invariance

/ ĭn-vâr′ē-əns /

1. The property of remaining unchanged regardless of changes in the conditions of measurement. For example, the area of a surface remains unchanged if the surface is rotated in space; thus the area exhibits rotational invariance. In physics, invariance is related to conservation laws . For example, conservation of angular momentum is directly related to rotational invariance (the laws of physics don't depend on the angle of the reference point), conservation of energy is related to invariance over time (the laws of physics remain the same over time), and conservation of momentum is related to invariance over translations through space (the laws of physics don't depend on the position of the reference point). A form of invariance called Lorenz invariance is fundamental to the theory of Special Relativity. Invariance is also called symmetry.
2. See also Noether's theorem

Example Sentences

This is known as invariance, meaning that objects are perceived to be the same even if they show differences in those less important features.

From Science Daily

As it turns out, this kind of invariance is a key property for matter about to flip from one phase to another.

From Scientific American

The company is saying, “Amidst all this enthusiasm, what fundamental invariance can you bet on?”

From The Verge

Violating these conditions — called charge and parity invariance, C and P for short — would cause matter and antimatter to act differently.

From New York Times

In physics, a symmetry is broadly defined as any kind of invariance under a transformation—in other words, a property of a system that doesn’t get altered when a change is applied to that system.

From Scientific American