GZK) cutoff does no longer apply and particles which are unstable at low energy (neutron, some hadronic resonances like the Delta++, possibly several nuclei...) become stable at very high energy. In these models, an absolute local rest frame exists (the vacuum rest frame, VRF) and special relativity is a low-momentum limit. We discuss the possible effects of Lorentz symmetry violation (LSV) on kinematics and dynamics, as well as the cosmic-ray energy range (well below the energy scale associated to the fundamental length) and experiments (on earth and from space) where they could be detected.




Posted Content
TL;DR: Two geometrical well-posed hyperbolic formulations of general relativity are described in this paper, and one admits any time-slicing which preserves a generalized harmonic condition.
Abstract: Two geometrical well-posed hyperbolic formulations of general relativity are described. One admits any time-slicing which preserves a generalized harmonic condition. The other admits arbitrary time-slicings. Both systems have only the physical characteristic speeds of zero and the speed of light.