uncertainty principle
1) Direct citation: ‘The more precisely the position is determined, the less precisely the momentum is known in this instant, and vice versa. ‘
--Heisenberg, uncertainty paper, 1927
2) implications: This is a succinct statement of the "uncertainty relation" between the position and the momentum (mass times velocity) of a subatomic particle, such as an electron. This relation has profound implications for such fundamental notions as causality and the determination of the future behavior of an atomic particle.
Because of the scientific and philosophical implications of the seemingly harmless sounding uncertainty relations, physicists speak of an uncertainty principle, which is often called more descriptively the "principle of indeterminacy."
3) the way I heard the explanation: a particle is within the orbit in every spot of it s orbit and nowhere at the same time.
Author: WERNER HEISENBERG (1901 - 1976)
