Correction of Cosmological Expansion to Angular Deflection of Light and Radar Echo Delay

2010 ◽  
Vol 49 (4) ◽  
pp. 870-876
Author(s):  
W. Fang ◽  
H. Qing
Author(s):  
Tiberiu Harko ◽  
Zoltan Kovács ◽  
Francisco S. N. Lobo

In the present paper, we consider the possibility of observationally constraining Hořava gravity at the scale of the Solar System, by considering the classical tests of general relativity (perihelion precession of the planet Mercury, deflection of light by the Sun and the radar echo delay) for the spherically symmetric black hole Kehagias–Sfetsos solution of Hořava–Lifshitz gravity. All these gravitational effects can be fully explained in the framework of the vacuum solution of Hořava gravity. Moreover, the study of the classical general relativistic tests also constrains the free parameter of the solution. From the analysis of the perihelion precession of the planet Mercury, we obtain for the free parameter ω of the Kehagias–Sfetsos solution the constraint ω ≥3.212×10 −26  cm −2 , the deflection of light by the Sun gives ω ≥4.589×10 −26  cm −2 , while the radar echo delay observations can be explained if the value of ω satisfies the constraint ω ≥9.179×10 −26  cm −2 .


2010 ◽  
Vol 69 (17) ◽  
pp. 1517-1527 ◽  
Author(s):  
Ye. N. Belov ◽  
O. A. Voytovich ◽  
T. A. Makulina ◽  
G. A. Rudnev ◽  
G. I. Khlopov ◽  
...  

Universe ◽  
2021 ◽  
Vol 7 (8) ◽  
pp. 263
Author(s):  
Ayan Mitra ◽  
Vasilios Zarikas ◽  
Alfio Bonanno ◽  
Michael Good ◽  
Ertan Güdekli

A recent work proposed that the recent cosmic passage to a cosmic acceleration era is the result of the existence of small anti-gravity sources in each galaxy and clusters of galaxies. In particular, a Swiss-cheese cosmology model, which relativistically integrates the contribution of all these anti-gravity sources on a galactic scale has been constructed assuming the presence of an infrared fixed point for a scale dependent cosmological constant. The derived cosmological expansion provides an explanation for both the fine tuning and the coincidence problem. The present work relaxes the previous assumption on the running of the cosmological constant and allows for a generic scaling around the infrared fixed point. Our analysis reveals that, in order to produce a cosmic evolution consistent with the best ΛCDM model, the IR-running of the cosmological constant is consistent with the presence of an IR-fixed point.


Sign in / Sign up

Export Citation Format

Share Document