Final answer:
Albert Einstein spearheaded the method of moving from mathematical theories and hypotheses to observable predictions with his theories of special relativity and general relativity, affecting our understanding of relative motion, including the effects of gravity on space and time.
Step-by-step explanation:
Albert Einstein's Work on Relativity
The method that Albert Einstein used in his work on relativity started with developing mathematical theories and hypotheses which led to predictions about observable phenomena. This process resulted in the creation of two theories of relativity: special relativity and general relativity. Special relativity, published in 1905, deals with observers moving at constant velocity relative to one another. By 1916, Einstein had expanded on these ideas to propose general relativity, which addressed situations involving acceleration and the effects of gravity. General relativity predicts behaviors such as the bending of light by gravity, which was famously confirmed during the solar eclipse of 1919, catapulting Einstein to worldwide fame.