According to old-fashioned Newtonian gravity, starlight would be deflected by only half that amount, 0.86 second, as it passed the sun during an eclipse. And what if Eddington measured twice the Einstein deflection?, Dyson was asked by Edwin Cottingham, one of the astronomers on the expedition. How Eddington and his colleagues played them off against one another sealed the fate of Einstein’s theory. Another Sobral telescope, known as an astrograph, also produced lots of star images, but they were blurred and out of focus, perhaps because heat from the sun had affected the telescope mirror. Both of the remaining plates “point to the full deflection 1”.75 of Einstein’s generalized relativity theory,” Dyson and his colleagues wrote in their official report.

Source: New York Times July 31, 2017 18:56 UTC