Who's greatest? Einstein or Newton? And what one word covers the field that made them so?

Einstien physics The theory of Relativity

I'm inclined to say Einstein, because he revolutionised our understanding of space and time. His field was cosmology - the study of the large scale structure of the universe. Newton was pretty awesome though, and Einstein built on his theories. String theory has not been validated, to the best of my (limited) knowledge. I think Stephen Hawking is the new Einstein.

Both are great, for both made great and wonderful discoveries that have helped out in the long run. The one word, physics. Both played a hand in making discoveries that we study in physics.

Both are great, but I would have to go with Keplar. His laws of plantary motion were the foundation that Newton built his laws of universal gravitation and laws of motion upon. Without the work of Keplar, it is doubtful that Newton would have had the basis for his work. Einstein's theory of relativity has only held its ground do to the inability to be disproven, not proven. To date it is widely accepted, but so was that thought that the Earth was the center of the universe for centuries. Einstein's work has brought about great advances, but I can not consider him the greatest. My favorite quote of Einstein's: "I often wonder, 'Am I or the rest of the world crazy?' "