About Albert Einstein :
Albert Einstein (born March 14, 1879, Ulm, Württemberg, Germany—died April 18, 1955, Princeton, New Jersey, U.S.), was a German-born theoretical physicist, best known for his Special and General Theory of Relativity and the concept of mass-energy equivalence expressed by the famous equation, E = mc2. He received the Nobel Prize in Physics in 1921 “for his services to theoretical physics, and especially for his discovery of the law of the photoelectric effect” and he made some essential contributions to the early development of quantum theory. He was named "Person of the Century" by Time magazine in 1999, the fourth most admired person of the 20th Century according to a 1999 Gallup poll, and “the greatest scientist of the twentieth century and one of the supreme intellects of all time” according to “The 100: A Ranking of the Most Influential Persons in History” in 1978.
About Stephen Hawking :
Stephen Hawking, (January 8, 1942) the brilliant British theoretical physicist who overcame a debilitating disease to publish wildly popular books probing the mysteries of the universe, died at 76 on March 14, 2018. Considered by many to be the world's greatest living scientist, Hawking was also a cosmologist, astronomer, mathematician and author of numerous books including the landmark "A Brief History of Time," which has sold more than 10 million copies. With fellow physicist Roger Penrose, Hawking merged Einstein's theory of relativity with quantum theory to suggest that space and time would begin with the Big Bang and end in black holes. Hawking also discovered that black holes are not completely black but emit radiation and will likely eventually evaporate and disappear. "I try to lead as normal a life as possible, and not think about my condition, or regret the things it prevents me from doing, which are not that many," he wrote on his website.