Showing papers on "Special relativity (alternative formulations) published in 1995"

Eliminative Induction as a Method of Discovery: How Einstein Discovered General Relativity

Abstract: So began Einstein’s weary and consoling response of August 1915 to his correspondent Paul Hertz on a yet another proposal concerning the troubled and still incomplete general theory of relativity. Einstein had been working on the theory for eight years and within a few months would overcome his final obstacles, bringing to completion his greatest scientific achievement.’ My concern in this paper is to establish two theses about Einstein’s discovery of his general theory of relativity. The first concerns the heuristic methods he used to navigate the “chaos of possibilities”; the second concerns an important moral Einstein, the “mathematical ignoramus,” drew from the experience:

Did Einstein Stumble? The Debate Over General Covariance

Abstract: The objection that Einstein's principle of general covariance is not a relativity principle and has no physical content is reviewed. The principal escapes offered for Einstein's viewpoint are evaluated.

Mass and energy in General Relativity

Abstract: We consider the Denisov-Solov'ov example which shows that the inertial mass is not well defined in General Relativity. It is shown that the mathematical reason why this is true is a wrong application of the Stokes theorem. Then we discuss the role of the order of asymptotically flatness in the definition of the mass. In conclusion some comments on conservation laws in General Relativity are presented.

Emil Cohn’s electrodynamics of moving bodies

Abstract: A now forgotten figure, Emil Cohn was one of the leading experts in electrodynamics at the turn of the century. Unsatisfied with Lorentz’s electron theory, he proposed an alternative electrodynamics of moving bodies based on a modification of Maxwell’s macroscopic field equations that managed to account for all relevant electrodynamic and optical experiments, including that of Michelson and Morley. Some of his insights foreshadow aspects of Einstein’s relativity theory, especially the elimination of the ether and the criticism of Lorentz’s implicit distinction between true and measured coordinates of space and time. However, Cohn did not believe in the general validity of the relativity principle, and did not require a revision of the usual concepts of space and time.

The principle of relativity as applied to motional electromagnetic induction

Abstract: We describe the behavior of a unipolar generator that is an obvious variant of the Faraday disk. The behavior of our device, if properly interpreted, is in agreement with the principle of relativity. ‘‘For nearly a century after its discovery by Faraday in 1832 the unipolar generator was a conundrum for the theory of electromagnetism.’’—D. F. Bartlett et al. Phys. Rev. D 16(12), 3459–3463 (1977).

A symplectic interpretation of some wave fronts in general relativity

Abstract: In order to study the symplectic structures of the elementary relativistic free particles in general relativity, a nonvectorial associated fiber bundle is constructed over the space‐time manifold. A foliation in the space‐time is achieved which gives rise to the geodesics principle for massive particles and wave fronts for massless particles.

A note on the strengths of singularities in the Einstein-Cartan theory

Abstract: In general relativity bounds were given on the possible divergency rates of the elements and of the trace of the tidal-force tensorR abcdubud along incomplete maximal causal geodesics. These results are transformed into the Einstein-Cartan theory and are illustrated with two simple examples of spacetimes filled with charged spinless and spinning perfect fluids interacting with electromagnetic field.

Boundary terms in complex general relativity

Abstract: A recent analysis of real general relativity based on multisymplectic techniques has shown that boundary terms may occur in the constraint equations, unless some boundary conditions are imposed. This paper studies the corresponding form of such boundary terms in complex general relativity, where spacetime is a four-complex-dimensional complex-Riemannian manifold. A complex Ricci-flat spacetime is recovered providing some boundary conditions are imposed on two-complex-dimensional surfaces. One then finds that the holomorphic multimomenta should vanish on an arbitrary three-complex-dimensional surface, to avoid having restrictions at this surface on the spinor fields which express the invariance of the theory under holomorphic coordinate transformations. The Hamiltonian constraint of real general relativity is then replaced by a geometric structure linear in the holomorphic multimomenta, and a link with twistor theory is found. Moreover, a deep relation emerges between complex spacetimes which are not anti-self-dual and two-complex-dimensional surfaces which are not totally null.

Relativity, spherical functions and the hypergeometric equation

Abstract: Outre sa position centrale en physique, la relativite restreinte ouvre la voie a des faits mathematiques nouveaux. Partant du calcul de Klein-Gordon, un analogue relativiste du calcul de Weyl, on deforme ici la theorie des fonctions spheriques sur un espace symetrique de rang un ou, si l'on veut, celle des fonctions hypergeometriques

Special and General Relativity and Cosmology for Teachers and High-School Students

Abstract: The increasing distance between physics as taught at school and modern science has become a central problem of physics teaching. While our knowledge about physics increases every 8 or 10 years by a factor of about two, physics teaching very often suffers from obsolete contents and an overcharge with facts. Instead of emphasizing the concepts and intellectual contents with an eye for the cultural merits of physics, we very often become aware of switching over to still more technical applications.

Areg-2 experiments high-precision evidence for special relativity?

Abstract: An analysis of theg-2 experiments, which are often acclaimed as high-precision evidence for special relativity, is reported. The Lorentz factor γ = (1-v2 /c2)-1/2 calculated directly from the speed of particles is found to be numerically inconsistent with four alternately defined factors, γM,γt, γE, and γT, which in special relativity should all be equal to (1-v2/c2)-1/2. The analysis, herein, demonstrates that theg-2 experiments cannotdirectly verify special relativity withhigh precision as claimed.

An introduction to special relativity and its applications

Abstract: It is now nearly a century since relativity reconciled 17th century dynamics and 19th century electromagnetism, yet physics students are almost invariably introduced to the subject as "modern physics" and something of a mystery. This book, instead, treats special relativity as a useful branch of physics rather than as an astounding novelty. The emphasis is on its dynamical consequences, its effect on quantum mechanics (with all that this implies for chemistry and biology), the new insights that it provides in electromagnetism and its utility in problems such as calculating radiation from fast-moving charged particles. To avoid giving the impression that relativity somehow eliminates the distinction between time and space, 4-vector notation is not used until the latter part of the book. Since all the consequences of relativity arise from the Lorentz transformation, more than usual care is taken to show how it arises from simple notions about the uniformity of space and time, and the absence of any universal reference system at absolute rest. Recent studies in dynamics stress the critical difference between linearity and nonlinearity and so there is a proof that the transformation must be linear, something ignored by almost every other book on the subject.

Quaternions and Special Relativity

Abstract: We reformulate Special Relativity by a quaternionic algebra on reals. Using {\em real linear quaternions}, we show that previous difficulties, concerning the appropriate transformations on the $3+1$ space-time, may be overcome. This implies that a complexified quaternionic version of Special Relativity is a choice and not a necessity.

A Symmetry Approach to Time Dilation.

Abstract: Rather than introduce students to special relativity by starting from historical accounts, the approach outlined here uses a discussion of stopclocks and measurement of the transmission of light pulses to produce a natural derivation of the time dilation factor. A-level students should be able to follow this approach without difficulty.

Tests of Special Relativity with Laser Spectroscopy of Fast Atoms and IONS

Abstract: Testing special relativity (SR) has played its own and distinct role in physics for more than a century. So far no deviations from the predictions of SR has been detected despite the fact, that experimental tests of SR have traditionally belonged to the forefront of experimental physics employing the most advanced experimentation available at any given time1–5. Adding to this, no new theoretical developments have challenged the concept of relativity as described by Einstein early in this century. These observations raise the question, whether it makes sense to continue the search for possible violations of special relativity.

McGuire-Ruffini solution in new general relativity

Abstract: We obtain a solution of new general relativity from a solution of Einstein's general relativity which includes many known solutions, such as Kerr-Newman-Kasuya, Kerr-Newman, Kerr, and NUT, as special cases.

On the theory of high-velocity particles: A comment

Abstract: An argument claiming to prove two familiar consequences of special relativity, starting from the wave-particle duality of L. de Broglie, is found to be circular.