scholarly journals Solar System planetary orbital motions andf(R) theories of gravity

2007 ◽  
Vol 2007 (01) ◽  
pp. 010-010 ◽  
Author(s):  
Matteo Luca Ruggiero ◽  
Lorenzo Iorio
Keyword(s):  
Solar System ◽  
Theories Of Gravity

scholarly journals Testing the Vainshtein mechanism using stars and galaxies

2015 ◽  
Vol 24 (12) ◽  
pp. 1544021 ◽  
Author(s):  
Jeremy Sakstein ◽  
Kazuya Koyama
Keyword(s):  
General Relativity ◽  
Solar System ◽  
Main Sequence ◽  
Alternative Theories Of Gravity ◽  
The Novel ◽  
Main Sequence Stars ◽  
Cosmic Expansion ◽  
Astrophysical Objects ◽  
Theories Of Gravity ◽  
Alternative Theories

The Vainshtein mechanism is of paramount importance in many alternative theories of gravity. It hides deviations from general relativity (GR) in the solar system while allowing them to drive the acceleration of the cosmic expansion. Recently, a class of theories have emerged where the mechanism is broken inside astrophysical objects. In this essay, we look for novel probes of these theories by deriving the modified properties of stars and galaxies. We show that main-sequence stars are colder, less luminous and more ephemeral than GR predicts. Furthermore, the circular velocities of objects orbiting inside galaxies are slower and the lensing of light is weaker. We discuss the prospects for testing these theories using the novel phenomena presented here in light of current astrophysical surveys.

scholarly journals Gravitoelectromagnetism, Solar System Tests, and Weak-Field Solutions in f (T,B) Gravity with Observational Constraints

Universe ◽  
2020 ◽  
Vol 6 (2) ◽  
pp. 34 ◽  
Author(s):  
Gabriel Farrugia ◽  
Jackson Levi Said ◽  
Andrew Finch
Keyword(s):  
Solar System ◽  
Teleparallel Gravity ◽  
Weak Field ◽  
Observational Constraints ◽  
Field Limit ◽  
Potential Models ◽  
Weak Field Limit ◽  
Rotating Systems ◽  
Theories Of Gravity ◽  
Analogous Effect

Gravitomagnetism characterizes phenomena in the weak-field limit within the context of rotating systems. These are mainly manifested in the geodetic and Lense-Thirring effects. The geodetic effect describes the precession of the spin of a gyroscope in orbit about a massive static central object, while the Lense-Thirring effect expresses the analogous effect for the precession of the orbit about a rotating source. In this work, we explore these effects in the framework of Teleparallel Gravity and investigate how these effects may impact recent and future missions. We find that teleparallel theories of gravity may have an important impact on these effects which may constrain potential models within these theories.

scholarly journals SCIENTIFIC POTENTIAL OF DECIGO PATHFINDER AND TESTING GR WITH SPACE-BORNE GRAVITATIONAL WAVE INTERFEROMETERS

2013 ◽  
Vol 22 (01) ◽  
pp. 1341013 ◽  
Author(s):  
KENT YAGI
Keyword(s):  
Solar System ◽  
Gravitational Wave ◽  
Strong Field ◽  
Alternative Theories Of Gravity ◽  
Black Hole Binaries ◽  
Future Space ◽  
Stringent Constraint ◽  
Scientific Potential ◽  
Theories Of Gravity ◽  
Alternative Theories

Deci-Hertz Interferometer Gravitational Wave Observatory (DECIGO) Pathfinder (DPF) has an ability to detect gravitational waves (GWs) from galactic intermediate mass black hole binaries. If the signal is detected, it would be possible to determine parameters of the binary components. Furthermore, by using future space-borne GW interferometers, it would be possible to test alternative theories of gravity in the strong field regime. In this review paper, we first explain how the detectors like DPF and DECIGO/BBO work and discuss the expected event rates. Then, we review how the observed gravitational waveforms from precessing compact binaries with slightly eccentric orbits can be calculated both in general relativity and in alternative theories of gravity. For the latter, we focus on Brans–Dicke (BD) and massive gravity (MG) theories. After reviewing these theories, we show the results of the parameter estimation with DPF using the Fisher analysis. We also discuss a possible joint search of DPF and ground-based interferometers. Then, we show the results of testing alternative theories of gravity using future space-borne interferometers. DECIGO/BBO would be able to place 4–5 orders of magnitude stronger constraint on BD theory than the solar system experiment. This is still 1–2 orders of magnitude stronger than the future solar system mission such as ASTROD I. On the other hand, LISA should be able to put four orders of magnitude more stringent constraint on the mass of the graviton than the current solar system bound. DPF may be able to place comparable constraint on the MG theories as the solar system bound. We also discuss the prospects of using eLISA and ASTROD-GW in testing alternative theories of gravity. The bounds using eLISA are similar to the LISA ones, but ASTROD-GW performs the best in constraining MG theories among all the GW detectors considered in this paper.

scholarly journals Detecting modified gravity in the stars

2014 ◽  
Vol 23 (12) ◽  
pp. 1442002 ◽  
Author(s):  
Jeremy Sakstein ◽  
Bhuvnesh Jain ◽  
Vinu Vikram
Keyword(s):  
Solar System ◽  
Modified Gravity ◽  
Dwarf Galaxies ◽  
Cosmic Acceleration ◽  
Modified Theories Of Gravity ◽  
Small Scales ◽  
Theories Of Gravity ◽  
Tests Of Gravity

Modified theories of gravity have received a renewed interest due to their ability to account for the cosmic acceleration. In order to satisfy the solar system tests of gravity, these theories need to include a screening mechanism that hides the modifications on small scales. One popular and well-studied theory is chameleon gravity. Our own galaxy is necessarily screened, but less dense dwarf galaxies may be unscreened and their constituent stars can exhibit novel features. In particular, unscreened stars are brighter, hotter and more ephemeral than screened stars in our own galaxy. They also pulsate with a shorter period. In this paper, we exploit these new features to constrain chameleon gravity to level three orders of magnitude lower the previous measurements. These constraints are currently the strongest in the literature.

scholarly journals Tests of modified gravity theories in the Solar System

2015 ◽  
Vol 93 (2) ◽  
pp. 151-165
Author(s):  
Ali Mozaffari
Keyword(s):  
Gravitational Field ◽  
Solar System ◽  
Modified Gravity ◽  
Saddle Points ◽  
Modified Newtonian Dynamics ◽  
Newtonian Dynamics ◽  
Modified Gravity Theories ◽  
Different Types ◽  
Theories Of Gravity ◽  
Positive Results

We review the case for testing preferred acceleration scale theories of gravity (sometimes falling under the guise of modified Newtonian dynamics) in the Solar System using the forthcoming LISA Pathfinder (LPF) mission. Using a combination of analytical and numerical results, we suggest that different types of theory should be detectable using the predicted anomalous tidal stresses effects around the saddle points of the Newtonian gravitational field. The saddle point bubbles’ expected extent of ∼400 km are to be contrasted with potential miss parameters of ≤10 km, making such a test in easy reach of LPF. We also consider routes to constraining our theories from data, based on scenarios of both null and positive results.

scholarly journals SIMULATIONS OF SOLAR SYSTEM OBSERVATIONS IN ALTERNATIVE THEORIES OF GRAVITY

2015 ◽  
Author(s):  
A. HEES ◽  
B. LAMINE ◽  
S. REYNAUD ◽  
M.-T. JAEKEL ◽  
C. LE PONCIN-LAFITTE ◽  
...  
Keyword(s):  
Solar System ◽  
Alternative Theories Of Gravity ◽  
Theories Of Gravity ◽  
Alternative Theories

The Origin of the Moon

1962 ◽  
Vol 14 ◽  
pp. 149-155 ◽  
Author(s):  
E. L. Ruskol
Keyword(s):  
Chemical Composition ◽  
Solar System ◽  
The Moon ◽  
The Earth ◽  
The Difference ◽  
Origin Of The Moon

The difference between average densities of the Moon and Earth was interpreted in the preceding report by Professor H. Urey as indicating a difference in their chemical composition. Therefore, Urey assumes the Moon's formation to have taken place far away from the Earth, under conditions differing substantially from the conditions of Earth's formation. In such a case, the Earth should have captured the Moon. As is admitted by Professor Urey himself, such a capture is a very improbable event. In addition, an assumption that the “lunar” dimensions were representative of protoplanetary bodies in the entire solar system encounters great difficulties.

Sign in / Sign up

Export Citation Format

Share Document