Richard Feynman is undoubtedly one of the most genius physicist of 20th century. His colourful character sometimes puts u actually thinking that "Can there actually be such a human being after all on this planet Earth!!"

Quantam theorist.

Richard Feynman is without question one of the greatest physicists -- and in fact one of the greatest scientists -- of the 20th century (and probably the most brilliant American scientist ever). He provided the many of the founding ideas of quantum mechanics (for which he got a Nobel Prize), and is considered the grandfather of nanotechnology due to the lectures and papers he produced on the topic well ahead of anyone else. Feynman also worked on the Manhattan Project in the 40s. He's probably the most captivating, colorful, and interesting scientist in history; check out his outrageous anecdotes in the books _Surely You're Joking, Mr. Feynman!_ and _What Do You Care What Other People Think?_. Check out his research, read his books, and learn what he's done for scientific and rational thought -- you'll wish the scale could go higher than 5.