Related papers: The Light-cone Effect on the Shapiro Time Delay
It is shown that the finite speed of gravity affects very-long baseline interferometric observations of quasars during the time of their line-of-sight close angular encounter with Jupiter. The next such event will take place in 2002,…
A v_J/c correction to the Shapiro time delay seems verified by a 2002 Jovian observation by VLBI. In this Essay, this correction is interpreted as an effect of the aberration of light in an optically refractive medium which supplies an…
The time delay of light as it passes by a massive object, first calculated by Shapiro in 1964, is a hallmark of the curvature of space-time. To date, all measurements of the Shapiro time delay have been made over solar-system distance…
Using a relatively simple method, I compute the v/c correction to the gravitational time delay for light passing by a massive object moving with speed v. It turns out that the v/c effects are too small to have been measured in the recent…
Equations of light, propagating from quasar to observer on earth, are integrated in the time-dependent gravitational field of the solar system by making use of either retarded or advanced solutions of the Einstein field equations. This…
The Shapiro effect, also known as the gravitational time delay, is close kin to the gravitational deflection of light that was the central topic of our Summer School. It is also an interesting test bed for exploring a topic that provides…
Fomalont and Kopeikin have recently succeeded in measuring the velocity-dependent component of the Shapiro time delay of light from a quasar passing behind Jupiter. While there is general agreement that this observation tests the…
We study the effects of a finite mass for the photon on its propagation in a weak gravitational field. In particular, we analyse the gravitational time delay, also known as the Shapiro effect. We work in isotropic coordinates in the…
The time delay experienced by a light ray as it passes through a changing gravitational potential by a non-zero mass distribution along the line of sight is usually referred to as Shapiro delay. Shapiro delay has been extensively measured…
A relativistic sub-picosecond model of gravitational time delay in radio astronomical observations is worked out and a new experimental test of general relativity is discussed in which the effect of retardation of gravity associated with…
The time delay of a light signal in the quadrupole field of a body at rest is determined in the second post-Newtonian (2PN) approximation in harmonic coordinates. For grazing light rays at Sun, Jupiter, and Saturn the 2PN quadrupole effect…
The recent passage of Jupiter by the quasar QSO J0842+1835 at a separation of 3.7 arcminutes on September 8, 2002, combined with recent advances in interferometric radio timing, has allowed for the first measurement of higher-order…
The measurement of the Shapiro time delay in binary pulsar systems with highly inclined orbit can be affected both by the motion of the pulsar's companion because of the finite time it takes a photon to cross the binary, and by the…
We have determined the relativistic light deflection of the quasar J0842+1835 as Jupiter passed within 3.7' on 2002 September 8, by measuring the time delay using the VLBA and Effelsberg radio telescopes at 8.4 GHz. At closest approach,…
In this paper, we examine the Shapiro delay caused by the close approach of an asteroid to the LISA constellation. We find that the probability that such an event occurs at a detectable level during the time interval of the mission is…
We study the effect of retardation of gravity in binary pulsars. It appears in pulsar timing formula as a periodic excess time delay to the Shapiro effect. The retardation of gravity effect can be large enough for observation in binary…
To determine whether the Shapiro time delay of light passing near a moving object depends on the ``speed of gravity'' or the ``speed of light,'' one must analyze observations in a bimetric framework in which these two speeds can be…
Dark matter influence globally galactic Keplerian motions and individually, by microlensing, star's acromatic luminosities. Moreover gravity slows down time as probed by gravitational redshift. Therefore pulsar's (PSR's) periods may record,…
Video observations of Jupiter obtained by amateur astronomers over the past eight years have shown five flashes of light of 1-2 s. The first three of these events occurred on 3 June 2010, 20 August 2010, and 10 September 2012. Previous…
We investigate two general relativistic effects - namely, the Shirokov and Shapiro effects - within the framework of the Zipoy-Voorhees spacetime ($q$-metric), which generalizes the Schwarzschild solution by incorporating a quadrupole…