(All that follows is from the website: Newton Physics)
The Deflection of Light by the Sun’s Gravitational Field: An Analysis of the 1919 Solar Eclipse Expeditions.
Note: After the publication of [this book], a much more complete study of the observations of the deflection of light and radio waves by the Sun has been published under the title:
This paper can be read direcly on the Web.
INTRODUCTION – According to Einstein’s general theory of relativity published in 1916, light coming from a star far away from the Earth and passing near the Sun will be deviated by the Sun’s gravitational field by an amount that is inversely proportional to the star’s radial distance from the Sun (1.745” at the Sun’s limb). This amount (dubbed the full deflection) is twice the one predicted by Einstein in 1911, using Newton’s gravitational law (half deflection). In order to test which theory is right (if any), an expedition led by Eddington was sent to Sobral and Principe for the eclipse of May 29, 1919 . The purpose was to determine whether or not there is a deflection of light by the Sun’s gravitational field and if there is, which of the two theories mentioned above it follows.
The expedition was claimed to be successful in proving Einstein’s full deflection [1,2]. This test was crucial to the general approval that Einstein’s general theory of relativity enjoys nowadays.
However, this experimental result is obviously not in accordance with the result found in [chapter 10]. This is not a problem, as we will show that the deflection was certainly not measurable. We will see that the effect of the atmospheric turbulence was larger than the full deflection, just like the Airy disk. We will also see how the instruments could not give such a precise measurement and how the stars distribution was not good enough for such a measurement to be convincing. Finally, we will discuss how Eddington’s influence worked for Einstein’s full displacement and against any other possible result.