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

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

Of particular interest for researchers in the field are the peculiar and bizarre properties of quantum particles -- which deviate completely from the laws of classical physics and can make materials magnetic or superconducting.

From Science Daily • Apr. 10, 2024

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

So at first there was not one Scientific Revolution but two, one exemplified by Newton’s classical physics, the other by Rutherford’s nuclear physics.

From "The Invention of Science" by David Wootton