What nationality was the man who determined that light has a finite speed?
Ole Rømer Ole Christensen Rømer (] ; 25 September 1644 – 19 September 1710) was a Danish astronomer who in 1676 made the first quantitative measurements of the speed of light.
John Lighton Synge John Lighton Synge ( ; 23 March 1897 – 30 March 1995) was an Irish mathematician and physicist, whose seven decade career included significant periods in Ireland, Canada, and the USA. He was a prolific author and influential mentor, and is credited with the introduction of a new geometrical approach to the theory of relativity.