virtual particle

American  

noun

Physics.

1. an elementary particle of transitory existence that does not appear as a free particle in a particular situation but that can transmit a force from one particle to another.

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virtual particle Scientific  

1. A short-lived subatomic particle whose existence briefly violates the principle of conservation of energy. The uncertainty principle of quantum mechanics allows violations of conservation of energy for short periods, meaning that even a physical system with zero energy can spontaneously produce energetic particles. The more energy a virtual particle has, the shorter its existence. Interactions between normal particles and virtual particles play a crucial role in quantum field theory analyses of interactions between real particles.

2. See also Casimir effect Feynman diagram vacuum fluctuation

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Etymology

Origin of virtual particle

First recorded in 1970–75

Example Sentences

This mind-blowing feature of the quantum world plays a crucial role in particle physics experiments; indeed, the discovery of the Higgs boson was enabled by virtual particle effects at the LHC.

From Scientific American

Last year, a large collaboration co-chaired by El-Khadra brought together several teams of researchers—each specializing in one type of virtual particle—and published a ‘consensus’ value for the fundamental constant.

From Scientific American

Instead they are scanning for the effects of a virtual particle on the isotopes—similar to investigations involving magnetic fields—says Joonseok Hur, a Ph.D. student at M.I.T. and co-lead author of the new ytterbium study.

From Scientific American

In the vacuum, the virtual particle pairs can move more easily along the magnetic field than perpendicular to it, Heyl explains.

From Science Magazine

In all B meson decays, at one point a heavier “virtual” particle is created and then quickly disappears—a strange phenomenon allowed by quantum mechanics.

From Scientific American