Prospects for observations of relativistic effects in the solar system

The solar system is the traditional laboratory for testing theories of gravitation. The results of all tests are consistent with the predictions of general relativity. The differences between these predictions and those of Newton's theory of gravitation have been confirmed with uncertainties as small as one part in a thousand. To enhance significantly the accuracy of such tests, one must investigate novel techniques. In this paper we concentrate on an experiment that promises a dramatic improvement in a classical test of general relativity – the deflection of light by solar gravity. The goal is to measure the post-post-Newtonian contribution of nearly 11 microarcseconds to this deflection. The technique we propose is based on use of an astrometric optical interferometer, POINTS, which could be operated from the bay of the Space Shuttle, mounted on the proposed Space Station, or supported by an independent spacecraft. POINTS should be able to measure the separation of stars about 90° apart with an uncertainty of only a few microarcseconds.

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On claims that general relativity differs from Newtonian physics for self-gravitating dusts in the low velocity, weak field limit

International Journal of Modern Physics D ◽

10.1142/s0218271815500650 ◽

2015 ◽

Vol 24 (08) ◽

pp. 1550065 ◽

Cited By ~ 5

Author(s):

David R. Rowland

Keyword(s):

General Relativity ◽

Solar System ◽

Relativistic Effects ◽

Weak Field ◽

Newtonian Gravity ◽

Galactic Rotation ◽

Low Velocity ◽

Rotation Curves ◽

Newtonian Physics ◽

General Relativistic

Galaxy rotation curves are generally analyzed theoretically using Newtonian physics; however, two groups of authors have claimed that for self-gravitating dusts, general relativity (GR) makes significantly different predictions to Newtonian physics, even in the weak field, low velocity limit. One group has even gone so far as to claim that nonlinear general relativistic effects can explain flat galactic rotation curves without the need for cold dark matter. These claims seem to contradict the well-known fact that the weak field, low velocity, low pressure correspondence limit of GR is Newtonian gravity, as evidenced by solar system tests. Both groups of authors claim that their conclusions do not contradict this fact, with Cooperstock and Tieu arguing that the reason is that for the solar system, we have test particles orbiting a central gravitating body, whereas for a galaxy, each star is both an orbiting body and a contributor to the net gravitational field, and this supposedly makes a difference due to nonlinear general relativistic effects. Given the significance of these claims for analyses of the flat galactic rotation curve problem, this article compares the predictions of GR and Newtonian gravity for three cases of self-gravitating dusts for which the exact general relativistic solutions are known. These investigations reveal that GR and Newtonian gravity are in excellent agreement in the appropriate limits, thus supporting the conventional use of Newtonian physics to analyze galactic rotation curves. These analyses also reveal some sources of error in the referred to works.

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RELATIVISTIC EFFECTS IN EXTRASOLAR PLANETARY SYSTEMS

International Journal of Modern Physics D ◽

10.1142/s0218271806009479 ◽

2006 ◽

Vol 15 (12) ◽

pp. 2133-2140 ◽

Cited By ~ 20

Author(s):

FRED C. ADAMS ◽

GREGORY LAUGHLIN

Keyword(s):

General Relativity ◽

Solar System ◽

Planetary Systems ◽

Relativistic Effects ◽

Interaction Theory ◽

Orbital Elements ◽

Secular Resonance ◽

The Future ◽

General Relativistic ◽

Temporal Coverage

This paper considers general relativistic (GR) effects in currently observed extrasolar planetary systems. Although GR corrections are small, they can compete with secular interactions in these systems and thereby play an important role. Specifically, some of the observed multiple planet systems are close to secular resonance, where the dynamics is extremely sensitive to GR corrections, and these systems can be used as laboratories to test general relativity. For the three-planet solar system Upsilon Andromedae, secular interaction theory implies an 80% probability of finding the system with its observed orbital elements if GR is correct, compared with only a 2% probability in the absence of GR. In the future, tighter constraints can be obtained with increased temporal coverage.

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Einstein’s General Theory of Relativity and the Development of Modified Theories of Gravitation

Physics and High Technology ◽

10.3938/phit.29.038 ◽

2020 ◽

Vol 29 (11) ◽

pp. 2-9

Author(s):

Bogeun GWAK, ◽

Bum-Hoon LEE ◽

Wonwoo LEE

Keyword(s):

General Relativity ◽

Dark Matter ◽

Dark Energy ◽

General Theory ◽

Quantum Gravity ◽

Theory Of Relativity ◽

General Theory Of Relativity ◽

Theory Of Gravitation ◽

Wave Dark Matter ◽

Theories Of Gravitation

We briefly review both Einstein’s general theory of relativity and the development of modified theories of gravitation with theoretical and observational motivations. For this, we discuss the theoretical properties and weaknesses of general relativity. We also mention attempts that have been made to develop the theory of quantum gravity. The recent detections of a gravitational wave, dark matter, and dark energy have opened new windows into astrophysics, as well as cosmology, through which tests to determine the theory of gravitation that best describes our Universe would be interesting. Most of all, note that we cannot clearly describe our Universe, including dark matter and dark energy, with standard particle models and the general theory of relativity. In these respects, we must be open-minded and study all possible aspects.

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Simulation of general relativistic corrections in long term numerical integrations of planetary orbits

Symposium - International Astronomical Union ◽

10.1017/s0074180900148053 ◽

1986 ◽

Vol 114 ◽

pp. 105-111

Author(s):

Anna M. Nobili ◽

Ian W. Roxburgh

Keyword(s):

General Relativity ◽

Solar System ◽

Computer Time ◽

Substantial Improvement ◽

Numerical Integrations ◽

Planetary Orbits ◽

General Relativistic ◽

Theory Of Gravitation ◽

The Stability

Long term numerical integrations of planetary orbits designed to study the stability of the Solar System over timescales comparable to its age have become very promising thanks to the availability of very powerful computers and to a substantial improvement in our methods of investigating the stability of hierarchical dynamical systems. The stability of such numerical integrations relies on the ability to control all possible sources of error. Among the errors caused by the inadequacy of the physical model are those due to the fact that Newton's theory of gravitation is used instead of general relativity. We show that the secular advance of perihelia predicted by general relativity can be simulated exactly by a 1/r2 perturbing potential with almost negligible additional cost in computer time.

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The constancy of G and other gravitational experiments

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1983.0083 ◽

1983 ◽

Vol 310 (1512) ◽

pp. 227-238 ◽

Cited By ~ 39

Keyword(s):

General Relativity ◽

Solar System ◽

Relativistic Effects ◽

Delay Effect ◽

Data Set ◽

Gravitomagnetic Field ◽

Test Technology ◽

Stringent Test ◽

Data Yield ◽

Time Delay Effect

Traditionally, theories of gravitation have received their most demanding tests in the solar-system laboratory. Today, electronic observing technology makes possible solar system tests of substantially increased accuracy. We consider how these technologies are being used to study gravitation with an emphasis on two questions: (i) Dirac and others have investigated theories in which the constant of gravitation, G , appears to change with time. Recent analyses using the Viking data yield | G / G | < 3 x 10 -11 per year. With further analysis, the currently available ensemble of data should permit an estimate of G/G with an uncertainty of 10 -11 per year. At this level it will become possible to distinguish among competitive theories. (ii) Shapiro’s time-delay effect has provided the most stringent solar-system test of general relativity. The effect has been measured to be consistent with the predictions of general relativity with a fractional uncertainty of 0.1%. An improved analysis of an enhanced data set should soon permit an even more stringent test. Technology now permits new kinds of tests to be performed. Among these are some that measure relativistic effects due to the square of the (solar) potential and others that detect the Earth’s ‘gravitomagnetic’ field (the Lense-Thirring effect). These experiments, and the use of astrophysical systems are among the experimental challenges for the coming decades.

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THE SCALAR ETHER-THEORY OF GRAVITATION AND ITS FIRST TEST IN CELESTIAL MECHANICS

International Journal of Modern Physics A ◽

10.1142/s0217751x0201323x ◽

2002 ◽

Vol 17 (29) ◽

pp. 4203-4208 ◽

Cited By ~ 3

Author(s):

MAYEUL ARMINJON

Keyword(s):

General Relativity ◽

Scalar Field ◽

Solar System ◽

Celestial Mechanics ◽

Equations Of Motion ◽

Alternative Interpretation ◽

Crucial Point ◽

Ether Theory ◽

Theory Of Gravitation ◽

Basic Equations

The motivations for investigating a theory of gravitation based on a concept of "ether" are discussed — a crucial point is the existence of an alternative interpretation of special relativity, named the Lorentz-Poincaré ether theory. The basic equations of one such theory of gravity, based on just one scalar field, are presented. To check this theory in celestial mechanics, an "asymptotic" scheme of post-Newtonian (PN) approximation is summarized and its difference with the standard PN scheme is emphasized. The derivation of PN equations of motion for the mass centers, based on the asymptotic scheme, is outlined. They are implemented for the major bodies of the solar system and the prediction for Mercury is compared with an ephemeris based on general relativity.

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EVA 2010: Preparing for International Space Station EVA Operations Post-Space Shuttle Retirement

40th International Conference on Environmental Systems ◽

10.2514/6.2010-6130 ◽

2010 ◽

Cited By ~ 1

Author(s):

William West ◽

Vincent Witt ◽

Cinda Chullen

Keyword(s):

International Space Station ◽

Space Shuttle ◽

Space Station ◽

International Space ◽

Post Space

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Beyond the Schwarzschild Metric

10.1093/oso/9780199658633.003.0019 ◽

2018 ◽

Author(s):

David M. Wittman

Keyword(s):

Black Holes ◽

General Relativity ◽

Gravitational Waves ◽

Test Particle ◽

Direct Detection ◽

Relativistic Effects ◽

Big Bang ◽

Clusters Of Galaxies ◽

General Relativistic ◽

The Universe

General relativity explains much more than the spacetime around static spherical masses.We briefly assess general relativity in the larger context of physical theories, then explore various general relativistic effects that have no Newtonian analog. First, source massmotion gives rise to gravitomagnetic effects on test particles.These effects also depend on the velocity of the test particle, which has substantial implications for orbits around black holes to be further explored in Chapter 20. Second, any changes in the sourcemass ripple outward as gravitational waves, and we tell the century‐long story from the prediction of gravitational waves to their first direct detection in 2015. Third, the deflection of light by galaxies and clusters of galaxies allows us to map the amount and distribution of mass in the universe in astonishing detail. Finally, general relativity enables modeling the universe as a whole, and we explore the resulting Big Bang cosmology.

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