# Definition of *cosmological constant* in English:

## cosmological constant

### Pronunciation /ˌkäzməˈläjəkəl ˈkänstənt/ /ˌkɑzməˈlɑdʒəkəl ˈkɑnstənt/

### noun

Physics

An arbitrary constant in the field equations of general relativity.

*‘Einstein introduced the cosmological constant to his equations of general relativity because he believed the universe was static.’*

*‘On the plus side, the vanishing vacuum energy that is implied by supersymmetry ensures that the cosmological constant vanishes.’**‘We are making fast progress on understanding the implications of the existence of a cosmological constant for quantum gravity.’**‘Quintessence is dynamic, unlike the cosmological constant, and its average energy density and pressure slowly decay with time.’**‘Why is the cosmological constant, which characterizes the energy density of the vacuum, so small?’*