classical physics

American  

[klas-ik-uhl fiz-iks] / ˈklæs ɪk əl ˈfɪz ɪks /

noun

1. physics as understood before the advent of quantum mechanics and the theory of relativity, or those aspects of contemporary physics that do not involve or rely on these theories.

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classical physics Scientific  

1. Physics that does not make use of quantum mechanics or the theory of relativity. Newtonian mechanics, thermodynamics, and Maxwell's theory of electromagnetism are all examples of classical physics. Many theories in classical physics break down when applied to extremely small objects such as atoms or to objects moving near the speed of light.

2. ◆ Classical mechanics refers to the classical physics of bodies and forces, especially Newton's laws of motion and the principles of mechanics based on them.

3. Compare quantum mechanics

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Other Word Forms

• classical physicist noun
• classical-physics adjective

Example Sentences

In classical physics, the idea of memory is straightforward.

From Science Daily • Apr. 14, 2026

Unlike classical physics, which predicts precise trajectories for everyday objects such as cricket balls or communications satellites, quantum theory can only predict the likelihood of where a particle might be observed.

From Science Daily • Mar. 10, 2026

She finds as much joy in defying classical physics on the mountain in Aspen as exploring quantum physics in the classroom at Stanford.

From Seattle Times • Jan. 27, 2024

Such states can help scientists fathom how and why the laws of the quantum world transition into the rules of classical physics for larger objects.

From Scientific American • May 12, 2023

Unfortunately for Einstein, the laws of quantum mechanics work incredibly well, and you can’t successfully explain quantum effects with traditional classical physics.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife