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Related to classical physics: quantum physics
Physics that is based on Newton's laws of motion and does not make use of quantum mechanics and the theory of relativity. ♦ Classical mechanics refers to Newton's laws of motion and other principles of mechanics based on them. Classical mechanics does not work when dealing with bodies (such as electrons) moving at speeds close to that of light, or when making measurements of atoms and subatomic particles. These phenomena can only be described by quantum mechanics and the theory of relativity.