A 1% Measurement of the Gravitomagnetic Field of the Earth with Laser-Tracked Satellites
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Symmetry and Gravity
universe Article Making a Quantum Universe: Symmetry and Gravity Houri Ziaeepour 1,2 1 Institut UTINAM, CNRS UMR 6213, Observatoire de Besançon, Université de Franche Compté, 41 bis ave. de l’Observatoire, BP 1615, 25010 Besançon, France; [email protected] or [email protected] 2 Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking GU5 6NT, UK Received: 05 September 2020; Accepted: 17 October 2020; Published: 23 October 2020 Abstract: So far, none of attempts to quantize gravity has led to a satisfactory model that not only describe gravity in the realm of a quantum world, but also its relation to elementary particles and other fundamental forces. Here, we outline the preliminary results for a model of quantum universe, in which gravity is fundamentally and by construction quantic. The model is based on three well motivated assumptions with compelling observational and theoretical evidence: quantum mechanics is valid at all scales; quantum systems are described by their symmetries; universe has infinite independent degrees of freedom. The last assumption means that the Hilbert space of the Universe has SUpN Ñ 8q – area preserving Diff.pS2q symmetry, which is parameterized by two angular variables. We show that, in the absence of a background spacetime, this Universe is trivial and static. Nonetheless, quantum fluctuations break the symmetry and divide the Universe to subsystems. When a subsystem is singled out as reference—observer—and another as clock, two more continuous parameters arise, which can be interpreted as distance and time. We identify the classical spacetime with parameter space of the Hilbert space of the Universe. -
On the Status of the Geodesic Principle in Newtonian and Relativistic Physics1
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by PhilSci Archive On the Status of the Geodesic Principle in Newtonian and Relativistic Physics1 James Owen Weatherall2 Logic and Philosophy of Science University of California, Irvine Abstract A theorem due to Bob Geroch and Pong Soo Jang [\Motion of a Body in General Relativ- ity." Journal of Mathematical Physics 16(1), (1975)] provides a sense in which the geodesic principle has the status of a theorem in General Relativity (GR). I have recently shown that a similar theorem holds in the context of geometrized Newtonian gravitation (Newton- Cartan theory) [Weatherall, J. O. \The Motion of a Body in Newtonian Theories." Journal of Mathematical Physics 52(3), (2011)]. Here I compare the interpretations of these two the- orems. I argue that despite some apparent differences between the theorems, the status of the geodesic principle in geometrized Newtonian gravitation is, mutatis mutandis, strikingly similar to the relativistic case. 1 Introduction The geodesic principle is the central principle of General Relativity (GR) that describes the inertial motion of test particles. It states that free massive test point particles traverse timelike geodesics. There is a long-standing view, originally due to Einstein, that the geodesic principle has a special status in GR that arises because it can be understood as a theorem, rather than a postulate, of the theory. (It turns out that capturing the geodesic principle as a theorem in GR is non-trivial, but a result due to Bob Geroch and Pong Soo Jang (1975) 1Thank you to David Malament and Jeff Barrett for helpful comments on a previous version of this paper and for many stimulating conversations on this topic. -
Kaluza-Klein Gravity, Concentrating on the General Rel- Ativity, Rather Than Particle Physics Side of the Subject
Kaluza-Klein Gravity J. M. Overduin Department of Physics and Astronomy, University of Victoria, P.O. Box 3055, Victoria, British Columbia, Canada, V8W 3P6 and P. S. Wesson Department of Physics, University of Waterloo, Ontario, Canada N2L 3G1 and Gravity Probe-B, Hansen Physics Laboratories, Stanford University, Stanford, California, U.S.A. 94305 Abstract We review higher-dimensional unified theories from the general relativity, rather than the particle physics side. Three distinct approaches to the subject are identi- fied and contrasted: compactified, projective and noncompactified. We discuss the cosmological and astrophysical implications of extra dimensions, and conclude that none of the three approaches can be ruled out on observational grounds at the present time. arXiv:gr-qc/9805018v1 7 May 1998 Preprint submitted to Elsevier Preprint 3 February 2008 1 Introduction Kaluza’s [1] achievement was to show that five-dimensional general relativity contains both Einstein’s four-dimensional theory of gravity and Maxwell’s the- ory of electromagnetism. He however imposed a somewhat artificial restriction (the cylinder condition) on the coordinates, essentially barring the fifth one a priori from making a direct appearance in the laws of physics. Klein’s [2] con- tribution was to make this restriction less artificial by suggesting a plausible physical basis for it in compactification of the fifth dimension. This idea was enthusiastically received by unified-field theorists, and when the time came to include the strong and weak forces by extending Kaluza’s mechanism to higher dimensions, it was assumed that these too would be compact. This line of thinking has led through eleven-dimensional supergravity theories in the 1980s to the current favorite contenders for a possible “theory of everything,” ten-dimensional superstrings. -
Geometrodynamics of Gauge Fields on the Geometry of Yang-Mills and Gravitational Gauge Theories
springer.com Physics : Classical and Quantum Gravitation, Relativity Theory Mielke, Eckehard W. Geometrodynamics of Gauge Fields On the Geometry of Yang-Mills and Gravitational Gauge Theories A comprehensive revision of a classic text relating geometic field theory to modern physics Offers an up-to-date overview of geometrodynamics including minimal topological models Contains new chapters on teleparalelism, Chern-Simons-induced topological 3D gravity and supergravity, quantization via topological ghosts, constrained BF model with SL (5, R) gauge group, and chiral and trace anomalies Provides a detailed exposition of frame bundles in gravity Springer This monograph aims to provide a unified, geometrical foundation of gauge theories of 2nd ed. 2017, XVII, 373 p. elementary particle physics. The underlying geometrical structure is unfolded in a coordinate- 2nd 18 illus., 8 illus. in color. free manner via the modern mathematical notions of fibre bundles and exterior forms. Topics edition such as the dynamics of Yang-Mills theories, instanton solutions and topological invariants are included. By transferring these concepts to local space-time symmetries, generalizations of Einstein's theory of gravity arise in a Riemann-Cartan space with curvature and torsion. It Printed book provides the framework in which the (broken) Poincarégauge theory, the Rainich geometrization Hardcover of the Einstein-Maxwell system, and higher-dimensional, non-abelian Kaluza-Klein theories are Printed book developed. Since the discovery of the Higgs boson, concepts of spontaneous symmetry breaking in gravity have come again into focus, and, in this revised edition, these will be Hardcover exposed in geometric terms. Quantizing gravity remains an open issue: formulating it as a de ISBN 978-3-319-29732-3 Sitter type gauge theory in the spirit of Yang-Mills, some new progress in its topological form is £ 109,99 | CHF 141,50 | 119,99 € | presented. -
“Geodesic Principle” in General Relativity∗
A Remark About the “Geodesic Principle” in General Relativity∗ Version 3.0 David B. Malament Department of Logic and Philosophy of Science 3151 Social Science Plaza University of California, Irvine Irvine, CA 92697-5100 [email protected] 1 Introduction General relativity incorporates a number of basic principles that correlate space- time structure with physical objects and processes. Among them is the Geodesic Principle: Free massive point particles traverse timelike geodesics. One can think of it as a relativistic version of Newton’s first law of motion. It is often claimed that the geodesic principle can be recovered as a theorem in general relativity. Indeed, it is claimed that it is a consequence of Einstein’s ∗I am grateful to Robert Geroch for giving me the basic idea for the counterexample (proposition 3.2) that is the principal point of interest in this note. Thanks also to Harvey Brown, Erik Curiel, John Earman, David Garfinkle, John Manchak, Wayne Myrvold, John Norton, and Jim Weatherall for comments on an earlier draft. 1 ab equation (or of the conservation principle ∇aT = 0 that is, itself, a conse- quence of that equation). These claims are certainly correct, but it may be worth drawing attention to one small qualification. Though the geodesic prin- ciple can be recovered as theorem in general relativity, it is not a consequence of Einstein’s equation (or the conservation principle) alone. Other assumptions are needed to drive the theorems in question. One needs to put more in if one is to get the geodesic principle out. My goal in this short note is to make this claim precise (i.e., that other assumptions are needed). -
Gravitation Law and Source Model in the Anisotropic Geometrodynamics
Gravitation law and source model in the anisotropic geometrodynamics Sergey Siparov State University of Civil Aviation, 38 Pilotov str., St-Petersburg, 196210; Research Institute for Hyper Complex Systems in Geometry and Physics, 3 bg 1 Zavodskoy pr., Fryazino, Moscow region, 141190; Russian Federation Abstract. The GRT modification taking into account the dependence of metric on the velocities of the sources is built. It is shown that this dependence follows from the equivalence principle and from the inseparability of the field equations and geodesics equations. As it is known, the latter are the conditions of the field equations solvability, and their form coincides with Newtonian one only in the lowest approximation. The obtained modification provides the explanation for the flat character of the rotation curves of spiral galaxies, for Tully-Fisher law, for some specific features of globular clusters behavior and for the essential excess of the observable gravitational lens effect over the predicted one. Neither dark matter nor arbitrary change of dynamics equations appeared to be needed. Important cosmological consequences are obtained. Keywords: modified theory of gravity, rotation curves, Tully-Fisher law, anisotropic metric PACS: 04.20.Cv, 04.50.Kd, 95.30.Sf, 98.20.Gm, 98.52.Nr, 98.80.Es 1. INTRODUCTION The flat character of the rotation curves (RC) of spiral galaxies is the most pronounced problem of the known GRT problems on the galactic scale. This is a simple, not small and statistically verified effect which doesn’t find explanation not only in the GRT but in Newton gravity as well. It is to the fact that the orbital velocities of stars in the spiral galaxies don’t tend to zero with the distance from the center but approach constant values of the order 105m/s for all galaxies. -
Do Global Virtual Axionic Gravitons Exist?
NeuroQuantology | March 2014 | Volume 12 | Issue 1 | Page 35-39 35 Glinka LA., Do global virtual axionic gravitons exist? Do Global Virtual Axionic Gravitons Exist? Lukasz Andrzej Glinka ABSTRACT Recently, the author has proposed the global one-dimensionality conjecture which, throughout making use of the method of the primary canonical quantization of General Relativity according to the Dirac-Arnowitt-Deser-Misner Hamiltonian formulation, formally avoids the functional differential nature which is the basic obstacle of quantum geometrodynamics, a model of quantum gravity based on the Wheeler-DeWitt equation and resutling from quantization of the Einstein field equations. The emergent quantum gravity model is straightforwardly integrable in terms of the Riemann-Lebesgue integral, has an unambiguous physical interpretation within quantum theory, and introduces a consistent concept of global graviton. In this article, the axionic nature of the global gravitons, that is the hypothetical particles responsible for gravitation in the global one-dimensional quantum gravity model, is shortly described and, making use of fundamental methods of quantum field theory, the virtual states of such gravitons are generated. Key Words: global one-dimensionality conjecture; quantum gravity; quantum geometrodynamics; graviton; axion DOI Number: 10.14704/nq.2014.12.1.716 NeuroQuantology 2014; 1: 35-39 1. Introduction1 results in replacement of the functional Recently the Wheeler-DeWitt equation was evolution parameter which is the metric of considered in the framework of the global one- space by a variable which is the metric dimensionality conjecture (Glinka, 2012; 2010). determinant. The ramifications of this change Recall that this conjecture formally reduces the are highly non-trivial. -
Tensor-Spinor Theory of Gravitation in General Even Space-Time Dimensions
Physics Letters B 817 (2021) 136288 Contents lists available at ScienceDirect Physics Letters B www.elsevier.com/locate/physletb Tensor-spinor theory of gravitation in general even space-time dimensions ∗ Hitoshi Nishino a, ,1, Subhash Rajpoot b a Department of Physics, College of Natural Sciences and Mathematics, California State University, 2345 E. San Ramon Avenue, M/S ST90, Fresno, CA 93740, United States of America b Department of Physics & Astronomy, California State University, 1250 Bellflower Boulevard, Long Beach, CA 90840, United States of America a r t i c l e i n f o a b s t r a c t Article history: We present a purely tensor-spinor theory of gravity in arbitrary even D = 2n space-time dimensions. Received 18 March 2021 This is a generalization of the purely vector-spinor theory of gravitation by Bars and MacDowell (BM) in Accepted 9 April 2021 4D to general even dimensions with the signature (2n − 1, 1). In the original BM-theory in D = (3, 1), Available online 21 April 2021 the conventional Einstein equation emerges from a theory based on the vector-spinor field ψμ from a Editor: N. Lambert m lagrangian free of both the fundamental metric gμν and the vierbein eμ . We first improve the original Keywords: BM-formulation by introducing a compensator χ, so that the resulting theory has manifest invariance = =− = Bars-MacDowell theory under the nilpotent local fermionic symmetry: δψ Dμ and δ χ . We next generalize it to D Vector-spinor (2n − 1, 1), following the same principle based on a lagrangian free of fundamental metric or vielbein Tensors-spinors rs − now with the field content (ψμ1···μn−1 , ωμ , χμ1···μn−2 ), where ψμ1···μn−1 (or χμ1···μn−2 ) is a (n 1) (or Metric-less formulation (n − 2)) rank tensor-spinor. -
Einstein, Nordström and the Early Demise of Scalar, Lorentz Covariant Theories of Gravitation
JOHN D. NORTON EINSTEIN, NORDSTRÖM AND THE EARLY DEMISE OF SCALAR, LORENTZ COVARIANT THEORIES OF GRAVITATION 1. INTRODUCTION The advent of the special theory of relativity in 1905 brought many problems for the physics community. One, it seemed, would not be a great source of trouble. It was the problem of reconciling Newtonian gravitation theory with the new theory of space and time. Indeed it seemed that Newtonian theory could be rendered compatible with special relativity by any number of small modifications, each of which would be unlikely to lead to any significant deviations from the empirically testable conse- quences of Newtonian theory.1 Einstein’s response to this problem is now legend. He decided almost immediately to abandon the search for a Lorentz covariant gravitation theory, for he had failed to construct such a theory that was compatible with the equality of inertial and gravitational mass. Positing what he later called the principle of equivalence, he decided that gravitation theory held the key to repairing what he perceived as the defect of the special theory of relativity—its relativity principle failed to apply to accelerated motion. He advanced a novel gravitation theory in which the gravitational potential was the now variable speed of light and in which special relativity held only as a limiting case. It is almost impossible for modern readers to view this story with their vision unclouded by the knowledge that Einstein’s fantastic 1907 speculations would lead to his greatest scientific success, the general theory of relativity. Yet, as we shall see, in 1 In the historical period under consideration, there was no single label for a gravitation theory compat- ible with special relativity. -
Plasma Modes in Surrounding Media of Black Holes and Vacuum Structure - Quantum Processes with Considerations of Spacetime Torque and Coriolis Forces
COLLECTIVE COHERENT OSCILLATION PLASMA MODES IN SURROUNDING MEDIA OF BLACK HOLES AND VACUUM STRUCTURE - QUANTUM PROCESSES WITH CONSIDERATIONS OF SPACETIME TORQUE AND CORIOLIS FORCES N. Haramein¶ and E.A. Rauscher§ ¶The Resonance Project Foundation, [email protected] §Tecnic Research Laboratory, 3500 S. Tomahawk Rd., Bldg. 188, Apache Junction, AZ 85219 USA Abstract. The main forces driving black holes, neutron stars, pulsars, quasars, and supernovae dynamics have certain commonality to the mechanisms of less tumultuous systems such as galaxies, stellar and planetary dynamics. They involve gravity, electromagnetic, and single and collective particle processes. We examine the collective coherent structures of plasma and their interactions with the vacuum. In this paper we present a balance equation and, in particular, the balance between extremely collapsing gravitational systems and their surrounding energetic plasma media. Of particular interest is the dynamics of the plasma media, the structure of the vacuum, and the coupling of electromagnetic and gravitational forces with the inclusion of torque and Coriolis phenomena as described by the Haramein-Rauscher solution to Einstein’s field equations. The exotic nature of complex black holes involves not only the black hole itself but the surrounding plasma media. The main forces involved are intense gravitational collapsing forces, powerful electromagnetic fields, charge, and spin angular momentum. We find soliton or magneto-acoustic plasma solutions to the relativistic Vlasov equations solved in the vicinity of black hole ergospheres. Collective phonon or plasmon states of plasma fields are given. We utilize the Hamiltonian formalism to describe the collective states of matter and the dynamic processes within plasma allowing us to deduce a possible polarized vacuum structure and a unified physics. -
What Is Gravity Probe B?
What is Gravity Probe B? Gravity Probe B (GP-B) is a NASA physics mission to experimentally in• William Fairbank once remarked: “No mission could be sim• vestigate Einstein’s 1916 general theory of relativity—his theory of gravity. pler than Gravity Probe B. It’s just a star, a telescope, and a spin• GB-B uses four spherical gyroscopes and a telescope, housed in a satellite ning sphere.” However, it took the exceptional collaboration of Stan• orbiting 642 km (400 mi) above the Earth, to measure, with unprecedented ford, MSFC, Lockheed Martin and a host of others more than four accuracy, two extraordinary effects predicted by the general theory of rela• decades to develop the ultra-precise gyroscopes and the other cut• tivity: 1) the geodetic effect—the amount by which the Earth warps the local ting-edge technologies necessary to carry out this “simple” experiment. spacetime in which it resides; and 2) the frame-dragging effect—the amount by which the rotating Earth drags its local spacetime around with it. GP-B tests these two effects by precisely measuring the precession (displacement) The GP-B Flight Mission angles of the spin axes of the four gyros over the course of a year and com• paring these experimental results with predictions from Einstein’s theory. On April 20, 2004 at 9:57:24 AM PDT, a crowd of over 2,000 current and former GP-B team members and supporters watched and cheered as the A Quest for Experimental Truth GP-B spacecraftlift ed offf rom Vandenberg Air Force Base. -
Chapter 1 Introduction
Chapter 1 Introduction 1.1 Introduction Einsteins theory of general relativity (GR) [Einstein, 1915b,a, de Sitter, 1917, Silberstein, 1917] together with quantum field theory are considered to be the pillars of modern physics. GR deals with gravitational phenomena treating space-time as a four-dimensional manifold. The theory has a well understood and mathematically very elegant structure and is internally consistent. GR describes gracefully all the experimental tests of gravity [Weinberg, 1972, Berti et al., 2015] conducted till now without a single adjustable parameter. 1.2 General Relativity The inverse-square gravitational force law introduced by Newton predicted cor- rectly a variety of gravitational phenomena including planetary motion. In fact the 10 Chapter 1: Introduction 11 Newtons theory was very successful in describing all the known gravitational phe- nomena at that time. The first deviation from the Newtons theory was noticed in the precession of Mercurys orbit; a 43 arc-seconds per century excess precession over that given by Newtons theory was observed. However, not because of such small deviation in just one experimental results, Einstein developed General relativity to make the theory of gravitation consistent with Special Theory of Relativity (STR). Newtonian mechanics is based on the existence of absolute space and thereby absolute motion whereas STR rests on the idea that all (un-accelerated) motions are relative in nature. A consequent feature emerges in STR that no information can be transmitted with speed greater than the speed of light whereas the Newtons law of gravity implies action at a distance i.e. in Newtonian paradigm the gravita- tional information moves with infinite speed.