The famous physicist known for the uncertainty principle is Werner Heisenberg. He was a key figure in the development of quantum mechanics, a branch of physics that focuses on the behavior of matter and energy at atomic and subatomic levels. Heisenberg introduced the uncertainty principle in 1927, which states that it is impossible to simultaneously know both the exact position and momentum of a particle. This principle has profound implications for our understanding of the nature of reality, suggesting that at quantum levels, behavior can only be predicted statistically rather than deterministically.