Re: Weakness in the results of the three tests of GR shown in rhe lasr century,.

Mr. Hertz: Here is a good article you may like on the refraction
explanation of the delay.
"Shapiro Time Delay derivates from Refraction" = by Serret
"7. CONCLUSION
The Shapiro delay decreases logarithmically
as a function of the distance to the Sun. But
the only measurements accessible to the
public are those made according to the
observation days, which does not make it
possible to verify with precision the Shapiro
delay as a function of a distance to the Sun.
And if the relativistic explanation by
deformation of the space-time is generally
accepted, it can be criticized for for its
various equations and it is criticized by some
for its possible variation according to the
wavelength.
We can then advance another explanation:
the solar corona being necessarily surrounded
by gas, this slight presence of gas would be
enough to generate a phenomenon of
refraction. The decay curve would be
logarithmic as well. Far from the Sun, an
exponential decay of the concentration (as for
the Earth's atmosphere) would explain that
most of the measurements are less than 40 μs.
The best way to make sure of this possible
refraction phenomenon is to measure the
Shapiro delay as a function of the distance to
the Sun and especially as a function of
frequency, i.e. with radar waves and with
radio waves."
Also: "The Shapiro Delay: A Frequency Dependent Transit-Time Effect"
Edward H. Dowdye, Jr