The Genesis of General Relativity: Volume 4 (original) (raw)
The Renaissance of General Relativity: How and Why it Happened.”
Annalen der Physik, 2016
After an initial burst of excitement about its extraordinary implications for our concept of space and time, the theory of general relativity underwent a thirty-year period of stagnation, during which only a few specialists worked on it, achieving little progress. In the aftermath of World War II, however, general relativity gradually re-entered the mainstream of physics, attracting an increasing number of practitioners and becoming the basis for the current standard theory of gravitation and cosmology-a process Clifford Will baptized the Renaissance of General Relativity. The recent detection of gravitational radiation by the LIGO experiment can be seen as one of the most outstanding achievements in this long-lasting historical process. In the paper, we present a new multifaceted historical perspective on the causes and characteristics of the Renaissance of General Relativity, focusing in particular on the case of gravitational radiation in order to illustrate this complex and far-reaching process.
Science & Education, 2009
The revolution in XX century physics, induced by relativity theories, had its roots within the electromagnetic conception of Nature. It was developed through a tradition related to Brunian and Leibnizian physics, to the German Naturphilosophie and English XIXth physics. The electromagnetic conception of Nature was in some way realized by the relativistic dynamics of Poincaré of 1905. Einstein, on the contrary, after some years, linked relativistic dynamics to a semi-mechanist conception of Nature. He developed general relativity theory on the same ground, but Hilbert formulated it starting from the electromagnetic conception of Nature. Here, a comparison between these two conceptions is proposed in order to understand the conceptual foundations of special relativity within the context of the changing world views. The whole history of physics as well as history of science can be considered as a conflict among different worldviews. Every theory, as well as every different formulation of a theory implies a different worldview: a particular image of Nature implies a particular image of God (atheism too has a particular image of God) as well as of mankind and of their relationship. Thus, it is very relevant for scientific education to point out which image of Nature belongs to a particular formulation of a theory, which image comes to dominate and for which ideological reason.
THE REVENGE OF HISTORY: TWO 19th CENTURY ALTERNATIVES TO SPECIAL RELATIVITY
Here are two rational alternatives to Special Relativity that preserve commonsense. Almost all of the dramatic results arising from the theory of special relativity derive from the kinematic consequences of the Lorentz transformation, especially with respect to its impact on the time dimension, where it appears to result in dynamical effects. An analysis of the Lorentz transformation herein shows that equally valid alternative kinematic assumptions lead to the earlier (1887) Voigt transform, which is usually viewed as simply equivalent to the Lorentz transform in the transverse spatial dimensions. This is shown NOT to be the case, and the Voigt transformations are shown to be much closer to the classical (Galilean) transforms. Einstein's derivation of the Lorentz transform is shown to rely on a critical, third hypothesis, namely one of symmetry between the two inertial reference frames; this assumption is shown not to be reflected in the actual physics of optical observations. It is also emphasized here that Relativity is a derived theory – being based on the validity of classical Maxwell electrodynamics. Although Maxwell's implicit assumption of continuity of electric charge has been shown by von Laue to be incompatible with the relativistic treatment of mass points, relativity has been universally accepted as the theory for treating point electrons. Planck's 1907 proposal for redefining the momentum of a particle is shown to be the critical foundation of relativistic particle dynamics, however, this proposal is independent of the Special Theory of Relativity and is neither derived from this theory nor do its results (including the infamous formula, E = mc 2) validate SRT. (Einstein's 1905 analysis of particle dynamics is incorrect and all of his attempts to derive the equivalence of mass and energy were failures.) However, Planck's proposal is shown to be valid only for electrostatic forces – a result that has major negative implications for all of today's quantum field theories. When the Voigt results are combined with Heaviside's 1888 results for delayed electromagnetic interactions between two moving charged particles, an understandable and consistent interpretation of these famous velocity-sensitive experiments is obtained. This demonstrates that the 'unusual' high-speed effects that are often attributed to relativity result only from " magnetic " effects becoming comparable to the " electric " ones. The combination of these two approaches, from almost forgotten 19th Century physicists, provides a new impetus for reexamining the delayed action-at-a-distance approach to electro-magnetism proposed first by Gauss, the greatest mathematician of this earlier century. This new coherent approach, when combined with a more fundamental 'Relativity Principle', provides a superior research program for consolidating the peculiar (velocity-sensitive) characteristics of the electromagnetic interaction with the velocity independent foundations of classical particle dynamics. This restores the natural philosophy of Isaac Newton, involving absolute space and absolute time, to a unified relativistic framework that should be viewed as a superior alternative to the contradictory and bizarre results of the Lorentz transformation derived from Maxwellian field theory and its 20th Century successors. The "rush to explanation", exemplified by using coordinate transformations to explain the increasing difficulty of accelerating charged particles as they increase their energy and extended unstable particle lifetimes at high velocities, has avoided the search for more realistic dynamical explanations of many high-velocity phenomena. In fact, particle lifetimes are the only physical 'evidence' for accepting the validity of the special theory of relativity as a universal basis for all of modern physics. However, even this result is contradicted by Planck's invariant quantum of action which all field theories (whether subject to Lorentz or Voigt transformations) predict to vary with relative velocity. In summary, the detailed analysis presented herein demonstrates that the special theory of relativity is, at best, an arbitrary theory of mathematical transformations divorced from the microphysical foundations of the electromagnetic phenomena it is supposedly based upon.
2021
For the layman, modern physics is like an immense and magnificent cathedral that is impressive in its complex and sophisticated architecture, and amazing in size and richness of the workmanship. Yet, in this apparently almost complete edifice, there is no answer to a long series of basic and crucial questions, while in any case these answers are indispensable and preliminary to any general theory. It is essential to avoid the confusion between appropriate and clarifying answers and false tautological answers or formulas that actually say nothing about the questions posed. In this book, the starting point is the interpretation given by Einstein’s general relativity to explain the gravitational force not as an action at a distance but as an effect intrinsic to the deformation of space caused by a “mass”. This interpretation is extended to the explanation of any attractive or repulsive force as an effect of flattening of dimensions with positive or negative curvature, one for each force. It offers, without any forcing, an explanation for most of the unsolved questions of physics, of the nature of a mass, matter and antimatter, of the structure of an atom, of the origin of natural constants, of the quantization of phenomena, etc. It also offers a different interpretation of the nature of electrons and black holes. Furthermore, the existence of antimatter in protons, but not in neutrons, is also predicted, a phenomenon that appears to be documented by recent works. This book is not written by a physicist but it is also highlighted why a professional physicist would have to overcome serious or insurmountable difficulties to give innovative answers to the fundamental unsolved problems of physics using concepts unrelated to those currently accepted.
The Formative Years of Relativity: The History and Meaning of Einstein's Princeton Lectures
2017
The Meaning of Relativity, also known as Four Lectures on Relativity, is Einstein's definitive exposition of his special and general theories of relativity. It was written in the early 1920s, a few years after he had elaborated his general theory of relativity. Neither before nor afterward did he offer a similarly comprehensive exposition that included not only the theory's technical apparatus but also detailed explanations making his achievement accessible to readers with a certain mathematical knowledge but no prior familiarity with relativity theory. In 1916, he published a review paper that provided the first condensed overview of the theory but still reflected many features of the tortured pathway by which he had arrived at his new theory of gravitation in late 1915. An edition of the manuscript of this paper with introductions and detailed commentaries on the discussion of its historical contexts can be found in The Road to Relativity. 1 Immediately afterward, Einstein wrote a nontechnical popular account, Relativity-The Special and General Theory. 2 Beginning with its first German edition, in 1917, it became a global bestseller and marked the first triumph of relativity theory as a broad cultural phenomenon. We have recently republished this book with extensive commentaries and historical contexts that document its global success. These early accounts, however, were able to present the theory only in its infancy. Immediately after its publication on 25 November 1915, Einstein's theory of general relativity was taken up, elaborated, and controversially discussed by his colleagues, who included physicists, mathematicians, astronomers, and philosophers. Einstein himself also made further fundamental contributions to the development of his theory, exploring consequences such as gravitational waves and cosmological solutions, elucidating concepts such as that of the energy and momentum of the gravitational field, and even reinterpreting basic aspects of the theory. A turning point was the confirmation of the bending of light in a gravitational field, which, as predicted by general relativity, was observed during a solar eclipse in 1919. These were the formative years of relativity in which the theory essentially received the structure in which it later became one of the pillars of modern physics. The Meaning of Relativity is the paradigmatic text of this period, reflecting not only Einstein's own efforts but also the engagement of his contemporaries with the theory. Einstein evidently returned to the theory of relativity in many later publications, both specialized and popular. He later also enriched The Meaning of Relativity with appendixes discussing further developments. But he never made another attempt at such an all-encompassing presentation in which he painstakingly motivated, explained, and discussed its basic principles and their consequences.