Cosmological concept · Cosmology
The Cosmological Constant (Λ)
Cosmology & UniverseActive Research
Definition
A constant energy density of empty space, Einstein's Λ, the simplest candidate for dark energy.
Scientific overview
Einstein introduced the cosmological constant in 1917, later calling it his 'greatest blunder'. The 1998 discovery of cosmic acceleration revived it: a constant vacuum energy fits the data and gives the Λ in ΛCDM. Why its value is so tiny compared to particle-physics predictions is one of the deepest problems in physics.
Open questions
- Why is Λ so small (the cosmological-constant problem)?
- Is dark energy really constant?
Rests on
Related scientists
Knowledge connections
- Related toDark Energy
- Depends onDark Energy
- Part of modelThe Lambda-CDM Model
- Developed byAlbert Einstein
- Related toThe Lambda-CDM Model
- Associated withMatter Density (Ωm)
- Associated withDark Energy Density (ΩΛ)
- Associated withZero-Point Energy
- Associated withVacuum Energy
- Associated withThe Cosmological Constant Problem
Sources & references
The primary and reference sources this topic draws on.
- NASANational Aeronautics and Space Administration
Mission data, planetary science, space telescopes, and public-domain imagery.
Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.