Eddington was one of the premier scientists at the turn of
the century. Here is some more information about this
In relation to relativity teory he wrote a book
The Mathematical theory of Relativity(1923.
Einstein said of the work "the finest presentation of the subject in any language". This book did much to popularise
the theory and to help in it's quick acceptance as cannon.
Dirac took lectures on the subject under Eddington and
soon after formulated the theory of relativistic quantum mechanics. A reporter is reputed to have asked Eddington
"they say you are one of only three men in the world
that understand the theory of relativity". Eddington paused and the reporter said "now Sir Eddington, don't be shy"
to which Eddington replied, "no, I'm just trying to think who the third person is".
Eddington got Chandrasekhar to Cambridge. On his
way to Cambridge Chandra worked out the condition needed to create a black hole. Eddington dismissed the idea out of hand. Eddington's opinion was so powerfull that
no research was done on black holes for about another 40 years, and then by Americans, notable Kip Thorne,
John Wheeler and Misner (sorry don't know his first name). Chandra abandoned his own work, but 60 years later was vindicated
with a Nobel prize.
Eddington introduced the idea of the two tables.
In a lecture he said that before him there were tow table, the table of common sense and the scientific table, both
as real as each other. The scientific table was composed of tiny charges moving at incredible velocities with mostly nothing in between, the table of sense had colour, taste, etc...
Later in life Eddington became crazy. The fine structure constant is the coupling constant of electromagnetisim and has a value of approximatly 1/127. Eddington believed that it had to be exactly 1/127 but his reasons came from numerology applied to the Bible. The quality of his earlier work meant that this late lapse in his thinking has not
tarnished his reputation.
He has a crater on the Moon named after him.