vacuum energy

American  

[vak-yoom en-er-jee, vak-yuhm] / ˈvæk yum ˌɛn ər dʒi, ˈvæk yəm /

noun

1. Physics. the energy present in empty space due to quantum fluctuations, associated with the instantaneous appearance and mutual annihilation of particle–antiparticle pairs and thought to be responsible for the accelerating expansion of the universe.

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vacuum energy Scientific  

1. Background energy in a vacuum associated with constant vacuum fluctuations. Some astronomers believe vacuum energy to be the source of energy for the apparent acceleration of the expansion of the universe.

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Other Word Forms

• vacuum-energy adjective

Example Sentences

What matters is that this vacuum energy produces a measurable effect.

From Science Daily • Mar. 10, 2026

In that case, cosmologists will have to explain what suppresses the influence of vacuum energy in the universe.

From Scientific American • Apr. 29, 2023

In 1966, Soviet physicist Erast Gliner showed that Einstein’s equations could also produce objects that to outside observers look and behave exactly like a black hole--yet are, in fact, giant balls of vacuum energy.

From Science Magazine • Feb. 26, 2023

"But it's not empty. Think of it as a kind of vacuum energy permeating the fabric of spacetime that defies measure."

From Los Angeles Times • Mar. 14, 2018

Scientists sometimes also call it vacuum energy or, more exotically, quintessence.

From "A Short History of Nearly Everything" by Bill Bryson