2005 saw the 100 year-anniversary since the paper "Zur Elektrodynamik bewegter Körper" by A. Einstein was published in Annalen der Physik, 1905, B. 17, S. 891. It is the most widely known and frequently cited paper from the series of works that underlay the Special Relative Theory (SRT). Those were the works by H.A. Lorentz "Electromagnetic phenomena in a system moving with any velocity smaller than that of light", Proceedings of Academy of Science, Amsterdam, 1904, V. 6, P. 809 and by H. Poincare "Sur la dynamique de lelectron", Comptes Rendus, 1905, V. 140, P. 1504 and "Sur la lelectron"', Rendiconti del Circolo Matematico di Palermo, 1906, V. XXI, P. 129 (to which reference was made in the monograph by A.A. Tyapkin "Principle of Relativity", Moscow, Atomizdat, 1973). The year of 1905 is commonly regarded by many as the year of the birth of the SRT. Considering its mathematical elegance, simplicity, succinctness and capacity for prediction, the SRT is a yet-unsurpassed example of fundamental theory in conjunction with remarkable achievements of human mind. Moreover, it is one of the few theories that have been supported by experiment. The experiments of the Michelson type, on which we shall dwell in more detail, were the most popular between them. By using the well-known optical interferometer, Michelson (1881) and Michelson and Morley (1887) discovered that, in the case of the Galilean velocity addition, the uppermost limit of the Ether wind occurring due to the orbital Earth motion did not exceed 10 km/s. In 1959, Cederholm and Townes constructed an interferometer including two ammonium masers and two He-Ne lasers. As a result, they found out that the Ether wind did not exceed 30 m/s. With the aid of the Mössbauer effect, Champeney and Moon (1961) came up with the Ether wind uppermost limit being as low as 17 m/s, while Champeney, Isaak and Khan (1963) brought that down to 1.6 m/s (5·10^-9 relative to the speed of light). According to the American Institute of Physics Bulletin of Physics News, No 590, May 21, 2002, the anisotropy of the speed of light is not higher than 1.7·10^-15. Experiment shows with an increasing precision that the speed of light does not depend on the direction of its propagation, which may be interpreted as constancy, or isotropy, of the speed of light. The less known, but not less important, experiments, are the Fizeau experiment, those run on determination of the angular light aberration, transverse Doppler effect measurements, and those carried out to prove independence of the speed of light from the velocity of light source, as well as certain others that shall not be discussed here.

The SRT has turned out to be closely associated with such objects as non-linear equations of the theoretical and mathematical physics. These equations attract much attention due to their specific properties such as the absence of the superposition principle, the non-linear field interactions, an existence of the soliton solutions. Mie (1912) was the first one to indicate the feasibility of such equations in the electrodynamics based on the theory of invariants of electromagnetic fields of the types E²-H² and EH². Particular versions of the equations were proposed, for example, by Born (1934) and Born and Infeld (1934). These equations enable to obtain the correct relationship of momentum vs. energy for the moving electric charge, hardly ever obtainable within the linear electrodynamics. In spite of the fact that those equations were not used commonly, the ideas inherent in them, saved the day. In this way, resorting to the non-linear components within decomposition of the Lagrange function density (radiative corrections) has become of use in the quantum electrodynamics. This made it possible to calculate the contribution of fine effects such as deviation from the Coulomb law at short distances and the transverse cross-section of scattering of light on light: the phenomenon that is basically impossible in the linear electrodynamics because of the superposition principle.

All in all, the SRT forms the baseline foundation of the modern theoretical physics. Without using the SRT, it is inconceivable to investigate the properties of microcosm, to do studies in nuclear and particle physics, nor to understand the operation of modern accelerators, either. It is an attractive subject for pursuing research in the Humanities: the possibility is there to impart the philosophical sense to the time dilatation, the shortening of lengths, the twin paradox, the famous Einstein mass-energy relationship. For science fiction writers, it bears on the traveling into distant future in ultra relativistic rockets, while for school children, it is a pain in the neck at physics classes. It may be said that the SRT has become part of the human culture.

The question arises as to whether it was possible to expand on this theory later on. In 1916, the answer to this question was partially supplied by A. Einstein with his subsequent creation of the General Relativity Theory (GRT). It lays in changeover from the pseudo-Euclidean spaces to the pseudo-Romanian spaces in which the metric tensor components depended on the space-time point coordinates of event. As a result, a resplendent theoretical-philosophical structure had been derived that contained the GRT and allied theories devoted to the problems of gravitation. But, what can be said about plane spaces? We can establish for a fact that in this case, too, works that regard a possibility of exceeding the SRT scope see the light periodically enough. It has turned out that there are some real possibilities here.

They are conditioned by mathematical properties of the SRT. The crux of the matter here is that the SRT had been formulated as the Lorentz invariant theory in the plane 4D Minkowski space with two postulates: the invariance of the metric ds'²=ds², and the invariance of the speed of light c'=c.

Getting beyond the scope of these postulates, as well as changing over to the spaces of a higher dimensionality or to the spaces of a different structure (for example, to the Finsler spaces) will imply a possibility of constructing a theory that differs from the SRT. In this way, in the limit case, the SRT can be re-obtainable anew just as the Newton mechanics is realizable in the relativistic physics within slow velocities v ???c. It should be said that this kind of research is published on occasion. The changeover to the conformal transformations in a space with the metric ds'²=σ^-2ds², where σ(x)=1-2ax+a²x², a⁰, a^{1,2,3} are the group parameters, has evoked a large response in periodicals on the conformanl invariant generalization of the field theory with the constant speed of light. Turning to a space with the metric properties ds'²=ds² is connected with the theory of superluminal motions. Changing to the more general groups of transformations with c'≠c, including the Lorentz group as a subgroup on the hyper-plane c=Const, has permitted to put forth such theoretical constructions that are different from the SRT. The level of research discussion in this issue and the number of its predictions is not yet sufficient to compare those comprehensively with the predictions of the SRT, although, fundamentally, it can be done so. It is the subject-matter of subsequent studies, which will, probably, be of interest to the Reader of the Journal. The Authors of the papers presented in the Journal and its Editors will gladly accept any remarks from its readers.

References

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