uncertainty principle

American  

noun

Physics.

1. the principle of quantum mechanics, formulated by Heisenberg, that the accurate measurement of one of two related, observable quantities, as position and momentum or energy and time, produces uncertainties in the measurement of the other, such that the product of the uncertainties of both quantities is equal to or greater than h/ 2 π, where h equals Planck's constant.

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uncertainty principle British  

noun

1. Also known as: Heisenberg uncertainty principle.   indeterminacy principle.  the principle that energy and time or position and momentum of a quantum mechanical system, cannot both be accurately measured simultaneously. The product of their uncertainties is always greater than or of the order of h , where h is the Planck constant

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uncertainty principle Scientific  

/ ŭn-sûr′tn-tē /

1. A principle, especially as formulated in quantum mechanics, that greater accuracy of measurement for one observable entails less accuracy of measurement for another. For example, it is in principle impossible to measure both the momentum and the position of a particle at the same time with perfect accuracy. Any pair of observables whose operators do not commute have this property. As defined in quantum mechanics, it is also called Heisenberg's uncertainty principle. Similar uncertainty principles hold for non-quantum mechanical systems involving waves as well.

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uncertainty principle Cultural  

1. The statement in quantum mechanics, formulated by Werner Heisenberg, that it is impossible to measure two properties of a quantum object, such as its position and momentum (or energy and time), simultaneously with infinite precision.

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Etymology

Origin of uncertainty principle

First recorded in 1930–35

Example Sentences

Simon Stephens’ drama, presented at the Mark Taper Forum in 2017, is a two-hander that tests the validity of the uncertainty principle in the arena of human relationships.

From Los Angeles Times

To the chagrin of many physicists, the Heisenberg uncertainty principle determines that one cannot simultaneously know a signal's position and momentum, or voltage and current, with accuracy.

From Science Daily

Quantum theory tells us that particles obey Heisenberg's uncertainty principle, and we can never know their position or velocity at the same time.

From Science Daily

This is because of an idea in quantum physics called Heisenberg's uncertainty principle.

From Scientific American

For instance, Einstein refused to believe that Heisenberg's uncertainty principle—which limits how much can be known about a particle's position and speed—was fundamental.

From Scientific American