Albert Einstein Describes Space and Time

Albert Einstein (1879-1955) is considered by many the greatest astrophysicist and single most significant Person of the 20th Century . He is pictured here in the Swiss Patent Office where he did much of his defining work. Einstein 's many visionary scientific contributions include the equivalence of mass and energy (E=mc^2), how the maximum speed limit of light affects measurements of time and space ( special relativity ), and a more accurate theory of gravity based on simple geometric concepts ( general relativity ). One reason Einstein was awarded the 1921 Nobel Prize in Physics was to make the prize more prestigious.